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A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Can the temporary use of right ventricular assist devices (RVADs) bridge patients to recovery who suffer acute right ventricular failure after cardiac surgery? More than 183 papers were found using the reported search, of which 13 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Indications for surgical intervention included coronary artery bypass surgery, valve replacement, post-heart transplant and left ventricular assist device insertion. Significant reductions in central venous pressure (P = 0.005) and mean pulmonary artery pressures (P < 0.01) were reported during and after RVAD support. Furthermore, increases in right ventricular cardiac output (P < 0.05), right ventricular ejection fraction (P < 0.05), right ventricular stroke work (P < 0.05) and pulmonary artery oxygen saturations (P < 0.05) were also seen. Assessment by one study showed that on Day 7 after RVAD removal, the right ventricular ejection fraction had increased by up to 40%. Dynamic echocardiography studies performed before, during and after RVAD placement demonstrated that after RVAD implantation, right ventricular end-diastolic dimensions (P < 0.05) and right atrial dimensions decreased (P < 0.05) and right ventricular ejection fraction (P < 0.05) increased. Although several studies successfully weaned patients from an RVAD, there were several complications, including bleeding requiring surgical intervention. However, this may be reduced by using percutaneous implantation (bleeding incidence: 4 of 9 patients) rather than by a surgically implanted RVAD (bleeding incidence: 5 of 5 patients). However, mortality is higher in percutaneous RVAD patients rather than in surgical RVAD (80–44%) patients. Causes of death cited for patients on an RVAD included multiorgan failure, sepsis, thromboembolic events, reoccurring right heart failure and failure to wean due to persistent right ventricular failure. We conclude that RVADs have been successfully used to bridge patients to recovery after cardiac surgery; however, RVADs carry numerous risks and a high mortality rate.

A best evidence topic in cardiovascular surgery was written according to a structured protocol. The question addressed was whether patients with severe asymptomatic carotid and coronary artery diseases should undergo simultaneous carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG). A total of 624 papers were found using the reported search, of which 20 represent the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study results of these papers are tabulated. Previous cohort studies showed mixed results, while advocating for the necessity of a randomized controlled trial (RCT). A recent RCT showed that patients undergoing prophylactic or simultaneous CEA + CABG had lower rates of stroke (0%) compared with delayed CEA 1–3 months after CABG (7.7%), without significant perioperative mortality difference. This study included patients with unilateral severe (>70%) asymptomatic carotid stenosis requiring CABG. An earlier partly randomized trial also showed better outcomes for patients undergoing simultaneous procedures (P = 0.045). Interestingly, systematic reviews previously failed to show compelling evidence supporting prophylactic CEA. This could be partly due to the fact that these reviews collectively analyse different cohort qualities. Neurological studies have, however, shown reduced cognitive and phonetic quality and function in patients with unilateral and bilateral asymptomatic carotid artery stenosis. Twenty-one RCTs comparing lone carotid artery stenting (CAS) and CEA informed the American Heart Association guidelines, which declared CAS comparable with CEA for symptomatic and asymptomatic carotid stenosis (CS). However, the risk of death/stroke for CAS alone is double that for CEA alone in the acute phase following onset of symptoms, while CEA alone is associated with a doubled risk of myocardial infarction. There is, however, no significant difference for combined 30-day risk of death/stroke/myocardial infarction. Outcomes of hybrid or simultaneous CAS/CABG procedures show comparable results, albeit from rather small cohorts. While current evidence leans towards simultaneous CEA/CABG, the emergence of hybrid operating theatres in various institutions may allow larger cohorts with subsequent significant data on simultaneous CAS/CABG. A randomized controlled trial comparing both approaches would be crucial in informing future updates of existing guidelines.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was if thymectomy in non-thymomatous myasthenia gravis was of any benefit? Overall, 137 papers were found using the reported search, of which 16 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The outcome variables were similar in all of the papers, including complete stable remission (CSR), pharmacological remission, age at presentation, gender, duration of symptoms, preoperative classification (Oosterhius, Osserman or myasthenia gravis Foundation of America (MGFA)), thymic pathology, preoperative medications (steroids, immunosuppressants), mortality and morbidity. We conclude that evidence-based reviews have shown that relative rates of thymectomy patients compared with non-thymectomy patients attaining outcome indicate that the former group of patients is more likely to achieve medication-free remission, become asymptomatic and clinically improve (54%, P < 0.01), particularly patients with severe and generalized symptoms (P = 0.007). Patients with generalized myasthenia gravis showed 11% stronger association with favourable outcomes after thymectomy. Some studies show early remission rates (RRs), as early as 6 months post-thymectomy, of 44%. Overall, the reported remission rate for non-thymomatous myasthenia gravis is between 38 and 72% up to 10 years of follow-up. Among these patients, those with thymic hyperplasia show the best complete stable remission rates (42%, P < 0.04) in the majority of studies. Age showed variability across the studies and the cut-off was also different among them. Overall age < 45 years showed a higher probability of achieving complete stable remission during follow-up (81% benefit rate (BR), P < 0.02). Pharmacological improvement is reported between 6 and 42%. However, the certainty of these benefits has not been established due to factors such as the confounding differences between myasthenia gravis patients receiving and not receiving thymectomy, the non-randomized nature of class II studies and the lack of Class I evidence to support its use. There is currently a randomized trial ongoing looking at thymectomy by sternotomy vs controls and the results are eagerly awaited.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: is sternotomy approach superior to a thoracotomy approach for a modified Blalock–Taussig shunt procedure? More than 58 papers were found using the search as described below, of which 11 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Three of seven papers compared the sternotomy and thoracotomy approaches. The operative approach was a significant predictor of shunt failure. The criterion used to define early shunt failure was either the complete occlusion during hospitalization or the need to return to the operating room for a second shunt. The studies that compared the thoracotomy and sternotomy approaches observed increased shunt failure rates in the thoracotomy group. The sternotomy approach was associated with advantages like less pulmonary artery distortion, ease of technical performance, cosmetic advantage of a single sternotomy incision, ease of ligation of patent ductus, less phrenic nerve injury, less collateral formation in chest wall adhesions and less thoracotomy induced scoliosis. However, other papers studied either the sternotomy approach only or the thoracotomy approach and drew conclusions regarding risk factors for operative morbidity and mortality. We conclude that the sternotomy approach is beneficial to neonates and infants undergoing modified Blalock–Taussig shunt when compared with the conventional thoracotomy approach.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: Does repeat thymectomy improve symptoms in patients with refractory myasthenia gravis after thymectomy? A total of 189 papers were found using the reported search, of which seven represented the best evidence to answer the clinical question. The outcome measures included operative mortality and morbidity, as well as long-term remission rate. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All the studies were small (4–21 patients), retrospective, single institutional case series. There was considerable heterogeneity in the studies. The interval between the first and second operation ranged from less than a year to over 10 years. The operative approach of the initial operation included transcervical, trans-sternal and substernal approaches. The maximal medical therapy received by the patients prior to reoperation varied from anticholinesterase alone to cytotoxic therapy and regular plasmapheresis. The severity of symptoms ranged from Osserman Class IIa to V. The operative approach to re-thymectomy included resternotomy, thoracoscopy and a combination of both. There was no perioperative mortality. One study reported injury to the innominate vein at resternotomy in 3 (14.3%) patients. One study reported myasthenic crisis in 2 patients in the postoperative period. Only one study reported complete remission in 2 patients. In general, however, 52–95% of patients reported some improvement. There was no consistent, objective measure of improvement in these studies. We conclude that repeat thymectomy for patients with refractory myasthenia gravis after previous thymectomy is safe especially for patients whose first procedure was transcervical. Complete remissions are rare but, in these small series, 60–70% of patients report improvement. Clinical improvement appears to be associated with the presence of residual thymic tissue at the second operation, but these cannot be reliably identified on preoperative imaging. Patient selection remains driven by symptoms.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was, in adult patients undergoing cardiac surgery requiring extracorporeal cardiopulmonary bypass (CPB), does administration of desmopressin acetate (DDAVP) reduce postoperative blood loss and transfusion requirements? Altogether 38 papers were found using the reported search, of which 19 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Perioperative administration of DDAVP in adult patients undergoing cardiac surgery requiring CPB may result in a small but significant reduction in postoperative blood loss. However, this does not translate into a reproducible, clinically significant reduction in exposure to transfusion in unselected patients exposed to CPB. Several sub-groups of patients have been identified in whom DDAVP reduces postoperative blood loss and transfusion requirements. These sub-groups include patients who have received preoperative aspirin within 7 days of surgery, patients with CPB times in excess of 140 min and patients with demonstrable pre- or perioperative platelet dysfunction as determined by TEG analysis or platelet function assays. Platelet dysfunction at the time of surgery may be secondary to preoperative administration of antiplatelet medications, the result of pathological processes such as von Willebrands disease, uraemia or aortic stenosis with its associated sheer stress, as well as operative variables such as prolonged exposure to CPB. The evidence does not support the routine use of DDAVP in all cardiac surgery; indeed, it is clear that there is no significant reduction in postoperative blood loss or transfusion requirements with the administration of DDAVP in patients undergoing isolated coronary artery bypass grafting (CABG) in the absence of the features noted above. Given the absence of a clinically significant reduction in exposure to blood transfusion in unselected patients, we cannot recommend the routine use of DDAVP in patients exposed to CPB. However, DDAVP may reduce postoperative bleeding in patients who have received preoperative aspirin within 7 days of surgery, patients with CPB times in excess of 140 min and patients with demonstrable platelet dysfunction and should be used selectively in these subgroups.

