The relative merits of using a high-sensitivity cardiac Troponin T assay compared to a nonhigh-sensitivity troponin T assay after noncardiac surgery.

INTRODUCTION: Troponin elevation after noncardiac surgery is associated with an elevated risk of 30-day mortality. Little is known about relative merit of using a high-sensitivity Troponin T (hsTnT), the fifth-generation assay, vs the nonhigh sensitivity Troponin T (non-hsTnT), the fourth-generation assay, in the noncardiac surgery setting. We aimed to identify whether hsTnT can identify additional patients at risk that would have gone undetected with non-hsTnT measurement. METHODS: The VISION Study included 40,004 noncardiac surgery patients with postoperative troponin measurements. Among them, 1,806 patients had both fourth-generation non-hsTnT and fifth-generation hsTnT concomitant measurements (4,451 paired results). We compared the absolute concentrations, the timing, and the impact of different thresholds on predicting 30-day major cardiovascular complications (composite of death, nonfatal cardiac arrest, coronary revascularization, and congestive heart failure). RESULTS: Based on the manufacturers' threshold of 14 ng/L, 580 (32.1%) patients had postoperative hsTnT concentrations greater than the threshold, while their non-hsTnT concentrations were below the manufacturer's threshold. These 580 patients had higher risk of major cardiovascular events (OR 2.33; CI 95% 1.04-5.23; P = .049) than patients with hsTnT concentrations below the manufacturer threshold. Among patients with myocardial injury after noncardiac surgery, only 50% would be detected by the fourth-generation non-hsTnT assay at 6 to 12 hours postoperative as compared to 85% with the fifth-generation hsTnT assay (P-value < .001). CONCLUSIONS: Within the first 3 postoperative days, fifth-generation hsTnT identified at least 1 in 3 patients with troponin elevation that would have gone undetected by fourth-generation non-hsTnT using published thresholds in this setting. Furthermore, fifth-generation hsTnT identified patients with an elevation earlier than fourth-generation non-hsTnT, indicating potential to improve postoperative risk stratification.

Preoperative levels of natriuretic peptides and the incidence of postoperative atrial fibrillation after noncardiac surgery: a prospective cohort study.

BACKGROUND: Postoperative atrial fibrillation (POAF) is associated with clinically significant short- and long-term complications after noncardiac surgery. Our aim was to describe the incidence of clinically important POAF after noncardiac surgery and establish the prognostic value of N-terminal pro-brain-type natriuretic peptide (NT-proBNP) in this context. METHODS: The Vascular events In noncardiac Surgery patIents cOhort evaluatioN (VISION) Study was a prospective cohort study involving patients aged 45 years and older who had inpatient noncardiac surgery that was performed between August 2007 and November 2013. We determined 30-day incidence of clinically important POAF (i.e., resulting in angina, congestive heart failure, symptomatic hypotension or requiring treatment) using logistic regression models to analyze the association between preoperative NT-proBNP and POAF. RESULTS: In 37 664 patients with no history of atrial fibrillation, we found that the incidence of POAF was 1.0% (95% confidence interval [CI] 0.9%-1.1%; 369 events); 3.2% (95% CI 2.3%-4.4%) in patients undergoing major thoracic surgery, 1.3% (95% CI 1.2%-1.5%) in patients undergoing major nonthoracic surgery and 0.2% (95% CI 0.1%-0.3%) in patients undergoing low-risk surgery. In a subgroup of 9789 patients with preoperative NT-proBNP measurements, the biomarker improved the prediction of POAF risk over conventional prognostic factors (likelihood ratio test p < 0.001; fraction of new information from NT-proBNP was 16%). Compared with a reference NT-proBNP measurement set at 100 ng/L, adjusted odds ratios for the occurrence of POAF were 1.31 (95% CI 1.15-1.49) at 200 ng/L, 2.07 (95% CI 1.27-3.36) at 1500 ng/L and 2.39 (95% CI 1.26-4.51) at 3000 ng/L. INTERPRETATION: We determined that the incidence of clinically important POAF after noncardiac surgery was 1.0%. We also found that preoperative NT-proBNP levels were associated with POAF independent of established prognostic factors. Trial registration: ClinicalTrials.gov, no. NCT00512109.

Association between complications and death within 30 days after noncardiac surgery.

