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Cardiac surgery with cardiopulmonary bypass triggers an acute inflammatory response in the lungs. This response gives rise to fibrin deposition in the microvasculature and alveoli of the lungs. Fibrin deposition in the microvasculature increases alveolar dead space, while fibrin deposition in alveoli causes shunting. We investigated whether prophylactic nebulised heparin could limit this form of lung injury. We undertook a single-centre double-blind randomised trial. Forty patients undergoing elective cardiac surgery with cardiopulmonary bypass were randomised to prophylactic nebulised heparin (50,000 U) or placebo. The primary endpoint was the change in arterial oxygen levels over the operative period. Secondary endpoints included end-tidal CO₂, the alveolar dead space fraction and bleeding complications. We found nebulised heparin did not improve arterial oxygen levels. Nebulised heparin was, however, associated with a lower alveolar dead space fraction (P <0.05) and lower tidal volumes at the end of surgery (P <0.01). Nebulised heparin was not associated with bleeding complications. In conclusion, prophylactic nebulised heparin did not improve oxygenation, but was associated with evidence of better alveolar perfusion and CO₂elimination at the end of surgery.

Objectives: Bleeding into the chest is a major cause of blood transfusion and adverse outcomes following cardiac surgery. The authors investigated predictors of bleeding following cardiac surgery to identify potentially correctable factors., Design: Data were retrieved from the medical records of patients undergoing cardiac surgery over the period of 2002 to 2008. Multivariate analysis was used to identify the independent predictors of chest tube drainage., Setting: Tertiary hospital., Participants: Two thousand five hundred seventy-five patients., Interventions: Cardiac surgery., Results: The individual operating surgeon was independently associated with the extent of chest tube drainage. Other independent factors included internal mammary artery grafting, cardiopulmonary bypass time, urgency of surgery, tricuspid valve surgery, redo surgery, left ventricular impairment, male gender, lower body mass index and higher preoperative hemoglobin levels. Both a history of diabetes and administration of aprotinin were associated with reduced levels of chest tube drainage., Conclusions: The individual operating surgeon was an independent predictor of the extent of chest tube drainage. Attention to surgeon-specific factors offers the possibility of reduced bleeding, fewer transfusions, and improved patient outcomes., (© 2014 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Red blood cells (RBC) undergo many changes during storage. Such changes are associated with reduced oxygen-carrying capacity and transfusion-related inflammatory reactions. The clinical significance of these changes in the cardiac surgical setting is unclear. This observational cohort study investigates the association between age of transfused RBC and early outcomes after cardiac surgery., Methods: The cardiac surgery database at St. Vincent's Hospital Melbourne was cross-referenced with the Blood Transfusion Services database. In all, 670 consecutive patients who had nonemergency coronary artery bypass grafting or aortic valve replacement, or both, between June 2001 and June 2007 and had at least 2 RBC units transfused were studied. The storage variables studied were mean age of RBC, age of oldest RBC unit transfused, and transfusion of RBC stored longer than 30 days. Age of transfused blood was analyzed using logistic and linear regression analysis to determine an independent association with clinical outcomes: postoperative early mortality, renal failure, pneumonia, intensive care unit stay, and ventilation hours. Patient preoperative risk profile (EuroSCORE) and total number of RBC units transfused were adjusted for., Results: The storage age of RBC was not independently associated with any of the endpoints studied. The total quantity of RBC transfused was significantly associated with all studied endpoints., Conclusions: Under current transfusion practice, the age of transfused RBC is not associated with early mortality and morbidity after cardiac surgery.

