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The Nab experiment will measure the ratio of the weak axial-vector and vector coupling constants $\lambda=g_A/g_V$ with precision $\delta\lambda/\lambda\sim3\times10^{-4}$ and search for a Fierz term $b_F$ at a level $\Delta b_F, Comment: Proceedings of the 7th International Syposium on Symmetries in Subatomic Physics SSP2018, Aachen (Germany), 10 - 15 Jun 2018. This is a pre-print of an article published in Hyperfine Interactions. The final authenticated version is available online at: https://doi.org/10.1007/s10751-018-1538-7

Initial validation and feasibility for the Post-operative Quality of Recovery Scale (PQRS) was published in 2010. Ongoing validation includes studies to determine whether this scale can discriminate differences in recovery between cohorts.A prospective cohort study included 61 patients, 18-40 years, and 61 patients, aged ≥ 65 years, undergoing knee arthroscopy under general anaesthesia; and 13 patients, aged ≥ 65 years, undergoing total knee replacement under general anaesthesia. Patients were assessed using the PQRS. Assessments were performed pre-surgery, at 15 and 40 min, 1 and 3 days, and 3 months after surgery.The effect of age was assessed by comparing young versus older arthroscopy patients. There were minimal differences in recovery profiles, other than for the nociceptive domain, where pain recovery was significantly better in the older arthroscopy patients (P0.001). The effect of surgery was assessed by comparing older patients undergoing knee arthroscopy with knee replacement patients. Recovery was significantly worse for the knee replacement group for cognition (P = 0.015), nociception (pain and nausea, P0.001), activities of daily living (P0.001), emotive recovery (P = 0.029), and all-domains recovery (P0.001). Despite differences in quality of recovery, satisfaction was high in all cohorts.Knee replacement had a large effect on recovery compared with knee arthroscopy. Age had minimal effect on recovery after knee arthroscopy. The study showed the ability of the PQRS to discriminate recovery in different domains.

Initial validation and feasibility of the Post-Operative Quality of Recovery Scale (PQRS) was published in 2010. Ongoing validation includes studies to determine whether this scale can discriminate differences in recovery in similar patients having different surgery.A prospective observational study included 89 patients undergoing nasal surgery and 46 patients undergoing tonsillectomy as the primary surgical procedure. Patients were assessed using the PQRS. Assessments were performed pre-surgery, at 15 and 40 min, 1 and 3 days, and 3 months after surgery.Tonsillectomy patients were younger [25.0 standard deviation (SD) 17.8 vs. 32.1 SD 18.0 years, P = 0.031] and had shorter anaesthesia duration (29.5 SD 12.6 vs. 42.7 SD 15.8 min, P 0.01). Tonsillectomy patients had worse recovery in the nociceptive (pain and nausea; P 0.001), activities of daily living (P 0.001) and overall recovery (P = 0.025) domains, but were not different in the cognitive, emotive (depression and anxiety) or physiological recovery domains. Complete satisfaction was lower for tonsillectomy (P 0.001). At 3 months, there was equivalence between groups in all assessments.The study shows the ability of the PQRS to discriminate recovery in different domains. Tonsillectomy has a worse recovery profile over the first 3 days in nociceptive, activities of daily living and overall recovery, which is associated with poorer satisfaction than nasal surgery.

Background . Total arterial coronary revascularization can be achieved by joining arteries together as a composite graft with the proximal left internal mammary artery as the only source of blood inflow. Proof of the capacity of this composite conduit to provide adequate blood flow to the coronary circulation is required. Methods . The radial artery was anastomosed to the left internal mammary artery as a Y graft in 17 patients and all coronary arteries grafted. Intraoperative blood flow through the composite grafts was evaluated by the transit-time Doppler technique. Results . Against no resistance, blood flow in the left internal mammary artery alone was 99 ± 9 mL/min and rose to 173 ± 16 mL/min when the radial artery was anastomosed as a Y graft. Composite-graft flow following grafting was 88 ± 9 mL/min, 49 ± 6 mL/min when the aortic clamp was removed and native coronary flow restored and 82 ± 13 mL/min following weaning from cardiopulmonary bypass. The maximal potential flow through the composite graft was 2.3-fold (95% CI 1.6 to 3.2) greater than that after cardiopulmonary bypass. Conclusions . Total arterial revascularization, using a composite graft, provided a 2.3-fold reserve of blood flow to the coronary vascular bed through the grafts.

