Received the first dose of study drug 4612 (97.0) (96.7) Received the second dose of the study drug 4586 (96.4) (96.5) Received both doses of the study drug 4581 (96.3) (96.3) no. = number; % = percentage

Approximately 1 in 5 patients experienced MINS after vascular surgery. MINS was independently associated with 30-day mortality. The majority of patients with MINS were asymptomatic and would have gone undetected without routine postoperative troponin measurement.

IntroductionEmerging epidemiological data suggest that obstructive sleep apnoea (OSA) is common in the general surgical population. Unfortunately, the majority of these patients are unrecognised and untreated at the time of surgery. There is substantial biological rationale to indicate that patients with unrecognised OSA are at a higher risk of postoperative vascular events. However, the extent of this morbidity is currently unknown. We have initated the postoperative vascular complications in the unrecognised obstructive sleep apnoea (POSA) study to determine the associations between OSA, nocturnal hypoxia and major postoperative vascular events in 1200 moderate-to-high risk patients undergoing major non-cardiac surgery.Methods and analysisThe POSA study is an international prospective observational cohort study. Using a type 3 portable sleep monitoring device and ambulatory oximetry, we will quantify the severity of OSA. The primary outcome is a composite of vascular death, myocardial infarction; non-fatal cardiac arrest; stroke; pulmonary embolism; congestive heart failure and new arrhythmia within 30 days of surgery. As of November 2013, we have recruited over 700 patients from nine centres in six countries. The mean age is 68 years, the mean body mass index is 27 kg/m2 and 55% of patients are men. 27.9% of patients have known coronary artery disease, over 76% have diabetes. The majority of patients underwent orthopaedic surgery (28%) and colorectal resection (18.5%).Ethics and disseminationThe POSA study has received ethics approval from all study sites before patient recruitment. Informed consent will be obtained from all patients. The POSA study will determine the risk of unrecognised OSA in major non-cardiac surgery. We will publish these findings in peer-reviewed journals.Trial Registration:ClinicalTrials.gov Identifier: NCT01494181

Cardiac troponin T (cTnT), even at low concentrations, is a risk factor for 30-day mortality in patients undergoing noncardiac surgery, but it is uncertain whether that risk is generalizable to patients with poor kidney function. We, therefore, evaluated the relationship between cTnT concentration and kidney function on the outcome of 30-day mortality in a post hoc analysis of a prospective cohort study of patients undergoing noncardiac surgery. cTnT was measured for 3 days after surgery and considered abnormal if the peak was $0.02 ng/ml. Of the included 14,037 patients, 267 (1.9%) patients died within 30 days of surgery. The adjusted hazard ratios for death with an abnormal cTnT concentration were 4.37 (95% confidence intervals [95% CI], 3.21 to 6.22), 6.15 (95% CI, 2.95 to 140.9), 6.30 (95% CI, 3.12 to 21.23), 1.33 (95% CI, 0.56 to 4.85), and 1.46 (95% CI, 0.46 to 9.21) for eGFR$60, 45 to ,60, 30 to ,45, 15 to ,30, and ,15 ml/min per 1.73 m 2 or on dialysis, respectively. Compared with patients with eGFR$60 ml/min per 1.73 m 2 , the adjusted hazard ratio was significantly lower for patients with eGFR=15 to ,30 ml/min per 1.73 m 2 (interaction P value=0.02). Redefining abnormal cTnT concentration as $0.03 ng/ml or a change of $0.02 ng/ml did not alter results. Because the risk associated with postoperative cTnT levels may be different for patients with eGFR,30 ml/min per 1.73 m 2 , additional research is required to determine how to interpret perioperative cTnT values for patients with low kidney function.