A best evidence topic was written according to a structured protocol. The question addressed was, should the practising interventional cardiologist use drug-eluting stents (DESs) or bare-metal stents (BMSs) when undertaking primary percutaneous coronary intervention (PCI) in diabetic patients. The relevant outcomes that were used to determine the answer to this question included: in-stent restenosis, target vessel revascularization (TVR), mortality, myocardial infarction and in-stent thrombosis. The OVID Medline database was used to carry out the reported search for abstracts of relevant journal articles. Altogether 102 papers were found, of which 7 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. From the evidence available, we conclude that in-stent restenosis is less likely to occur over a follow-up of at least 6 months if a DES is used instead of a BMS. Furthermore, TVR is less likely to be required in diabetic patients who receive a DES in comparison with a BMS. Nevertheless, no significant difference in mortality between stents was detected by the studies reviewed. This included no difference in the incidence of cardiac and non-cardiac causes of death. There was evidence showing that DESs are associated with a decrease in the risk of myocardial infarction and, in particular, a decrease in non-Q-wave myocardial infarction. However, there was also conflicting evidence demonstrating no significant difference in the incidence of myocardial infarction between diabetic patients who had received a BMS or a DES. Moreover, the available evidence showed no significant difference in the risk of in-stent thrombosis for all DESs with the exception of Sirolimus eluting stents in which the evidence was not consistent. In summary, the available evidence supports the use of DESs over BMSs in diabetic patients undergoing primary PCI.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was that whether patients who are dependent on chronic dialysis have higher morbidity and mortality rates than the general population when undergoing cardiac surgery. These patients often require surgery in view of their heightened risk of cardiac disease. Altogether 278 relevant papers were identified using the below mentioned search, 16 papers represented the best evidence to answer the question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses were tabulated. Dialysis-dependent (DD) patients undergoing coronary artery bypass grafting (CABG) or valve replacement have higher morbidity but acceptable outcomes. There is some evidence to show that outcomes after off-pump coronary artery bypass grafting (OPCAB) are better than after on-pump coronary artery bypass grafting (ONCAB) and that results are worse in DD patients with diabetic nephropathy. Patients undergoing combined procedures have a higher mortality.

A best-evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was, should the practicing interventionalist use manual aspiration systematically in all patients undergoing percutaneous coronary intervention (PCI) or only in selected patients with an angiographically obvious thrombotic burden? Altogether, 198 papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that the evidence demonstrates that clinical and angiographic outcomes with respect to manual thrombectomy are similar and encouraging for patients with both angiographic evidence of thrombus burden and those in whom it is used routinely. In addition, there is no significant increase in major adverse cardiac events when routine use of manual aspiration is adopted as opposed to reserving its use for those patients with angiographic evidence of thrombus. In summary, the evidence supports the use of routine systematic manual aspiration in all patients undergoing primary PCI for ST-elevation myocardial infarction.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether it is safe to divide the left innominate vein (LIV) in aortic arch surgery to improve access. Altogether, 228 relevant papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Following LIV division, the venous drainage takes place via multiple collateral systems such as the azygous/hemiazygous, the internal mammary veins, the lateral thoracic and superficial thoracoabdominal veins, vertebral venous plexus as well as the transverse sinus. The possible complications are mainly left upper limb swelling and neurological symptoms. In one case series of 14 patients, the LIV was divided and ligated to facilitate the exposure for aortic arch surgery. More than 2-year follow-up did not reveal upper limb oedema or neurological symptoms. In two cohorts of 52 patients, the LIV was ligated prior to the superior vena cava (SVC) resection for malignancy. During the mid-term follow-up, no neurological or upper limb symptoms were reported. Although in two studies with 72 and 70 patients undergoing SVC resection it was not specified how many of them had LIV ligation, no relevant complications were reported. In a report, LIV occlusion was observed in 4 patients undergoing left internal jagular vein catheterization for haemodialysis. The reported symptom was left arm swelling with no neurological problems. In a cohort of 18 patients undergoing SVC resection for malignancy and major vein reconstruction, 7 patients underwent ligation of the LIV with no neurological symptoms. It was also concluded that reconstruction of the LIV is not consistent with favourable patency. In a case series of 10 patients with central venous obstruction, collateral pathways to conduct efficient venous drainage were mapped. We conclude that division of the LIV is safe in selected patients and operations. Patients will initially have symptoms of central vein obstruction, but these will decrease with conservative management as collaterals form.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether frailty scoring can be used either separately or combined with conventional risk scores to predict survival and complications. Five hundred and thirty-five papers were found using the reported search, of which nine cohort studies represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. There is a paucity of evidence, as advanced age is a criterion for exclusion in most randomized controlled trials. Conventional models of risk following cardiac surgery are not calibrated to accurately predict the outcomes in the elderly and do not currently include frailty parameters. There is no universally accepted definition for frailty, but it is described as a physiological decline in multiple organ systems, decreasing a patient's capacity to withstand the stresses of surgery and disease. Frailty is manifest clinically as deficits in functional capacity, such as slow ambulation and impairments in the activities of daily living (ADL). Analysis of predictive models using area under receiver operating curves (AUC) suggested only a modest benefit by adding gait speed to a Society of Thoracic Surgeons (STS score)-Predicted Risk of Mortality or Major Morbidity (PROM) risk score (AUC 0.04 mean difference). However, a specialist frailty assessment tool named FORECAST was found to be superior at predicting adverse outcomes at 1 year compared with either EuroSCORE or STS score (AUC 0.09 mean difference). However, risk models incorporating frailty parameters require further validation and have not been widely adopted. Routine collection of objective frailty measures such as 5-metre walk time and ADL assessment will help to provide data to develop new risk-assessment models to facilitate risk stratification and clinical decision-making in elderly patients. Based on the best evidence currently available, we conclude that frailty is an independent predictor of adverse outcome following cardiac surgery or transcatheter aortic valve implantation, increasing the risk of mortality 2- to 4-fold compared with non-frail patients.

A best evidence topic was written according to a structured protocol. The question addressed was whether dissection of the pulmonary ligament during an upper lobectomy would result in improved outcomes. A total of 85 articles were found using the reported search, of which eight represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were complications associated with dissection (atelectasis, bronchial stenosis, bronchial obstruction and bronchial deformation) and preservation (insufficient lung expansion, pooling of effusion and atelectasis) of the pulmonary ligament, ratio (%) of dead space in longitudinal axis (movement of nonoperated lobes), change in the angle (degrees) of main bronchus on the operated side, overall morbidity and mortality, overall survival and conversion rates. In a randomized control trial, the dissection of the pulmonary ligament revealed no significant difference in the dead space ratio or change in the angle of the main bronchus when compared with preservation. Dissection of the ligament, in theory, reduces the free space in the upper thorax by increasing the mobility of the residual lobes. Dissection of the ligament may lead to bronchial deformation, stenosis, obstruction or lobar torsion. Preservation of the ligament may prevent this complication by suppressing the upward movement of residual lobes. However, this may result in pleural effusion in the free thoracic space that may potentially become infected resulting in an empyema or bronchial fistula. Five large case series were analysed; three routinely dissected the pulmonary ligament and two did not. There was no observed difference in clinical outcomes between the two groups. There is no convincing evidence that dissection of the pulmonary ligament in an upper lobectomy significantly improves outcomes and reduces complications.