Cognitive problems early after surgery are often considered transient in nature. Neuropsychological performance and its relation to other recovery parameters have rarely been systematically assessed during this period.A subanalysis of the Post-operative Quality of Recovery Scale (PQRS) feasibility study included patients who completed the PQRS on day 3, and were categorised as recovered or not recovered in the cognitive domain using the revised scoring method.Of the 449 patients included in this paper, 388 (86.4%) recovered in the cognitive domain and 61 (13.6%) had not recovered at 3 days. Cognitive recovery in the early post-operative time points up to day 1 was significantly lower in patients who had not recovered at day 3 (P 0.001). Of those not recovered on day 3, 59.1% had recovered on day 1, but lapsed to non-recovery on day 3. The non-recovered group demonstrated less recovery in the physiological (P = 0.019), activity of daily living (P = 0.049) and nociceptive (P = 0.033) domains, but no difference was found in the emotive domain. The non-recovered group had a higher incidence of major surgery (P = 0.021), a higher proportion of patients with difficulty eating (4.9% vs. 0.5%, P = 0.002 and a clinically unimportant but lower temperature (36.6° vs. 36.4°C, P = 0.010).Failure of cognitive recovery is reasonably common 3 days after surgery, can fluctuate and is associated with poorer early recovery in the activities of daily living, nociceptive and physiological domains.

Hip fracture surgery is associated with a high rate of mortality and morbidity; heart disease is the leading cause and is often unrecognised and inadequately treated. Pre-operative focused transthoracic echocardiography by anaesthetists frequently influences management, but mortality outcome studies have not been performed to date. Mortality over the 12 months after hip fracture surgery, in 64 patients at risk of cardiac disease who received pre-operative echocardiography, was compared with 66 randomised historical controls who did not receive echocardiography. Mortality was lower in the group that received echocardiography over the 30 days (4.7% vs 15.2%, log rank p=0.047) and 12 months after surgery (17.1% vs 33.3%, log rank p=0.031). Hazard of death was also reduced with pre-operative echocardiography over 12 months after adjustment for known risk factors (hazard ratio 0.41, 95% CI 0.2-0.85, p=0.016). Pre-operative echocardiography was not associated with a delay in surgery. These data support a randomised controlled trial to confirm these findings.

This prospective observational study investigated the effect of focused transthoracic echocardiography in 99 patients who had suspected cardiac disease or were ≥ 65 years old, and were scheduled for emergency non-cardiac surgery. The treating anaesthetist completed a diagnosis and management plan before and after transthoracic echocardiography, which was performed by an independent operator. Clinical examination rated cardiac disease present in 75%; the remainder were asymptomatic. The cardiac diagnosis was changed in 67% and the management plan in 44% of patients after echocardiography. Cardiac disease was identified by echocardiography in 64% of patients, which led to a step-up of treatment in 36% (4% delay for cardiology referral, 2% altered surgery, 4% intensive care and 26% intra-operative haemodynamic management changes). Absence of cardiac disease in 36% resulted in a step-down of treatment in 8% (no referral 3%, intensive care 1% or haemodynamic treatment 4%). Pre-operative focused transthoracic echocardiography in patients admitted for emergency surgery and with known cardiac disease or suspected to be at risk of cardiac disease frequently alters diagnosis and management.

Patients with suspected or symptomatic cardiac disease, associated with increased peri-operative risk, are often seen by anaesthetists in the pre-assessment clinic. The use of transthoracic echocardiography in this setting has not been reported. This prospective observational study investigated the effect of echocardiography on the anaesthetic management plan in 100 patients who were older than 65 years or had suspected cardiac disease. Echocardiography was performed by an anaesthetist, and was validated by a cardiologist. Overall, the anaesthetic plan was changed in 54 patients. Haemodynamically significant cardiac disease was revealed in 31 patients, resulting in a step-up of treatment in 20 patients, including: cardiology referral (four patients); altered surgical (two) and anaesthetic (four) technique; use of invasive monitoring (13); planned use of vasopressor infusion (10); and postoperative high dependency care (five). Reassuring negative findings in 69 patients led to a step-down in treatment in 34 patients: altered anaesthetic technique (six); procedure not cancelled (10); cardiology referral not made (10); use of invasive monitoring not required (seven); and high dependency care not booked (11). We conclude that focused transthoracic echocardiography in the pre-operative clinic is feasible and frequently alters management in patients with suspected cardiac disease.

