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BACKGROUND: An association between increasing anaesthetic depth and decreased postoperative survival has been shown in observational studies; however, evidence from randomised controlled trials is lacking. Our aim was to compare all-cause 1-year mortality in older patients having major surgery and randomly assigned to light or deep general anaesthesia.METHODS: In an international trial, we recruited patients from 73 centres in seven countries who were aged 60 years and older, with significant comorbidity, having surgery with expected duration of more than 2 h, and an anticipated hospital stay of at least 2 days. We randomly assigned patients who had increased risk of complications after major surgery to receive light general anaesthesia (bispectral index [BIS] target 50) or deep general anaesthesia (BIS target 35). Anaesthetists also nominated an appropriate range for mean arterial pressure for each patient during surgery. Patients were randomly assigned in permuted blocks by region immediately before surgery, with the patient and assessors masked to group allocation. The primary outcome was 1-year all-cause mortality. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12612000632897, and is closed to accrual.FINDINGS: Patients were enrolled between Dec 19, 2012, and Dec 12, 2017. Of the 18 026 patients screened as eligible, 6644 were enrolled, randomly assigned to treatment or control, and formed the intention-to-treat population (3316 in the BIS 50 group and 3328 in the BIS 35 group). The median BIS was 47·2 (IQR 43·7 to 50·5) in the BIS 50 group and 38·8 (36·3 to 42·4) in the BIS 35 group. Mean arterial pressure was 3·5 mm Hg (4%) higher (median 84·5 [IQR 78·0 to 91·3] and 81·0 [75·4 to 87·6], respectively) and volatile anaesthetic use was 0·26 minimum alveolar concentration (30%) lower (0·62 [0·52 to 0·73] and 0·88 [0·74 to 1·04], respectively) in the BIS 50 than the BIS 35 group. 1-year mortality was 6·5% (212 patients) in the BIS 50 group and 7·2% (238 patients) in the BIS 35 group (hazard ratio 0·88, 95% CI 0·73 to 1·07, absolute risk reduction 0·8%, 95% CI -0·5 to 2·0). Grade 3 adverse events occurred in 954 (29%) patients in the BIS 50 group and 909 (27%) patients in the BIS 35 group; and grade 4 adverse events in 265 (8%) and 259 (8%) patients, respectively. The most commonly reported adverse events were infections, vascular disorders, cardiac disorders, and neoplasms.INTERPRETATION: Among patients at increased risk of complications after major surgery, light general anaesthesia was not associated with lower 1-year mortality than deep general anaesthesia. Our trial defines a broad range of anaesthetic depth over which anaesthesia may be safely delivered when titrating volatile anaesthetic concentrations using a processed electroencephalographic monitor.FUNDING: Health Research Council of New Zealand; National Health and Medical Research Council, Australia; Research Grant Council of Hong Kong; National Institute for Health and Research, UK; and National Institutes of Health, USA.