BACKGROUND: Among adults undergoing contemporary noncardiac surgery, little is known about the frequency and timing of death and the associations between perioperative complications and mortality. We aimed to establish the frequency and timing of death and its association with perioperative complications. METHODS: We conducted a prospective cohort study of patients aged 45 years and older who underwent inpatient noncardiac surgery at 28 centres in 14 countries. We monitored patients for complications until 30 days after surgery and determined the relation between these complications and 30-day mortality using a Cox proportional hazards model. RESULTS: We included 40 004 patients. Of those, 715 patients (1.8%) died within 30 days of surgery. Five deaths (0.7%) occurred in the operating room, 500 deaths (69.9%) occurred after surgery during the index admission to hospital and 210 deaths (29.4%) occurred after discharge from the hospital. Eight complications were independently associated with 30-day mortality. The 3 complications with the largest attributable fractions (AF; i.e., potential proportion of deaths attributable to these complications) were major bleeding (6238 patients, 15.6%; adjusted hazard ratio [HR] 2.6, 95% confidence interval [CI] 2.2-3.1; AF 17.0%); myocardial injury after noncardiac surgery [MINS] (5191 patients, 13.0%; adjusted HR 2.2, 95% CI 1.9-2.6; AF 15.9%); and sepsis (1783 patients, 4.5%; adjusted HR 5.6, 95% CI 4.6-6.8; AF 12.0%). INTERPRETATION: Among adults undergoing noncardiac surgery, 99.3% of deaths occurred after the procedure and 44.9% of deaths were associated with 3 complications: major bleeding, MINS and sepsis. Given these findings, focusing on the prevention, early identification and management of these 3 complications holds promise for reducing perioperative mortality. Study registration: ClinicalTrials.gov, no. NCT00512109.

Stepped wedge cluster randomised controlled trial to assess the effectiveness of an optimisation strategy for general anaesthesia on postoperative morbidity and mortality in elderly patients (the OPTI-AGED study): a study protocol.

INTRODUCTION: Elderly patients constitute an increasingly large proportion of the high-risk surgical group. In adult patients, several specific intraoperative approaches such as cardiac output-guided haemodynamic therapy, depth of anaesthesia monitoring (DAM) or lung-protective ventilation (LPV) are designed to reduce postoperative mortality and surgical complications. However, none of these approaches has been specifically performed in the elderly, and no evaluation of a multimodal optimisation strategy for general anaesthesia has been achieved in this population. AIMS: The objective of this study is to assess, in high-risk patients aged 75 years and over undergoing high-risk surgery, the effectiveness of combined optimisation of anaesthesia involving goal-directed haemodynamic therapy (GDHT), LPV and electroencephalographic DAM on postoperative morbidity and mortality. The primary outcome of the study is a composite criterion associating major postoperative complications and mortality occurring within the 30 first postoperative days. The secondary outcomes are 1-year postoperative autonomy and mortality. METHODS AND ANALYSIS: This prospective, randomised, controlled, multicentre trial using a stepped wedge cluster design will be conducted in 27 French university centres. Patients aged 75 years and over, undergoing femoral head fractures and major intraperitoneal or vascular elective surgeries will be included after informed consent. They will benefit from usual care in the 'control group' and from a combined optimisation of general anaesthesia involving GDHT, LPV and DAM in the 'optimisation group'. The cluster's crossover will be unidirectional, from control to optimisation, and randomised. Data will be recorded at inclusion, the day of surgery, 7 days, 30 days and 1year postoperatively and collected into a hosted electronic case report form. The primary outcome of the study is a composite criterion associating major postoperative complications and mortality occurring within the 30 first postoperative days. The secondary outcomes are 1- year postoperative autonomy and mortality. ETHICS AND DISSEMINATION: This protocol was approved by the ethics committee Sud-Est 1 and the French regulatory agency. The finding of the trial will be disseminated through peer-reviewed journals and conferences TRIAL REGISTRATION NUMBER: NCT02668250; Pre-results.

Preoperative antihypertensive medication intake and acute kidney injury after major vascular surgery.