The objective of this study was to identify whether pulmonary capillary wedge pressure can be estimated in anaesthetised patients receiving mechanical ventilation, using transoesophageal echocardiography. A retrospective validation study investigated a 10-patient cohort with variable haemodynamic conditions, and a 102-patient series in which a single measurement was made during stable haemodynamic conditions. Concurrent echocardiographic Doppler and pulmonary artery catheter wedge pressure measurements were performed. In the 10-patient cohort, the systolic fraction of Doppler measurements in the pulmonary vein (r = -0.32, p = 0.035) and the E/A ratio (r = 0.56, p = 0.0009) were correlated with the wedge pressure. In all cases, the limits of agreement exceeded 10 mmHg, and sensitivity or specificity for detecting wedge pressure ≥ 15 mmHg was poor. This study demonstrates proof of concept that using transoesophageal echocardiography for estimating the pulmonary artery wedge pressure may not be sufficiently accurate for clinical use.

We investigated the influence of either propofol or desflurane on the incidence of postoperative cognitive dysfunction in a randomised trial of 180 patients undergoing coronary artery bypass surgery. The primary outcome was incidence of postoperative cognitive dysfunction at 3 months, defined as ≥1 SD deterioration in two or more of 12 neurocognitive tests. Secondary outcomes included early postoperative cognitive dysfunction (between days three and seven), delirium on day one, morbidity and length of hospital stay. Early postoperative cognitive dysfunction was significantly higher with propofol compared with desflurane (56/84 (67.5%) vs 41/83 (49.4%), respectively, p=0.018), but this effect was not seen at 3 months (10/87 (11.2%) vs 9/90 (10.0%), respectively. There was no difference in delirium (7/89 (7.9%) vs 12/91 (13.2%), respectively, length of hospital stay (median (IQR [range]) 7 (6-9 [4-15]) vs 6 (5-7 [5-16) days, respectively or other morbidities. Desflurane was associated with reduced early cognitive dysfunction.

Miniaturization of ultrasound equipment has led to the development of hand-held echocardiography devices suitable for bedside evaluation of cardiac function. Basic assessment of the haemodynamic state can be performed using a limited transthoracic echocardiography examination. This study evaluated a third generation device (SonoSite Titan) used by novice and expert operators. Limited transthoracic examination was performed on 30 healthy volunteers by an expert and a novice operator. The novice had performed 10 studies prior to data accrual. Agreement analysis was performed using weighted least products regression and Bland-Altman analysis. Acceptable results for the novice were achieved following 20 studies (including practice sessions) for basic haemodynamic assessment and following 40 studies for all measured parameters. The SonoSite Titan is acceptable for basic transthoracic measurements to determine the basic haemodynamic state and cardiac output measurements. We recommend a minimum of 20 training studies for novice operators prior to clinical use.

When used as an adjunct to local anaesthetic, opioid administered via the epidural route can improve the quality of analgesia. Reports of respiratory depression associated with epidural morphine use as a sole agent in the 1980s led to an increased use of lipophilic opioids, especially fentanyl. Although fentanyl is commonly used, controversy exists about its efficacy and site of action. It is possible that low-dose morphine may be more effective than fentanyl, without increasing the risk of respiratory depression. A retrospective audit was conducted of 200 consecutive patients undergoing coronary artery bypass surgery who received high thoracic epidural analgesia. One hundred patients who received fentanyl 2 μg/ml with 0.2% ropivacaine, prior to a change in our technique, were audited, followed by 100 patients who received 20 μg/ml morphine with 0.2% ropivacaine. Outcome measures included the incidence of Visual Analogue Score (VAS) ≥4/10; infusion rate adjustments; and side-effects. Patients receiving fentanyl were more likely to experience pain ≥4/10 (P'=0.002); the infusion rate was higher (P8=0.024); required more rate adjustments (P8=0.001); a greater need for noradrenaline (P'=0.001) and antiemetic drugs (P'=0.001). There were no significant differences between the groups for sedation scores or the incidence of respiratory depression. This audit suggests morphine 20 μg/ml may be superior to fentanyl 2 μg/ml, as an adjunct to 0.2% ropivacaine. We found a reduced number of infusion interventions and less inadequate patient analgesia.