Objective: To assess the prevalence of obesity in patients undergoing coronary artery bypass grafting, heart valve surgery, or both procedures, and its association with postoperative outcomes., Design and Setting: Retrospective analysis of data, collected by the Australasian Society of Cardiac and Thoracic Surgeons Victorian Cardiac Surgery Database Project, on patients undergoing coronary artery bypass grafting, heart valve surgery, or both procedures, between 1 June 2001 and 31 January 2006., Participants: 11 736 patients divided into four groups: underweight (body mass index [BMI], < 20), normal weight (BMI, 20-30), obese (BMI, > 30 to < 40), and morbidly obese (BMI, >/= 40)., Main Outcome Measures: Prevalence of obesity (compared with the age- and sex-matched adult Australian population); associations between obesity and morbid obesity in cardiac patients and adverse postoperative outcomes., Results: 30.4% of patients had a BMI > 30 (28.6% obese, 1.8% morbidly obese) compared with an expected prevalence of 21.2%. Morbid obesity was associated with prolonged ventilation (adjusted odds ratio [OR], 2.4; 95% CI, 1.6-3.7), readmission to intensive care (adjusted OR, 2.2; 95% CI, 1.2-4.1), and length of stay > 14 days (adjusted OR, 2.1; 95% CI, 1.4-3.3). Both obesity and morbid obesity were associated with renal failure (adjusted ORs, 1.4 [95% CI, 1.1-1.7] and 2.9 [95% CI, 1.7-4.9], respectively) and deep sternal wound infection (adjusted ORs, 2.4 [95% CI, 1.5-3.8] and 7.2 [95% CI, 2.8-18.7], respectively)., Conclusions: Obesity is 1.4 times more prevalent in patients having coronary artery bypass grafting or heart valve surgery in Victoria compared with the general adult Australian population. Both obesity and morbid obesity are associated with early morbidity, but not mortality, after operation.

The Cox-Maze III procedure remains the yardstick by which all treatments for atrial fibrillation are measured. This procedure is not widely adopted because of its perceived technical complexity, invasiveness and longer procedural time. Efforts have been made by various investigators to reproduce Dr Cox's results using alternative lesion sets and energy sources. Bipolar radiofrequency (BPRF) ablation avoids the morbidity of cut-and-sew lesions, reduces procedural time and increases the likelihood of transmurality and continuity of lesions created compared to unipolar devices. Initial results are encouraging. We present our surgical technique and early experience using BPRF modification of the Cox-Maze III procedure using the Medtronic Cardioblate BP system.

Background: The prevalence of obesity in most developed nations, including Australia, continues to rise and represent an increasing public health concern. Obesity has been considered a major risk factor in patients undergoing cardiac and other major surgery., Methods: We retrospectively analysed prospectively collected data of consecutive patients undergoing cardiac surgery between June 2001 and February 2006 at two Australian public hospitals. Patients were divided into three groups by body mass index (BMI): non-obese (BMI 20-30), obese (BMI>30-40) and morbidly obese (BMI>40). Associations between early mortality and morbidity and obesity were assessed by univariate and multivariate methods., Results: Out of 4053 patients, 85 were excluded for BMI<20. A total of 2743 patients were defined as non-obese, 1136 obese and 89 morbidly obese. There were no significant differences in operative mortality, stroke, pneumonia, new renal failure, atrial fibrillation, prolonged ventilation, reintubation, readmission to intensive care, prolonged length of hospital stay or readmission within 30 days. The morbidly obese group had increased rates of deep sternal infection by univariate (odds ratio [OR] 6.4, 95% confidence interval [CI] 2.1-19.1, p<0.001) and multivariate (OR 13.1, CI 3.4-50.7, p<0.001) analysis. The obese group had a lower rate of re-operation for bleeding by univariate (OR 0.61, CI 0.41-0.91, p=0.01) and multivariate (OR 0.64, CI 0.42-0.99, p=0.04) analysis., Conclusion: Apart from an increased rate of deep sternal wound infection, obesity is not associated with early mortality or other post-operative complications. The protective effect of obesity on re-operation for bleeding requires further study.