A best evidence topic was constructed according to a structured protocol. The following question was addressed: of the following two procedures, heart–lung transplantation or bilateral-lung transplantation (BLTx), which offers the best outcome for patients with pulmonary hypertension (PH) listed for thoracic transplantation? Of the 77 papers found using a report search for PH and thoracic transplantation, 9 represented the best evidence to answer this clinical question. Overall, 1189 (67%) lung transplantations and 578 (33%) heart–lung transplantations have been reported worldwide for idiopathic PH. For patients with Eisenmenger's syndrome, HLTx represents up to 70% of the transplantation procedures they undergo. On the whole, neither procedure demonstrated an overall survival benefit, when compared with the other. However, PH patients represent a heterogeneous population according to (i) the primary mechanism of PH and (ii) the consequences of PH on right or/and left heart function. With regard to the latter consideration, the current evidence shows that HLTx offers excellent functional and survival outcomes for patients with congenital heart disease and Eisenmenger's syndrome, severe right or/and left heart dysfunction, and who are chronically inotropic dependent. As far as heart dysfunction is concerned, the published evidence approximated cut-off values at 10–25% for the right ventricle ejection fraction (RVEF) and at 32–55% for the left ventricle ejection fraction (LVEF). In the case of lower values for RVEF and LVEF, HLTx should be performed. In all other patients with PH, the evidence demonstrated that BLTx offers a comparable outcome with the advantage of better organ sharing for other recipients. In order to reduce the waiting time on transplantation lists, cardiac repair and BLTx can be offered in experienced centres to patients with simple cardiac anomalies such as atrial septal defect, patent ductus arteriosus or perimembranous ventricular septal defect.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was ‘Does a minimally invasive approach result in better pulmonary function postoperatively when compared with median sternotomy for coronary artery bypass graft?’. Procedures such as limited sternotomy and minimally invasive direct coronary artery bypass (MIDCAB) though a minithoracotomy were regarded as minimally invasive. Overall, 681 papers were found, of which eight represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, evidence level, relevant outcomes and results of these papers were tabulated. Three randomized, controlled trials (RCT) were included: One study suggested that ministernotomy dividing the corpus sterni (n = 50) offers no advantage over standard sternotomy (n = 50) during the first 10 postoperative days. Two further studies reported on minithoracotomy: one trial presented data suggesting that minithoracotomy (n = 21) is as safe as standard sternotomy with (n = 18) or without (n = 19) cardiopulmonary bypass, but without the benefit ascribed to the minimally invasive incision. A two-centre report investigated pulmonary function as a secondary outcome and claimed that minithoracotomy worsens FEV1 and FVC. The study was not powered to detect these differences as pulmonary function data were available only for one of the centres. Five non-randomized reports were also included in this analysis: These investigated outcomes after minithoracotomy or limited sternotomy compared with standard sternotomy. Patient groups were small, involving

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was ‘is a minimally invasive approach for resection of benign cardiac masses superior to standard full sternotomy?’ A total of 50 papers were found using the reported search, of which, 11 represented the best evidence to answer the clinical question. The authors, country, journal, date of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All 11 papers were retrospective studies, from which 4 were case–control studies comparing the minimally invasive approach with conventional full sternotomy, and 7 were case series. There were two minimally invasive techniques used, a right mini-thoracotomy and a partial hemi-sternotomy, the former being the most commonly used. The resection of benign cardiac masses is a low-risk procedure, with no mortality or conversions to full sternotomy reported. From the 4 case–control studies, cross-clamp time was similar in both groups, and only one report found a prolonged perfusion time with the minimally invasive approach. The incidence of major postoperative complications, including bleeding requiring reoperation (average from case–control studies: 0–4.5 vs 0–5.8%), renal failure (0 vs 0–10%) and prolonged ventilation (6–13 vs 11–19%), for the two approaches was similar. The incidence of postoperative stroke was better for the minimally invasive approach in one study (0 vs 14%, P = 0.023). The main advantages of this technique are shorter intensive care unit (26–31 vs 46–60 h) and hospital stay (3.6–5.2 vs 6.2–7.4 days), the minimally invasive approach being significantly better in one and three reports, respectively. We conclude that minimally invasive resection of a benign cardiac mass using a right mini-thoracotomy approach can be performed with an operative morbidity and mortality at least similar to the standard full sternotomy approach. The information currently available for the minimally invasive approach for the resection of benign cardiac masses is limited and based only on retrospective studies and, therefore, prospective studies are required to confirm the potential benefits of minimally invasive surgery.

A best evidence topic in thoracic surgery was written according to a structured protocol. This was with the purpose of assisting our management of patients with localized malignant mesothelioma of the pleura (LMM). Although the terminology is used inconsistently, this variant has been formally defined by the WHO as a distinct entity defined as localized disease histologically identical to the diffuse form but without any evidence of pleural spread. Treatments for LMM include different combinations of surgery, chemotherapy and radiotherapy. There is an impression that LMM may have a better outcome than the commoner diffuse form of malignant mesothelioma that has been reported to have a survival between 8 and 14 months. In order to advise our patients on prognosis, we studied the duration of survival after surgical resection of LMM. A total of 150 papers were found, of which 16 represented the best evidence to answer the question. The authors, journal, date, country of publication, study type, relevant outcomes and results of these papers are tabulated. It is difficult to combine the results of these 16 papers because both treatments and results are reported differently. Some report median survival (range: 11.6–36 months) and others disease-free survival (range: 0 months to 11 years). Median survival to the longest follow-up was 29 months when calculated by pooling data from informative papers using the Kaplan–Meier method. Our review suggests that survival in LMM is longer than that generally quoted for the more common diffuse form of malignant mesothelioma. Hence, aggressive treatment of LMM may be reasonable in appropriate patients.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: in patients with non-small-cell lung cancer that is found to be unresectable at thoracotomy, is incomplete resection superior for achieving survival advantage? Altogether more than 400 papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. In total, data from an estimated 1083 patients were analysed. Three-year survival rates varied from 0 to 22% in incomplete resection and from 0 to 10% in exploratory thoracotomy. Median survival ranged from 6.5 to 19.1 months in incomplete resection and from 5.3 to 17 months in exploratory thoracotomy. The majority of studies (8/9) found survival in incomplete resection to be superior. However, only 3/9 studies presented statistical analysis of results. The largest of these found superior postoperative survival in incomplete resection (including residual nodal disease), one study showed a significant survival difference for R1 but not R2 resection and another with small patient numbers (n = 29) found no significant difference. We conclude that the best evidence suggests that there may be a survival advantage from incomplete resection of non-small-cell lung cancer when there is microscopic (R1) or nodal residual disease, but not when macroscopic residual (R2) disease remains.

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether there is any role for resuscitative emergency department thoracotomy in severe blunt trauma. Emergency thoracotomy is an accepted intervention for patients with penetrating cardiothoracic trauma. However, its role in blunt trauma has been challenged and has been a subject of considerable debate. Altogether, 186 relevant papers were identified, of which 14 represented the best evidence to answer the question. The author, journal, date, country of publication and relevant outcomes are tabulated. The 14 studies comprised 2 systematic reviews and 12 retrospective studies. The systematic review performed by the Trauma Committee of the American College of Surgeons included 42 studies and a cumulative total of 2193 blunt trauma patients who underwent an emergency department thoracotomy, reporting a survival rate of 1.6%. According to this review, 15% of the survivors suffered from neurological sequelae, but survivors from both penetrating and blunt trauma were included. A systematic review comprising 24 studies reported a survival rate of 1.4% among 1047 blunt trauma patients. Of the retrospective studies, 11 report poor survival rates, ranging from 0 to 6%. Only one study reports a higher survival rate (12.2%). Five of the studies reported on the neurological outcome of survivors. The majority of the studies suffered from limitations due to the small number of included cases. The reported survival after an emergency department thoracotomy for blunt trauma is very low in the vast majority of available studies. Furthermore, the neurological sequelae in the few survivors are frequent and severe. Interestingly, some author groups recommend that emergency department thoracotomy should be contraindicated in cases of blunt trauma with no signs of life at the scene of trauma or on arrival at the emergency department. Larger, well-designed series will be required to reach a consensus on valid prognostic factors and specific subgroups of blunt trauma patients with substantial chances of survival.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: ‘Is porcine or bovine valve better for aortic valve replacement?’ Altogether, 562 papers were found using the reported search, of which 15 represented the best evidence to answer the question. All papers represent either level 1 or 2 evidence. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. This best evidence paper includes 9880 patients from 1974–2006 to compare both valve types. All studies compared either all or some of the following outcomes: complication, durability, mortality, functional status and haemodynamic function. Ten of 15 papers assessed the complication profile due to aortic valve replacement in both valve types. Four papers concluded that bovine valves are superior, whereas only one favoured porcine valves. Five papers showed a similar complication profile between both valves. Six of 15 papers commented on valve durability. Both porcine and bovine valve groups have two papers each to support their superiority in valve durability. Two papers demonstrated similar durability in both valves. There are 11 papers comparing the postoperative mortality. We suggest that there is no difference in mortality profile as eight papers showed that both valves had similar mortality profiles. Two papers supported bovine valve and one paper supported porcine valve in this aspect. There were four papers assessing the postoperative functional status, with three papers suggesting that both valve types had similar clinical improvement postoperatively. Eleven papers compared the haemodynamic function. Nine papers were in favour of bovine valves. Two papers demonstrated similar haemodynamic profiles in both valves. In conclusion, the bovine valve is superior in its complication and haemodynamic profiles. Both bovine and porcine valves have comparable results with regard to the mortality, postoperative functional status and valve durability. Significant variability between the valve manufacturers, study designs, study period and patient population in the above studies impose limitations to the comparison of both valves.