We aimed to assess whether movement of the interatrial septum predicts change in pulmonary capillary wedge pressure (PCWP). In 71 patients undergoing cardiac surgery, the interatrial septum was categorised by its shape and movement using transesophageal echocardiography. Fixed curvature (FC) was identified by bowing of the interatrial septum from left to right throughout the cardiac cycle, mid-systolic reversal (MSR) by minimal septal movement and transient reversal (right to left) during mid-systole, and mid-systolic buckling (MSB) by marked movement and buckling of the septum during mid-systole. These were compared with PCWP. Sensitivity and interobserver reliability was studied with continuous PCWP and TEE measurement during a period of acute volume alteration in 10 additional patients. Interatrial septal movement predicted PCWP, with mean PCWP (95% confidence intervals) for FC, 18.1 mmHg (16.7 to 19.6), MSR 13.2 mmHg (12.5 to 13.8) and MSB, 9.9 mmHg (9.0 to 10.7) mmHg. The mean PCWP at which a change in pattern occurred was 8.9 mmHg (8.3 to 9.6) for MSR to MSB, and 10.9 mmHg (10.1 to 11.8) for MSR to FC (p0.001). There was no significant difference in mean values for all three observers. Movement of the interatrial septum predicts change in PCWP.

Afterload corrected fractional area change (FACac) is a simple measurement of contractility which can be acquired during surgery without the need to acutely alter volume. We have validated it against the load-independent measurement, stroke force / end-diastolic area relationship (SF/EDA) in patients undergoing cardiac surgery. SF/EDA regressions were analysed before and after cardiopulmonary bypass in 39 patients and compared with simultaneously acquired FACac data. End-systolic and end-diastolic areas (ESA and EDA) were measured by transesophageal echocardiography and substituted for ventricular volumes. Pulmonary capillary wedge pressure was substituted for end-diastolic pressure and peak-systolic pressure for end-systolic pressure. Stroke force is the integral of the pressure-area loop and a square shape was assumed for calculation. FACac = FAC x log 10(SVRI) x 100%, where SVRI is calculated without multiplication by 80. Comparison of the methods was done by ordinary least products regression analysis where SF/EDA = a+b (FACac). a = 0.004 (95% CI -5.46 to 5.46). b = 0.857 (95% CI 0.777 to 0.936). Agreement between SF/EDA and FACac was identified by the absence of fixed bias. Both SF/EDA and FACac identified a reduction in contractility following cardiopulmonary bypass of similar magnitude suggesting load-independence of FACac. In contrast, the load-dependent indexes, cardiac index and FAC, increased in value but in the presence of reduced afterload. FACac may be used as a simplified index to reflect a relatively load-independent index of left ventricular contractility. Its simplicity offers promise of clinical utility.

The end-diastolic pressure-volume relation is a load-independent measurement of diastolic function. However, its clinical utility is limited because of its complexity. Instantaneous end-diastolic stiffness (IEDS) is a simple to perform, single-point, measurement of ventricular stiffness. We have validated it against the end-diastolic pressure-area relation (EDPAR) in patients undergoing cardiac surgery. EDPARs were analyzed before and after cardiopulmonary bypass in 29 patients and compared with IEDS. Data was collected in an additional 69 patients in order to estimate the range of values of IEDS. End-diastolic area (EDA) measured by transesophageal echocardiography (TEE) was substituted for end-diastolic volume, and pulmonary capillary wedge pressure (PWCP) was substituted for end-diastolic pressure. IEDS = 100 x (log10 PWCP)/EDA. Comparison of the methods was done by ordinary least products regression analysis. Agreement between EDPAR and IEDS was identified by the absence of fixed and proportional bias. The maximal range of corresponding values identified by 95% confidence intervals was within +/- 16% of the mean indicating satisfactory agreement. The geometric mean and 95% confidence intervals (CI) for IEDS were 8. 7 mmHg/dm2 (8.1 to 9.4) and for IEDS indexed to body surface area were 17.2 mmHg/dm(2)/m2 (16.0 to 18.6). IEDS is a load independent index of left ventricular stiffness.