Background: The incidence of surgery for atrial fibrillation (AF) is rising, paralleled by an increase in the types of lesion sets and energy sources used. These alternate energy sources have simplified the surgery at the expense of increased cost of consumables. The classical Cox-Maze III is the gold standard therapy with a proven efficacy in curing AF. Our complete experience with this procedure is presented., Methods: All 28 patients undergoing the classical Cox-Maze III procedure at our institution underwent preoperative assessment and were followed prospectively., Results: Twenty-eight patients underwent the Cox-Maze III procedure between January 2001 and May 2003. Their mean age was 65 years (range, 44-80 years). Twenty-five patients had concomitant cardiac procedures. Mean duration of AF was 8.3 years. Permanent AF was present in 82%. Mean follow-up time was 15 +/- 8 months (range, 4-30 months). There were no perioperative or late deaths, or thromboembolic events. Sixty-one per cent had early (<3 months) atrial arrhythmia. Freedom from AF at most recent clinical follow up was 93%. Freedom from late atrial arrhythmia was 82%. Freedom from late AF or atrial flutter by pacemaker interrogation or Holter assessment was 77%. Anti-arrhythmic medication use was reduced. New York Heart Association class improved from an average of 2.8 preoperatively to 1.3 postoperatively., Conclusion: The result of the present study shows the safety and efficacy of the classical Cox-Maze III procedure. With the advantage of proven long-term efficacy, demonstrable safety and avoidance of costly technology, the Cox-Maze III should not be discounted as a treatment option in patients because of its perceived complexity.

Objective: There is an important role for accurate risk prediction models in current cardiac surgical practice. Such models enable benchmarking and allow surgeons and institutions to compare outcomes in a meaningful way. They can also be useful in the areas of surgical decision-making, preoperative informed consent, quality assurance and healthcare management. The aim of this study was to assess the performance of the European System for Cardiac Operative Risk Evaluation (EuroSCORE) model on the Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) patient database., Methods: The additive and logistic EuroSCORE models were applied to all patients undergoing cardiac surgery at six institutions in the state of Victoria between 1st July 2001 and 4th July 2005 within the ASCTS database who have complete data. The entire cohort and a subgroup of patients undergoing coronary artery bypass grafting (CABG) only were analysed. Observed and predicted mortalities were compared. Model discrimination was tested by determining the area under the receiver operating characteristic (ROC) curve. Model calibration was tested by the Hosmer-Lemeshow chi-square test., Results: Eight thousand three hundred and thirty-one patients with complete data were analysed. There were significant differences in the prevalence of risk factors between the ASCTS and European cardiac surgical populations. Observed mortality was 3.20% overall and 2.00% for the CABG only group. The EuroSCORE models over estimated mortality (entire cohort: additive predicted 5.31%, logistic predicted 8.76%; CABG only: additive predicted 4.25%, logistic predicted 6.19%). Discriminative power of both models was very good. Area under ROC curve was 0.83 overall and 0.82 for the CABG only group. Calibration of both models was poor as mortality was over predicted at nearly all risk deciles. Hosmer-Lemeshow chi-square test returned P-values less than 0.05., Conclusions: The additive and logistic EuroSCORE does not accurately predict outcomes in this group of cardiac surgery patients from six Australian institutions. Hence, the use of the EuroSCORE models for risk prediction may not be appropriate in Australia. A model, which accurately predicts outcomes in Australian cardiac surgical patients, is required.

Background: The purpose of the present paper was to assess the performance of the European system for cardiac operative risk evaluation (EuroSCORE) model in an Australian adult cardiac surgical population., Methods: The additive and logistic EuroSCORE models were retrospectively applied to predict operative mortality in 2106 consecutive patients undergoing cardiac surgery at St Vincent's Hospital, Melbourne between June 2001 and August 2003, and at Geelong Hospital between June 2001 and April 2004. The entire cohort and a subset of patients undergoing isolated coronary artery bypass graft (CABG) surgery were analysed. Model discrimination and calibration was tested by determining the area under the receiver operating characteristic (ROC) curve and Hosmer-Lemeshow chi2, respectively., Results: There were significant differences in the prevalence of risk factors between the Australian and European cardiac surgical populations. There were 81 deaths (observed mortality 3.85%) in the entire cohort and 39 deaths in the isolated CABG group (observed mortality 2.60%). The EuroSCORE models overestimated mortality (entire cohort: additive predicted 5.75%, logistic predicted 9.93%; isolated CABG: additive predicted 4.87%, logistic predicted 7.71%). Discriminative power was very good for the entire cohort (area under ROC curve, 0.81 (additive) and 0.82 (logistic)). Calibration of both models was poor., Conclusion: The additive and logistic EuroSCORE model of risk prediction was not validated in the present population of cardiac surgical patients. The models may not accurately predict outcomes of patients undergoing cardiac surgery in Australia.