A best evidence topic was written according to a structured protocol. The question addressed was what is the optimum prophylaxis against gastrointestinal haemorrhage for patients undergoing adult cardiac surgery: histamine receptor antagonists (H(2)RA) or proton-pump inhibitors? A total of 201 papers were found; of which, 8 represented the best evidence. The authors, date, journal, study type, population, main outcome measures and results were tabulated. Only one randomized controlled trial (RCT) with relevant clinical outcomes was identified. The rest of the studies consisted of five prospective studies and two retrospective studies. In the RCT, there were no reported cases of gastrointestinal haemorrhage in the proton-pump inhibitor cohort, whereas 4 patients taking H(2)RA developed it. The rate of active gastrointestinal ulceration was higher in the H(2)RA cohort in comparison with the proton-pump inhibitor cohort (21.4 vs 4.3%). A prospective study followed 2285 consecutive patients undergoing cardiac surgery who received either no prophylaxis, or a proton-pump inhibitor. Chi-squared analysis showed the risk of bleeding to be lower in those receiving the proton-pump inhibitor (P < 0.05). Another study of 6316 patients undergoing coronary artery bypass grafting demonstrated a reduced risk of gastrointestinal bleed with prophylactic intravenous omeprazole (odds ratio = 0.2; confidence intervals = 0.1-0.8; P < 0.05). One study successfully showed that proton-pump inhibitors are effective in adequately suppressing gastric acid levels, regardless of Helicobacter pylori infection status; conversely, this study suggested that H(2)RAs were not. The evidence for H(2)RAs is marginal, with no study showing a clear benefit. One study showed that ulcer prophylaxis with H(2)RA did not correlate with the clinical outcome. Another study demonstrated gastric ulceration to be a common gastrointestinal complication in spite of regular H(2)RA use. There is also evidence to suggest that acid suppression increases the risk of nosocomial pneumonia, although open heart surgery may be a confounding factor in this association. Two RCTs showed that H(2)RAs may augment the immune system and reducing stress following cardiac surgery. Proton-pump inhibitors appear to be the superior agent for prophylaxis against gastrointestinal bleed in patients undergoing cardiac surgery, although rigorous comparative data are sparse. Furthermore, level-I evidence would confirm this.

A best evidence topic was written according to a structured protocol, asking 'does surgery improve prognosis in patients with small-cell lung carcinoma (SCLC)?' One hundred and thirteen papers were identified, of which the nine papers best able to answer the question were selected and the details of each tabulated. The prohibitive attitude of clinicians toward surgery in SCLC has prevailed since the 1960s, informed by a prospective randomized trial in which 144 patients were assigned to surgical treatment or to radical radiotherapy. Surgery conferred no survival benefit when compared with radical radiotherapy as assessed at 6 monthly intervals up to 10 years post-treatment. Patients with metastatic disease were excluded; however, diagnostic advances subsequent to these trials justify a re-evaluation of the issue, given the greater degree of accuracy with which sub-groups of patients who might benefit from surgery can now be defined. Only one further prospective, randomized trial features in the literature. This study also discerned that no survival benefit was accrued by adding surgery to chemotherapy. However, this study only included patients who responded to an initial course of chemotherapy and also excluded patients with peripheral nodules only. Subsequent investigators have asserted the value of surgery in SCLC. A retrospective case-control study found that surgery significantly improved median survival in patients with stage I disease when compared with patients undergoing medical therapy. One British centre reported survival rates of 52% at 5 years amongst patients undergoing resection and nodal dissection for stage II-IIIA disease. In a retrospective analysis of the Norwegian cancer database, 5-year survival for patients with stage I undergoing surgery was 44.9%, as opposed to 11.3% amongst those treated medically. This finding was echoed in the analysis of the surveillance epidemiology and end results database in the USA, which found improved median survival amongst patients undergoing surgery for limited SCLC. Prospective studies of carefully selected patients have documented good median survival in patients whose tumour was completely resected. We conclude that surgery for early-stage SCLC improves prognosis as part of a multi-modality approach. This echoes the advice of the 2011 national institute of health and clinical excellence guidelines regarding surgery in SCLC.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether endobronchial valves improve outcomes in patients with severe emphysema. Eighty-seven papers were found using the reported search, of which seven represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Endobronchial Valve for Emphysema Palliation Trial demonstrated that endobronchial valve increased forced expiratory volume in one second by 4.3% (95% confidence interval 1.4–7.2) and decreased by 2.5% in the control group (95% confidence interval −5.4 to 0.4) at a 6-month interval. This benefit is more marked in patients who do not have collateral ventilation into the area of lung being isolated as mapped by bronchoscopic physiological mapping (Chartis) or by computed tomography imaging documenting intact fissures. This evidence is reflected in the Endobronchial Valve for Emphysema Palliation Trial. Patients treated with endobronchial valve with high heterogeneity and complete fissures had greater improvement in forced expiratory volume in one second at 6- and 12-month intervals. We conclude that endobronchial valve placement improves lung function, exercise capacity and quality of life in selected patients with emphysematous diseases.

A best evidence topic was written according to a structured protocol. The question addressed was whether smoking cessation prior to cardiac surgery would result in a greater freedom from postoperative complications. A total of 564 papers were found using the reported searches, of which five represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were operative mortality, pulmonary complications, infective complications, neurological complications, transfusion requirements, duration of ventilation, intensive care unit and hospital stay, intensive care unit re-admission, postoperative gas exchange parameters and postoperative pulmonary function. The largest of the best evidence studies demonstrated a significant reduction in pulmonary complications in non-smokers (P

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: 'Is storage of saphenous vein grafts in autologous whole blood prior to coronary artery bypass grafting (CABG) more effective than storage in saline in preserving graft function?' Altogether more than 580 papers were found using the reported search, of which, 10 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Preservation of the vein graft endothelium during graft preparation is of well-recognized importance in forestalling graft occlusion and saphenous vein graft disease following CABG, however, the different preservation capabilities of saline vs autologous whole blood are not well validated. Although there is a complete lack of randomized clinical trials addressing this issue, some studies using basic in vitro techniques and animal models can be extrapolated to answer the clinical question in hand. All are consistent in demonstrating the detrimental effects of saline on vascular endothelium and therefore graft patency, but there is some disagreement in the literature as to whether autologous whole blood is superior as a storage medium. Though three well-designed studies suggest preserved endothelial function when saphenous vein grafts are stored in saline compared with storage in autologous whole blood, data from other studies are unimpressive, with two studies showing no difference. Furthermore, two elegant experiments that seek to mimic in vivo conditions by comparing outcomes postarterialization show no benefit of prior storage in autologous whole blood, despite the initial better-preserved endothelium. Instead, some notice should be taken of alternative storage solutions such as the University of Wisconsin solution, as some early studies suggest that it may be advantageous over both blood and crystalloid solution.

This best evidence topic in Cardiac Surgery was written according to a structured protocol. The question addressed was: for [Jehovah's Witness patients with end-stage heart failure] can these patients undergo a [heart transplantation] without an increased rate of mortality. Altogether, 133 papers were found using the reported search strategy. Of those, 29 papers represented the best evidence to answer the clinical question. Five papers focusing on patients of the Jehovah's Witness (JW) faith who had end-stage heart failure were published. Successful heart transplantation was performed in a total of seven patients without mortality, re-exploration or blood transfusion. One patient had left ventricular reduction surgery twice and another patient had bypass surgery several years after transplantation. Other successful organ transplantations were also reported, including lung, liver, kidney and pancreas in both adult and paediatric patients of the JW faith, with comparable mortality and morbidity to non-JW patients. A publication bias is likely; nevertheless, we conclude that although there are no large studies directly focused on heart transplantation in JW patients, a multidisciplinary team approach to such surgery can make it technically feasible and without an increased mortality risk in suitable candidates. Therefore, such patients may be considered for heart transplantation under selected and favourable circumstances.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Is it worth packing the head with ice in patients undergoing deep hypothermic circulatory arrest (DHCA)? Altogether more than 34 papers were found using the reported search, of which 7 represented the best evidence to answer the clinical question, 5 of which were animal studies, 1 was a theoretical laboratory study and 1 study looked at the ability to cool using circulating water ‘jackets’ in humans. There were no available human studies looking at the neurological outcome with or without topical head cooling with ice without further adjunct methods of cerebral protection. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Four papers studied animals undergoing DHCA for 45 min–2 h depending on the study design, with or without packing the head with ice. The studies all demonstrated improved cerebral cooling when the head was packed with ice during DHCA. They also illustrated an improved neurological outcome, with better behavioural scores (P