BACKGROUND: Globally, >300 million patients have surgery annually, and ≤20% experience adverse postoperative events. We studied the impact of both cardiac and noncardiac adverse events on 1-year disability-free survival after noncardiac surgery. METHODS: We used the study cohort from the Evaluation of Nitrous oxide in Gas Mixture of Anesthesia (ENIGMA-II) trial, an international randomized trial of 6992 noncardiac surgical patients. All were ≥45 years of age and had moderate to high cardiac risk. The primary outcome was mortality within 1 postoperative year. We defined 4 separate types of postoperative adverse events. Major adverse cardiac events (MACEs) included myocardial infarction (MI), cardiac arrest, and myocardial revascularization with or without troponin elevation. MI was defined using the third Universal Definition and was blindly adjudicated. A second cohort consisted of patients with isolated troponin increases who did not meet the definition for MI. We also considered a cohort of patients who experienced major adverse postoperative events (MAPEs), including unplanned admission to intensive care, prolonged mechanical ventilation, wound infection, pulmonary embolism, and stroke. From this cohort, we identified a group without troponin elevation and another with troponin elevation that was not judged to be an MI. Multivariable Cox proportional hazard models for death at 1 year and assessments of proportionality of hazard functions were performed and expressed as an adjusted hazard ratio (aHR) and 95% confidence intervals (CIs). RESULTS: MACEs were observed in 469 patients, and another 754 patients had isolated troponin increases. MAPEs were observed in 631 patients. Compared with control patients, patients with a MACE were at increased risk of mortality (aHR, 3.36 [95% CI, 2.55-4.46]), similar to patients who suffered a MAPE without troponin elevation (n = 501) (aHR, 2.98 [95% CI, 2.26-3.92]). Patients who suffered a MAPE with troponin elevation but without MI had the highest risk of death (n = 116) (aHR, 4.29 [95% CI, 2.89-6.36]). These 4 types of adverse events similarly affected 1-year disability-free survival. CONCLUSIONS: MACEs and MAPEs occur at similar frequencies and affect survival to a similar degree. All 3 types of postoperative troponin elevation in this analysis were associated, to varying degrees, with increased risk of death and disability.

Background Tranexamic acid reduces blood loss and transfusion requirements in cardiac surgery but may increase the risk of coronary graft thrombosis. We previously reported the 30-day results of a trial evaluating tranexamic acid for coronary artery surgery. Here we report the 1-year clinical outcomes. Methods Using a factorial design, we randomly assigned patients undergoing coronary artery surgery to receive aspirin or placebo and tranexamic acid or placebo. The results of the tranexamic acid comparison are reported here. The primary 1-year outcome was death or severe disability, the latter defined as living with a modified Katz activities of daily living score of less than 8. Secondary outcomes included a composite of myocardial infarction, stroke, and death from any cause through to 1 year after surgery. Results The rate of death or disability at 1 year was 3.8% in the tranexamic acid group and 4.4% in the placebo group (relative risk, 0.85; 95% confidence interval, 0.64-1.13; P = .27), and this did not significantly differ according to aspirin exposure at the time of surgery (interaction P = .073). The composite rate of myocardial infarction, stroke, and death up to 1 year after surgery was 14.3% in the tranexamic acid group and 16.4% in the placebo group (relative risk, 0.87; 95% CI, 0.76-1.00; P = .053). Conclusions In this trial of patients having coronary artery surgery, tranexamic acid did not affect death or severe disability through to 1 year after surgery. Further work should be done to explore possible beneficial effects on late cardiovascular events.

The purpose of this study was to describe the relationship of visual acuity, tactile sensitivity, and mobility of the upper extremities to the performance of proficient breast self-examination (BSE) in women 65 and older. A convenience sample of 32 women, ages 66-89, met with the investigator to have their visual acuity, tactile sensitivity, and upper extremity mobility tested. Their ability to perform the visual, tactile, and upper extremity components of proficient BSE also was tested by using simulated breast models (SBMs). Thirty of the women had adequate visual acuity (or = 20/40 Snellen equivalent) but were unable to visually detect the abnormalities on the SBM. Thirty of the women had tactile sensitivity of 10 mm (1 cm) or better on the static two-point discrimination test of the second, third, and fourth digits of each hand. Yet, only 13 of these women were able to locate the 1 cm lump; only 12 were able to locate the 5 mm lumps; and none were able to locate the 3 mm lump. The subjects' ability to pass the upper extremity mobility component of proficient BSE was significantly related to their ability to pass the upper extremity range of motion criteria. Limitations and deficits, mostly of the hands and shoulders, were revealed. When teaching BSE to older women, nurses are responsible for assessing limitations and deficits in their ability to perform proficient BSE and, if necessary, for intervening with alternatives. The need for further research in this area is indicated to improve assessment and education of older women regarding the use of proficient BSE for early detection of breast cancer.