We compared three techniques of aortic valve area (AVA) measurement using transesophageal echocardiography (TEE) and determined if AVA can be predicted from simple patient or echocardiographic measurements. AVA was simultaneously measured with direct planimetry, the continuity equation and with a novel technique combining stroke volume using thermodilution and continuous wave Doppler. Using planimetry as the reference in patients with normal valves, left ventricular outflow tract area (LVOTA), lean body mass (LBM), body surface area (BSA) and height were assessed as predictors of AVA. All three methods of AVA measurement showed close agreement and can be used interchangeably. Both LVOTA and LBM were predictors of AVA, but LVOTA was better. BSA and height were not acceptable as predictors of AVA. TEE can be used to measure AVA either with planimetry, the continuity equation, or in combination with thermodilution. LVOTA was the best predictor of AVA.

To develop a simple harvest technique for radial artery (RA). To investigate the morbidity and functional outcome of RA harvest.The neurovascular fascia surrounding the RA is divided. Only loose areolar tissue surrounds this artery making harvest of RA simple and allowing minimal trauma to the RA and surrounding muscles. Topical and intraluminal vasodilators but no systemic vasodilators are used.RA harvest commenced in December 1994. Between 1996 and 30 June 1998, 2167 RA were harvested and used to construct 3105 coronary anastomoses. A dramatic rise in RA use occurred during 1996. More than 80% of patients undergoing coronary artery bypass surgery (CABG) have RA harvested since this time. Total arterial revascularization rate also rose dramatically and is currently 80% of all CABG. This rate has been assisted by a rapid rise in the use of composite arterial grafting where aortic anastomoses can be avoided and currently represents 40% of all CABG. Hand strength was tested in 328 non-selected patients and was not reduced by RA harvest when hand dominance was taken into account. Objective sensation loss was present in 0.3% for the superficial radial nerve and 2.1% for the lateral cutaneous nerve of forearm. Pulse oximetry observations detected statistically significant but clinically irrelevant differences. Scar hypersensitivity occurred in 20%. Only two patients of all patients undergoing RA harvest reported late hand ischaemia.Harvest of the RA within the neurovascular plane is simple and associated with low morbidity.

The observation that X-ray methods currently in use for determination of calcite and dolomite in rocks and sediments often give inconsistent results led us to structure an experiment to evaluate their relative accuracy. Three dolomite standards were selected from which 33 mixtures (11 each) of calcite and dolomite were prepared in triplicate (99 total). The intensities of the major calcite and dolomite reflections of each slide were measured by four methods: by fixed-time count on the peak maximum, integral count of a fixed interval across the peak, ruler measurement of peak height and planimeter measurement of peak area. The parameter "dolomite/dolomite plus calcite" was computed for each diffraction pattern. A curve of best-fit and the standard error of this parameter, as a function of weight percent dolomite, were computed for various combinations of individual and average data to determine the relative accuracy of the several types of intensity measures. Results of previous investigators were compared with our data to estimate their relative precision. It is concluded that X-ray peak-height (fixed time) intensity measurement provides the most rapid and precise procedure for determination of calcite and dolomite. Composite data for all types of measurement yield a calibration curve which gives results in terms of weight percent dolomite of about ±6 at the 95% confidence level. Its true accuracy is probably better. Replicate analysis of unknowns yield mean values with standard deviations of about 3, expressed as percent dolomite. Most of the curves presented by prior investigators compare well with ours; that is, they lie within our documented confidence interval, and data derived from them can probably be considered reliable within the limits of accuracy established by this study.