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was 'Does surgical debulking for advanced stages of thymoma improve survival?' Altogether, only 17 papers were found using the reported search, of which only 10 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated; these studies have mainly reported the survival and recurrence rates after total vs subtotal resection of thymic tumours in patients receiving or not receiving adjuvant chemoradiotherapy. These studies confirmed that complete resection is the best prognostic factor in thymomas. With regard to subtotal tumour resection/debulking, we did not find any randomized controlled trials. The evidence on this topic is scarce and these 10 reported were retrospective reviews of the operative, histology and survival data of patients with thymoma who had subtotal vs partial resection for advanced stages of thymoma. Although debulking surgery for thymoma had positively affected survival, in six studies, the difference failed to reach statistical significance. Three of the studies, on the other hand, showed a higher survival rate in thymomas in which maximum debulking was performed and the treatment was followed by high-dose irradiation. None of these studies showed any benefit in debulking surgery for thymic carcinoma. Besides histology and tumour cell-type, other factors influencing survival included the tumour stage and the presence of symptoms such as myasthenia gravis as a warning sign at an early stage. Current evidence in the literature on the survival after debulking surgery for thymoma is contradictory, and most of the studies do not show any survival benefit after debulking for thymoma. However, debulking surgery minimizes the tumour size and area for irradiation postoperatively, hence it can result in less damage to the adjacent tissue during radiotherapy and may be considered for patients in advanced stages of thymoma in whom extensive radiotherapy will be required. In these cases, however, the risks of surgery followed by radiotherapy or radiotherapy alone should carefully be assessed prior to the initiation of treatment.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was as follows: In adults with unilateral diaphragmatic paralysis, does diaphragmatic plication offer functional improvement in dyspnoea, better pulmonary function tests (PFTs) and return to activity? A total of 126 papers were found using the reported search, of which 13 represented the best evidence to answer the clinical question. The authors, date and country of publication, patient group studied, surgical approach, study type, relevant outcomes and results of these articles are tabulated. Those articles reporting improvement in PFTs following plication, documented this benefit in the following parameters: mean forced vital capacity (range 17–40%), forced expiratory volume at 1 sec (range 21–27%), functional residual capacity (range 20–21%) and total lung capacity (range 16–19%). The percentage of postoperative improvement in shortness of breath as measured by a dyspnoea score was reported to be between 90 and 96% in the thoracotomy group and 100% in the Video Assisted Thoracoscopic Surgery (VATS) group, the dyspnoea score that was used in all the studies was a visual analogue scale between 0 and 10 where 0 is no dyspnoea and 10 is the worst dyspnoea a patient can have. One of the studies reported postoperative normalization in ventilation perfusion scan (VQ) scan parameters when compared with the preoperative mismatch. Complication rate was similar between the two groups, while the mortality rate was 4% in the thoracotomy group and 0% in the VATS group. The total number of patients included in all the studies combined was 161. All reports included in this review are observational studies (one cohort study and the remainder being case series); therefore, the risk of selection, information and publication biases are high and conclusions should be implemented with caution. We conclude that diaphragmatic plication can improve the functional status, shortness of breath and PFTs of patients with unilateral diaphragm paralysis. Patients undergoing a VATS approach appear to have more advantages in objective and subjective measures (including PFTs, dyspnoea score, length of hospital stay and postoperative complications). Further research with high-quality study designs is advised, focussing mainly on the long-term benefits and assessment of health-related quality of life.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether a conservative fluid management strategy in the perioperative management of lung resection patients is associated with a reduced incidence of postoperative acute lung injury (PALI) and/or acute respiratory distress syndrome (ARDS) in the recovery period. Sixty-seven papers were found using the reported search, of which 13 level III and 1 level IV evidence studies represented the best evidence to answer the question. Two retrospective case-control studies demonstrated a direct association between liberal fluid intake and the incidence of PALI/ARDS following lung resection on multivariate analysis (MVA) with odds ratios (ORs) of 1.42 (95% CI 1.09–4.32, P = 0.011) and 2.91 (1.9–7.4, P = 0.001). In non-PALI/ARDS cases, the mean intraoperative fluid infusion volume was significantly less [1.22 l (1.17–1.26) vs 1.68 l (1.46–1.9) P = 0.005], the fluid balance over the first 24 postoperative hours was significantly less [1.52 l positive (1.44–1.60) vs 2.0 l positive (1.6–2.4) P = 0.026] and cumulated intra- and postoperative fluid infusion was significantly less [2.0 ml/kg/h (1.7–2.3) vs 2.6 ml/kg/h (2.3–2.9) P = 0.003]. These data show that the difference between fluid regimes associated with an increased incidence of PALI/ARDS (i.e. ‘liberal’) and those which are not (i.e. ‘conservative’) is narrow but significant. However, this does not prove a causative role for liberal fluid in the multifactorial development of PALI/ARDS. On this best evidence, we recommend intra- and postoperative maintenance fluid to be administered at 1–2 ml/kg/h and that a positive fluid balance of 1.5 l should not be exceeded in the perioperative period with caution being exercised with regard to the adequacy of oxygen delivery. If the fluid balance exceeds this threshold, a high index of suspicion for PALI/ARDS should be adopted and escalation of the level of care should be considered. If a patient develops signs of hypoperfusion after these thresholds are exceeded, inotropic/vasopressor support should be considered.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'is radiofrequency ablation more effective than stereotactic ablative radiotherapy in patients with early stage medically inoperable non-small cell lung cancer?' Altogether, over 219 papers were found, of which 16 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Radiofrequency ablation (RFA) and stereotactic ablative radiotherapy (SABR) offer a clear survival benefit compared with conventional radiotherapy in the treatment of early stage non-small cell lung cancer (NSCLC) in medically inoperable patients. Overall survival at 1 year (68.2-95% vs. 81-85.7%) and 3 years (36-87.5% vs. 42.7-56%) was similar between patients treated with RFA and SABR. However, 5-year survival was higher in SABR (47%) than RFA (20.1-27%). Local progression rates were lower in patients treated with SABR (3.5-14.5% vs. 23.7-43%). Both treatments were associated with complications. Pneumothorax (19.1-63%) was the most common complication following RFA. Fatigue (31-32.6%), pneumonitis (2.1-12.5%) and chest wall pain (3.1-12%) were common following SABR. Although tumours ≤ 5 cm in size can be effectively treated with RFA, results are better for tumours ≤ 3 cm. One study documented increased recurrence rates with larger tumours and advanced disease stage following RFA. Another study found increasing age, tumour size, previous systemic chemotherapy, previous external beam radiotherapy and emphysema increased the risk of toxicity following SABR and suggested that risk factors should be used to stratify patients. RFA can be performed in one session, whereas SABR is more effective if larger doses of radiation are given over two to three fractions. RFA is not recommended for centrally based tumours. Patients with small apical tumours, posteriorly positioned tumours, peripheral tumours and tumours close to the scapula where it may be difficult to position an active electrode are more optimally treated with SABR. Treatment for early stage inoperable NSCLC should be tailored to individual patients, and under certain circumstances, a combined approach may be beneficial.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'In patients undergoing video-assisted thoracoscopic surgery (VATS) excision, what is the best way to locate a subcentimetre solitary pulmonary nodule (PN) in order to achieve successful excision?' Altogether, 107 papers were found using the reported search, of which 19 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. The hook-wire technique showed a varied success rate ranging from 58 to 97.6% and a relatively higher failure rate due to wire dislodgement. The most common complication of this method was pneumothorax. CT-guided spiral-wire localization displayed a success rate of 86% with the added advantage of providing more stability than the hook-wire technique and permitting manipulation. Radio-guided localization techniques and fluoroscopic-aided methods using contrast media displayed consistently high sensitivities with few complications. The radio-guided technique had the benefit of allowing a longer time-period between the staining of the nodule and the operation. Ultrasonography showed sensitivities ranging from 92.6 to 100%; however, it is highly operator-dependent. Finger palpation was shown to achieve suboptimal results and should be avoided. We concluded that radio-guided surgery is a preferable method. It showed high accuracy with minimal complications and operator dependence in detecting subcentimetre PNs when compared with other techniques such as ultrasonography, finger palpation, fluoroscopic, hook-wire, spiral-wire and microcoil localization.

We addressed the question of whether or not the currently available evidence base supports heparinization in the context of a patient requiring cardiovascular support with an intra-aortic balloon pump (IABP). A best evidence topic was written according to a previously defined structured protocol. A literature search returned 443 papers, 3 of which were deemed relevant. Jiang et al. randomized 153 patients requiring IABP to heparin or no heparin, matched for age, sex and comorbidities. There was no significant difference in limb ischaemia; however, incidence of bleeding was significantly increased in the heparinized group (14.1 vs 2.4%). One cohort study compared two management strategies of IABP in which patients either received heparin universally or selectively with heparin only given for certain pre-defined indications. They reported increased bleeding with universal heparinization (39.2 vs 31.8%) but similar other complication rates. Another cohort study in which patients with IABP were initially treated with glycoprotein IIb/IIIa antagonists only, reported bleeding and ischaemia rates within accepted ranges for heparinized patients. The use of anticoagulation with IABP is intended to reduce the risk of thrombus, thromboembolus or limb ischaemia whilst generating an increased risk of bleeding as a side-effect. The aforementioned studies demonstrate that omitting or implementing a selective use strategy of heparinization during IABP counterpulsation can significantly decrease the incidence of bleeding without an increase in ischaemic events. One study also performed angiography prior to IABP insertion on some of their patients, selecting the less diseased side to insert the IABP. Current evidence on this topic is sparse, especially as relates to patients in the context of cardiothoracic surgery. Just one study specifically looked at surgical patients. However, the existing data suggest that it is safe to omit heparinization when using IABP counterpulsation. The decision to heparinize should be weighed in the context of other indications or contraindications rather than being an automatic response to the use of IABP.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether tricuspid valve (TV) repair with an annuloplasty ring leads to an improved outcome over a conventional suture annuloplasty for patients with severe tricuspid incompetence. Altogether, 306 papers were found using the reported search, of which 14 presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. We found seven studies supporting the use of ring annuloplasty over De Vega's suture annuloplasty. Five studies found no significant difference in outcome between the two techniques. We found only two studies supporting the use of De Vega's suture annuloplasty over ring annuloplasty. Therefore, most of the tabulated studies show good evidence in support of ring annuloplasty compared with De Vega's suture repair for treatment of moderate to severe TV regurgitation. One cohort study identified a 20.4% postoperative failure rate for tricuspid regurgitation (TR) repair and concluded non-application of ring as a predictor for reoperation. One cohort study with a mean follow-up of 17 months reported success rates as high as 97% with ring annuloplasty for TV regurgitation. One large cohort study of 2277 patients with TR who had undergone repair reported a sustained reduction in TR and the rate of recurrence in a 5-year echocardiographic follow-up. One cohort study of 129 patients concluded that ring annuloplasty has the lowest rate of recurrence compared with De Vega's suture repair. An old randomized controlled trial (RCT) on the subject also reported a similar result to the mentioned studies. In contrast, we reviewed one recent study and four older studies and found no significant difference between the two techniques. We reviewed one study that reported De Vega's suture repair as a superior technique to ring annuloplasty. We conclude that there is good evidence supporting ring annuloplasty over conventional De Vega's suture annuloplasty.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether the use of warm or cold blood cardioplegia has superior myocardial protection. More than 192 papers were found using the reported search, of which 20 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. A good breadth of high-level evidence addressing this clinical dilemma is available, including a recent meta-analysis and multiple large randomized clinical trials. Yet despite this level of evidence, no clear significant clinical benefit has been demonstrated by warm or cold blood cardioplegia. This suggests that neither method is significantly superior and that both provide similar efficacy of myocardial protection. The meta-analysis, including 41 randomized control trials (5879 patients in total), concluded that although a lower cardiac enzyme release and improved postoperative cardiac index was demonstrated in the warm cardioplegia group, this benefit was not reflected in clinical outcomes, which were similar in both groups. This theme of benefit in biochemical markers, physiological metrics and non-fatal postoperative events in the warm cardioplegia group ran throughout the literature, in particular the ‘Warm Heart investigators’ who conducted a randomized trial of 1732 patients, demonstrated a reduction in postoperative low output syndrome (6.1 versus 9.3%, P = 0.01) in the warm cardioplegia group, but no significant drop in 30-day all-cause mortality (1.4 versus 2.5%, P = 0.12). However, their later follow-up indicates non-fatal postoperative events predict reduced late survival, independent of cardioplegia. A minority of studies suggested a benefit of cold cardioplegia over warm in particular patient subgroups: One group conducted a retrospective study of 520 patients who required prolonged aortic cross-clamp times, results demonstrated less myocardial damage and reduced postoperative cardiac mortality and morbidity in the cold group. The clinical bottom line is that warm and cold cardioplegia result in similar short-term mortality. However, large studies have shown that warm cardioplegia reduces adverse post-operative events; the significance of which is unclear.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: is limited pulmonary resection equivalent to lobectomy in terms of morbidity, long-term survival and locoregional recurrence in patients with stage I non-small-cell lung cancer (NSCLC)? A total of 166 papers were found using the reported search; of which, 16 papers, including one meta-analysis and one randomized control trial (RCT), represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. With regards to 5-year survival rates, the evidence is conflicting: a 2005 meta-analysis and six other retrospective or prospective nonrandomized analyses did not find any statistically significant difference when comparing lobectomy with limited resection. However, three studies found evidence of a decreased overall survival with limited resection, including the only randomized control trial, which showed a 50% increase in the cancer-related death rate (P = 0.09), and a 30% increase in the overall death rate in patients undergoing limited resection (P = 0.08). Age, tumour size and specific type of limited resection were also factors influencing the survival rates. Four studies, including the RCT, found increased locoregional recurrence rates with limited resection. There is also evidence that wedge resections, compared with segmentectomies, lead to lower survival and higher recurrence rates. In conclusion, lobectomy is still recommended for younger patients with adequate cardiopulmonary function. Although limited resection carries a decreased rate of complications and shorter hospital stays, it may also carry a higher rate of loco-regional recurrences. However, limited resection may be comparable for patients >71 years of age, and those with small peripheral tumours.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether remote ischaemic preconditioning (RIPC) is of benefit to patients undergoing cardiac surgery. Altogether, more than 264 papers were found using the reported search, 16 of which represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that RIPC is a safe protocol which could potentially be used in cardiac surgery to provide additional cardiac protection against ischaemia reperfusion injury, although it may not be appropriate for patients on K(+) ATPase channel blockers (sulphonylureas) as they seem to eliminate the effect of RIPC. In our study, we found two meta-analyses of cardiac surgery with or without RIPC. Both unequivocally showed 0.81 and 0.74 standardized mean reduction in myocardial necrosis markers in patients receiving RIPC and cardiac or vascular surgery. No difference in perioperative myocardial infarction incidence or 30-day mortality were found. In adult cardiac surgery, we found 11 randomized control trials (RCTs) ranging in size from 45 to 162 patients. Two representative studies reported no difference in postoperative cardiac troponin I concentration in RIPC vs. controls. In one of the studies (CABG ± RIPC) no additional benefit could have been observed for RIPC regarding intra-aortic balloon pump usage (controls 8.5 vs. RIPC 7.5%), inotropic support (39 vs. 50%) or vasoconstrictor usage (66 vs. 64%). On the other hand, in the other study [CABG ± AVR (aortic valve replacement) ± RIPC] significant reduction of troponin I at 8 h postoperatively (controls, 2.90 µg/l vs. RIPC, 2.54 µg/l, P = 0.043) was shown. Marked reduction in cardiac necrosis markers was also found in several smaller RCTs concerning coronary artery bypass grafting (CABG) patients receiving RIPC preoperatively: with cold crystalloid cardioplegia (44.5% reduction), with cross-clamping and fibrillation (43% reduction) and with cold blood cardioplegia (42.4% reduction). The proof of concept trials summarized here give some early evidence that RIPC may potentially provide some reduction in myocardial injury. If confirmed, in future clinical studies this technique may one day lead to a method to reduce reperfusion injury in clinical practice.

A best-evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether screening asymptomatic individuals for an abdominal aortic aneurysm (AAA) is feasible and improves disease-free survival. Seven studies presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and limitations of the studies are tabulated. In total, four randomized population-based studies have evaluated ultrasound screening for AAA: two British studies, Multicentre Aneurysm Screening Study (MASS) and the Chichester trial, and one each in Viborg County, Denmark and Western Australia. Participants were randomized to receive an invitation to screen or not. The MASS trial randomized 67 770 men, followed participants over 10 years and concluded that screening would almost half AAA-related deaths in men aged 65–74 years. The smaller Chichester trial included only 6040 men but demonstrated a 42% reduction in AAA-related mortality at 5 years, with ongoing benefit at 15 years (11% reduction). The Viborg County trial recruited 12 639 men aged 64–73 years, showed a 66% reduction in AAA-related mortality over 14 years. Finally, the Western Australia trial evaluated 41 000 men but included an older population of 65–83 years old. No benefit was seen in this age group but subgroup analysis of men aged 65–74 showed a significant mortality benefit. Only a small or insignificant benefit in all-cause mortality was seen in any of these studies. A recent meta-analysis of these trials has shown a significant benefit in AAA-related mortality in the long term and concluded that AAA screening is superior to other established screening programmes. The cost-effectiveness of screening was assessed in the MASS and Viborg County trials and was found to be substantially below the cost threshold set by the National Institute of Clinical Excellence for acceptance of interventions. Quality of life was assessed in the MASS and in a case–control study and showed no adverse effects that outweigh the benefits. We concluded that ultrasound screening for AAAs has met all the criteria to become a screening programme and would substantially reduce disease-related death with no adverse effect on quality of life.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether manual palpation of the lung is necessary in patients undergoing pulmonary metastasectomy. In total, 56 articles were found using the described search strategy. After screening these articles and their references, 18 publications represented the best evidence to answer the clinical question. No randomized controlled trial addressing the three-part question was available. The authors, journal, date and country of publication, patient group, study type, relevant outcomes and results of these papers were tabulated. The studies reported on 1472 patients with different primary cancers. The patients underwent more than 1630 pulmonary metastasectomies between 1990 and 2014 after the treatment of primary cancer. Almost three quarters of patients underwent open procedures like thoracotomy or sternotomy. Most frequently, helical CT with a slice thickness ranging between 1 and 10 mm was used for preoperative imaging. The sensitivity in detecting pulmonary nodules ranged from 34 to 97%. The corresponding sensitivity rates for PET-CT were 66-67.5 and 75% for high-resolution CT. The positive predictive value for lesions detected by helical CT varied from 47 to 96%. Helical CT reached a specificity between 54 and 93% in detecting pulmonary nodules. The surgeons identified more nodules by meticulous palpation than helical CT. It is noteworthy that up to 48.5% of these palpated nodules were benign lesions (false-positive). Patients with smaller imaged nodules, multiple imaged nodules or primary mesenchymal tumour are more likely to have occult pulmonary nodules. We conclude that not all palpable pulmonary nodules can be imaged preoperatively. Thoracotomy allows the manual palpation of the ipsilateral hemithorax and might be superior to video-assisted thoracic surgery regarding radical resection. However, not all palpable nodules are malignant, and the impact of non-resected pulmonary metastases on patient survival is not clearly evaluated.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was: ‘in patients undergoing oesophagectomy, does a minimally invasive approach convey a benefit in hospital length of stay (LOS), when compared to an open approach?’ A total of 647 papers were identified, using an a priori defined search strategy; 24 papers represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group, study type, relevant outcomes and key results are tabulated. Of the studies identified, data from two randomized controlled trials were available. The first randomized study compared the use of open thoracotomy and laparotomy versus thoracoscopy and laparoscopy. Those undergoing minimally invasive oesophagectomy (MIO) left hospital on average 3 days earlier than those treated with the open oesophagectomy (OO) technique (P = 0.044). The other randomized trial, which compared thoracotomy with thoracoscopy and laparoscopy, demonstrated a reduction of 1.8 days in the LOS when employing the MIO technique (P < 0.001). With the addition of the remaining 22 non-randomized studies, comprising 3 prospective and 19 retrospective cohort studies, which are heterogeneous with regard to their design, study populations and outcomes; data are available representing 3173 MIO and 25 691 OO procedures. In total, 13 studies (including the randomized trials) demonstrate a significant reduction in hospital LOS associated with MIO; 10 suggest no significant difference between techniques; and only 1 suggests a significantly greater length of stay associated with MIO. The only two randomized trials comparing MIO and OO demonstrated a reduction in length of stay in the MIO group, without compromising survival or increasing complication rates. All bar one of the non-randomized studies demonstrated either a significant reduction in length of stay with MIO or no difference. The benefit in reduced length of stay was not at the cost of worsened survival or increased complications, and conversion rates in all studies were low.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was, in patients with previous internal mammary artery/internal thoracic artery (ITA) grafts, can the internal mammary artery/ITA be reused/recycled in redo coronary artery bypass surgery? Fourteen papers were found using the reported search of which 10 represented the best evidence to answer the clinical question. There was variation in patient selection, the number of patients reported, outcome measures recorded, and methods and duration of follow-up. The results were mostly in favour of using a recycled ITA when it could be safely harvested. Most studies were retrospective. One large series of 60 patients who underwent redo coronary artery bypass grafting (CABG) using previously implanted ITAs had a mean time to reoperation of 117 ± 68 months. They reported no operative deaths; no patients required further or subsequent target vessel revascularization; 30-day mortality was 8.3% and myocardial infarction rate was 3%. Another two series of 16 and 12 patients underwent recycling of arterial grafts during coronary artery revascularization with no perioperative deaths in either. Postoperative angiography was performed in 10 patients in one of these studies, which showed excellent flow in all redone left internal thoracic artery (LITA) grafts. One study reported results from a prospective cohort of 9 patients who underwent redo coronary artery bypass grafting. Interval between operations was between 1 and 132 months. There was no perioperative mortality, but 1 patient required reintervention (to an interposition vein graft). A further study of 4 patients who underwent redo CABG using ITAs that were patent but with severe stenosis at the distal anastomosis had no mortality. Postoperative angiography showed patency of all grafts. There have also been 4 case reports on reusing the ITA/ITA in redo CABG with no damage to the reused LITA, no perioperative mortality and satisfactory follow-up at up to 29 months. Evidently, the recycled ITA can be used in redo coronary artery bypass grafting. Papers found were retrospective series or case reports. As such, there is no direct comparison in outcomes between the recycled ITA and first-time ITA harvest or any other conduit for CABG. In conclusion, we find that when it is possible to harvest a previously used ITA, studies have shown it to be a safe and viable conduit in redo CABG with good long-term outcomes.

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was ‘Can lungs be taken for transplantation from donors with a significant smoking history?’. Five papers were found using the reported search that represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. These studies compared the outcome and survival between patients who receive lungs from smokers with those receiving non-smoker lungs. None of these studies were randomized controlled trials. They retrospectively analysed a cohort of patients undergoing lung transplantation for the past 10 years. These studies showed worse outcomes in the early postoperative period, such as longer intensive care unit stay, longer ventilation time and higher early postoperative mortality, with lungs harvested from smokers. Two studies also demonstrated a worse long-term outcome in recipients of lungs from smokers, whereas the other two showed worse results during the early postoperative period only. These latter two studies reported similar survival rates after 3 months and up to 3 years in recipients receiving smoker vs non-smoker lungs. One study, however, showed a better 5-year survival with smoker lungs compared with non-smokers, although in this study, lungs from heavy smokers showed the worse outcome. Despite the difference in long-term results and outcome reported by these authors, all of these studies unanimously indicate that lungs from smokers should not be rejected, as survival in these patients receiving smoker lungs is still significantly higher in 3 and 5 years compared with that in those who remain on the transplant waiting list. In conclusion, the current evidence in the literature suggests that lungs from smokers can be used for transplantation. Patients should, however, be fully informed of the risks involved with these lungs and the worse outcome compared with those receiving non-smoker lungs.

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was ‘Are frozen sections of mediastinoscopy samples as effective as formal paraffin assessment of mediastinoscopy samples for a decision on a same-day lobectomy?’. Five papers were found using the reported search that represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. These studies compared the efficacy and accuracy of frozen sections (FSs) from mediastinal lymph nodes for staging of patients with lung cancer to determine whether a combined procedure can be planned based on these results and to proceed to thoracotomy and lung resection in cases of negative mediastinal nodes diagnosed by FS. These studies unanimously showed that FS of mediastinal nodes are as accurate as permanent section results and definite histology diagnosis with a sensitivity of >94% and specificity of 100% with no false-positive results. They also confirmed that even in benign lung conditions and other malignancies of the mediastinum, the results of FS are compared with the histology of the node. Based on the current reports, a combined procedure (staging mediastinal nodes by FS and planning for thoracotomy or abandoning thoracotomy) is a safe approach to treat non-small-cell lung cancer (NSCLC). From the patients’ point of view, this approach is superior to the staged procedure (mediastinoscopy followed by lung resection at a later date based on the histology of mediastinal nodes) due to single hospitalization and anaesthesia, however whether it is cost effective or not is debatable. It is also labour-intensive and operator-dependant. In conclusion, the current evidence in the literature suggests that a combined procedure of mediastinal node FS followed by lung resection can be a safe alternative to a staged approach to this disease.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: is extracorporeal membrane oxygenation (ECMO) superior to dedicated ventricular assist device (VAD) in patients with acutely failing allograft following transplantation. Altogether, 162 papers were found using the reported search, of which 8 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Two studies provide data only for ECMO-treated patients, in three, the authors describe their experiences with Levitronix CentriMag and three studies directly compare the outcomes of ECMO and VAD support. The survival ranges from 40 to 74% in patients rescued with ECMO compared with 33-60% in patients supported with dedicated VAD. We conclude that there is insufficient evidence to prefer ECMO over VAD and the optimal modality of mechanical circulatory support (MCS) following heart transplantation should be determined by the surgeon and institutional experience and dependent on the extent and severity of myocardial dysfunction and the presence or absence of associated respiratory insufficiency.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was ‘Which stages of thymoma benefit from adjuvant chemotherapy post thymectomy?’ Altogether more than 150 papers were found using the reported search, of which only eight represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated; these studies have mainly reported the survival and recurrence rates of post-thymectomy patients who received adjuvant radiotherapy or chemoradiotherapy, and adjuvant radiotherapy alone was only used in a small group of patients in these studies. We did not find any randomized controlled trials comparing adjuvant chemotherapy with chemo/radiotherapy and, due to a very small incidence of this tumour, it is unlikely to see any trials in future. Studies were mainly retrospective or institutional reports and showed that, despite the high sensitivity of this tumour to chemotherapy agents and the use of chemotherapy as one of the main treatment modalities in the advanced stages of thymoma, current data are not supporting postoperative chemotherapy as a sole adjuvant treatment in advanced stages of thymoma. We conclude that, in patients with thymoma, surgical resection with or without radiation therapy is the gold standard treatment for early-stage disease (I and II). Adjuvant radiotherapy/chemoradiotherapy should be considered for Masaoka stage III (A and B) or above, and it is also advised to add adjuvant therapy for all patients with cortical fenestration, even in stages I and II. But there is no evidence that chemotherapy alone improves the survival in patients with completely resected stage III and IV thymomas and thymic carcinoma. In patients with extra-radiation field disease, however, the use of chemotherapy can potentially improve survival but no follow-up data on this group of patients are available.

A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether manual closure of the bronchial stump is safer with lower failure rates than mechanical closure using a stapling device following anatomical lung resection. One hundred and twenty-nine papers were identified using the search below. Eight papers presented the best evidence to answer the clinical question as they included sufficient number of patients to reach conclusions regarding the issues of interest for this review. Complications, complication rates and operation time were included in the assessment. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. When looking at manual vs mechanical staples, it was noted that stapler failure can occur in around 4% of cases. The rate of bronchopleural fistula (BPF) development varied more in patients who underwent manual closure (1.5–12.5%) than in patients who underwent mechanical closure (1–5.7%). Although most of the studies reviewed showed no statistical differences between manual and mechanical closure in terms of BPF development, one study, however, showed that manual closure was significantly associated with lower numbers of postoperative BPF, while another study showed that mechanical closure is significantly associated with lower incidence of BPF. When looking at the role of the learning curve and training opportunities, it seems that the surgeon's inexperience when using mechanical staples can contribute to BPF development. A surgeon's experience can play a major role in the prevention of BPF development in patients having manual closure. Manual closure can provide a cheap and reliable technique when compared with costs incurred from using staplers, it is applicable in all situations and can be taught to surgeons in training with an acceptable risk. However, there is a lack of evidence to suggest that manual closure is better than mechanical stapler closure following anatomical lung resection.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: ‘Does the use of bilateral mammary artery grafts compared with the use of a single mammary artery graft offer a long-term survival benefit in patients undergoing coronary artery bypass surgery?’ Altogether 214 papers were found using the reported search, of which 13 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All the included studies were follow-up studies; eight studies used prospective data collection, and five studies collected the study data retrospectively. No randomized controlled trials were found. Nine of the 13 included papers used a propensity-score-matched comparison of the survival of bilateral mammary artery graft [or, bilateral internal thoracic artery (BITA) graft] patients vs single mammary artery graft [or, single internal thoracic artery (SITA) graft] patients. These studies consistently showed an enhanced survival of BITA patients compared with propensity-score-matched SITA patients. Three of the 13 included papers used Cox proportional hazards regression analysis to compare survival of BITA vs SITA patients; one larger study showed better crude survival of BITA patients, but did not identify BITA grafts as independent predictor of enhanced survival. The remaining two studies also did not identify BITA grafts as independent predictor of enhanced survival. One study only presented crude survival estimates of BITA vs SITA patients and therefore was of limited informative value. We conclude that the use of BITA grafts seems to offer a long-term survival benefit compared with a SITA graft for patients undergoing coronary artery bypass grafting surgery. Although randomized evidence is lacking, observational evidence supporting this hypothesis is mounting.

We read with great interest the paper by Reeb et al. [1] regarding the utility of daily routine (DR) chest radiographs following pulmonary surgery. They concluded that the on-demand (OD) strategy of obtaining chest X-rays only when clinically indicated, led to equivalent outcomes while reducing radiation exposure and cost of care. Rather than completely do away with DR chest X-rays, it would be interesting to try and identify subgroups of patients who may benefit from this strategy. Earlier studies suggested that pulmonary or unstable cardiac patients, and patients with pulmonary artery catheters, needed daily X-ray monitoring. The American College of Radiology (ACR) previously recommended DR chest radiographs for patients with acute cardiopulmonary problems and those on mechanical ventilation. They have since revised the ACR Appropriateness Criteria in 2011, to favour the more selective OD approach [2]. Cerfolio et al. have found that DR chest X-rays are warranted in post-thoracotomy patients who are hypoxic [1]. In this sub-group, 79% of patients had a radiological finding that influenced their care. Oba et al. [3] however, were not able to identify any sub-population of critically ill patients, who would benefit from DR chest X-rays. The OD strategy has slowly gained acceptance in clinical practice. Graat et al. [4] reported in 2006, that although intensivists doubted the value of DR chest radiography, they were still reluctant to change their practice. More recently, the RadioDay study [5] found that two-thirds of French intensive care units had moved over to ordering chest X-rays on an OD basis. The hesitation to abandon the traditional approach may be related to the comfort level of the intensive care team, and the objectivity of a chest X-ray from a clinical and medico-legal standpoint. Another caveat is, that patients will have to be more closely monitored for changes in their cardiopulmonary status for the OD approach to be successful. Pending the results of further studies, the most efficient plan for utilization of resources may have to be tailored to each individual patient in order to achieve the best outcome. Conflict of interest: none declared.

The radial artery (RA) is often selected as the next conduit of choice following the internal thoracic artery for coronary artery bypass grafting operations (CABG). Radial access coronary angiography (RA-CA) has grown in popularity among cardiologists and has been advocated as the access route of choice for coronary angiography and intervention by many groups. However, sheath insertion and instrumentation may lead to structural and functional damage to the RA, which may preclude its use as a bypass conduit. The increasing use of RA-CA may therefore have an adverse effect on the ability to use the RA as a bypass conduit at subsequent CABG. To review this, a best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was: ‘should the radial artery be used as a bypass conduit following radial access coronary angiography’? Altogether, 167 papers were found using the reported search; 11 papers were identified that provided the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these studies were tabulated. Acute RA occlusion occurs in 2.3–30.5% of patients undergoing RA-CA. While a significant number of occluded RA's show recanalization on early follow-up, markers of endothelial function such as intima-media thickening (IMT) and flow-mediated dilatation remain impaired. RA-CA causes structural injury to the RA with evidence of histological injury (including intimal hyperplasia, periarterial tissue/fat necrosis and adventitial inflammation) along with intimal tears and medial dissections evident along the entire length of the vessel. Only one paper directly assesses patency rates of RA's used as bypass grafts following RA-CA finding a significant adverse effect on graft patency (77% patency in RA-CA, compared with 98% in the control group). We recommend avoiding the RA as a bypass conduit if it has previously been used for RA-CA. In situations where conduit options are limited, if possible, the RA should be avoided for at least 3 months following RA-CA and it may be beneficial to assess the RA's patency and flow characteristics with Doppler ultrasound preoperatively.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: Is perioperative corticosteroid administration associated with a reduced incidence of postoperative atrial fibrillation (POAF) in adult cardiac surgery? A total of 70 papers were identified using the search as described below. Of these, eight were identified to provide best evidence to answer the clinical question. These papers consisted of well-designed, double-blinded randomized control trials (RCTs) or meta-analysis of RCTs that presented sufficient data to reach conclusions regarding the issues of interest for this review. Postoperative atrial fibrillation occurrence, outcomes and complications were included in the assessment. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of the papers are tabulated. Literature search showed that the prophylactic use of hydrocortisone (100 mg/day, 4 days) can reduce the incidence of POAF to 30%, compared with 48% in the control group (P = 0.004). One gram of methylprednisolone before surgery followed by 4 mg of dexamethasone every 6 h for 1 day after surgery was also associated with a significant reduction in POAF (21 vs 51%; P = 0.003). Moreover, a single dose of dexamethasone (0.6 mg/kg) can significantly diminish POAF (18.95 vs 32.3%; P = 0.027). The changes in POAF appeared greatest in patients receiving intermediate doses of corticosteroid (50–210 mg of dexamethasone equivalent), while both lower (up to 8 mg) and higher (236–2850 mg) dosing resulted in blunted effects. Similarly, a moderate dose of hydrocortisone (200–1000 mg/day) is as effective as high (1001–10 000 mg/day) and very high doses (10 000 mg/day). Although the optimal dose, dosing interval and duration of therapy are unclear, meta-analysis suggests that a single dose can be as effective as multiple doses. No statistically significant complications associated with the use of corticosteroids were reported in any of the studies. We conclude that a single prophylactic moderate dose of corticosteroid (50–210 mg of dexamethasone equivalent or 200–1000 mg/day hydrocortisone) can significantly reduce the risk of POAF with no significant increase in morbidity or mortality.

A best evidence topic was written according to a structured protocol. The question addressed was whether cryoanalgesia improves post-thoracotomy pain and recovery. Twelve articles were identified that provided the best evidence to answer the question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were pain scores, additional opiate requirements, incidence of hypoesthesia and change in lung function. Half of the articles reviewed failed to demonstrate superiority of cryoanalgesia over other pain relief methods; however, additional opiate requirements were reduced in patients receiving cryoanalgesia. Change in lung function postoperatively was equivocal. Cryoanalgesia potentiated the incidence of postoperative neuropathic pain. Further analysis of the source of cryoanalgesia, duration, temperature obtained and extent of blockade revealed numerous discrepancies. Three studies utilized CO2 as the source of cryoanalgesia and four used nitrous oxide, but at differing temperatures and duration. Five studies did not reveal the source of cyroanalgesia. The number of intercostal nerves anaesthetized in each study varied. Seven articles anaesthetized three intercostal nerves, three articles used five intercostal nerves, one article used four intercostal nerves and one used one intercostal nerve at the thoracotomy site. Thoracotomy closure and site of area of chest drain insertion may have a role in postoperative pain; but only one article explained method of closure, and two articles mentioned placement of chest drain through blocked dermatomes. No causal inferences can be made by the above results as they are not directly comparable due to confounding variables between studies. Currently, the evidence does not support the use of cryoanalgesia alone as an effective method for relieving post-thoracotomy pain.