OBJECTIVE: Postoperative acute kidney injury (AKI) is frequent after major vascular surgery and is associated with significant morbidity and mortality. It remains unclear whether the administration of combined oral antihypertensive medications on the day of surgery can increase the risk of postoperative AKI. METHODS: We performed a retrospective cohort study of hypertensive patients undergoing elective major vascular surgery to determine the association between the number of antihypertensive medications continued on the morning of surgery and AKI at 48 hours postoperatively. RESULTS: A total of 406 patients who had undergone suprainguinal vascular surgery were included, and 10.3% suffered postoperative AKI. In multivariable analysis, the number of antihypertensive medications taken on the morning of surgery was independently associated with AKI (P = .026). Compared with patients who took no medication, taking one medication (adjusted odds ratio [aOR], 1.58; 95% confidence interval [CI], 0.68-3.75) and taking two or more medications (aOR, 2.70; 95% CI, 1.13-6.44) were associated with a 1.6-fold and 2.7-fold increased risk of postoperative AKI, respectively. Other predictors of AKI were suprarenal surgery (aOR, 3.37; 95% CI, 1.53-7.44), age (aOR, 2.29 per 10 years; 95% CI, 1.40-3.74), length of surgery (aOR, 1.40 per 1 hour; 95% CI, 1.10-1.76), hemoglobin drop (aOR, 1.37 per 10 g/L; 95% CI, 1.10-1.74), and history of coronary artery disease (aOR, 2.33; 95% CI, 1.08-5.00). CONCLUSIONS: In patients undergoing major vascular surgery who are treated with chronic antihypertensive therapy, the administration of antihypertensive drugs on the morning of surgery is independently associated with an increased risk of postoperative AKI. Further prospective studies are needed to confirm this finding.

Benzodiazepine administration during adult cardiac surgery: a survey of current practice among Canadian anesthesiologists working in academic centres.

BACKGROUND: Benzodiazepines are commonly administered during cardiac surgery because of their limited effect on hemodynamics and presumed role in preventing intraoperative awareness. Recent concerns about an increased risk of delirium with benzodiazepines have resulted in decreased usage in the intensive care unit and in geriatric perioperative practice. Little is known, however, about current benzodiazepine usage in the setting of adult cardiac surgery. METHODS: We contacted all academic anesthesia departments in Canada to identify practicing attending cardiac anesthesiologists; this group constituted our sampling frame. Information regarding participant demographics, benzodiazepine usage, type, dose, and other administration details were obtained by electronic survey. Responses were analyzed descriptively. RESULTS: The survey was completed by 243/346 (70%) of cardiac anesthesiologists. Eleven percent of respondents do not administer benzodiazepines. Midazolam was the most commonly used benzodiazepine, with a mean (standard deviation) dose of 4.9 (3.8) mg given to an average patient. When respondents were asked the proportion of patients that they gave benzodiazepines, the response was bimodal. The most common considerations that influenced benzodiazepine use were patient age (73%), patient anxiety (63%), history of alcohol/drug/benzodiazepine use (60%), and the presence of risk factors for intraoperative awareness (44%). CONCLUSIONS: Benzodiazepine use is common among academic cardiac anesthesiologists in Canada. Nonetheless, heterogeneity exists between individual practices, suggesting clinical equipoise between restrictive and liberal administration of benzodiazepines for cardiac anesthesia. L'administration de benzodiazépines pendant la chirurgie cardiaque chez l'adulte: évaluation de la pratique actuelle des anesthésiologistes canadiens exerçant en milieu universitaire.

Association of Postoperative High-Sensitivity Troponin Levels With Myocardial Injury and 30-Day Mortality Among Patients Undergoing Noncardiac Surgery.

IMPORTANCE: Little is known about the relationship between perioperative high-sensitivity troponin T (hsTnT) measurements and 30-day mortality and myocardial injury after noncardiac surgery (MINS). OBJECTIVE: To determine the association between perioperative hsTnT measurements and 30-day mortality and potential diagnostic criteria for MINS (ie, myocardial injury due to ischemia associated with 30-day mortality). DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of patients aged 45 years or older who underwent inpatient noncardiac surgery and had a postoperative hsTnT measurement. Starting in October 2008, participants were recruited at 23 centers in 13 countries; follow-up finished in December 2013. EXPOSURES: Patients had hsTnT measurements 6 to 12 hours after surgery and daily for 3 days; 40.4% had a preoperative hsTnT measurement. MAIN OUTCOMES AND MEASURES: A modified Mazumdar approach (an iterative process) was used to determine if there were hsTnT thresholds associated with risk of death and had an adjusted hazard ratio (HR) of 3.0 or higher and a risk of 30-day mortality of 3% or higher. To determine potential diagnostic criteria for MINS, regression analyses ascertained if postoperative hsTnT elevations required an ischemic feature (eg, ischemic symptom or electrocardiography finding) to be associated with 30-day mortality. RESULTS: Among 21 842 participants, the mean age was 63.1 (SD, 10.7) years and 49.1% were female. Death within 30 days after surgery occurred in 266 patients (1.2%; 95% CI, 1.1%-1.4%). Multivariable analysis demonstrated that compared with the reference group (peak hsTnT <5 ng/L), peak postoperative hsTnT levels of 20 to less than 65 ng/L, 65 to less than 1000 ng/L, and 1000 ng/L or higher had 30-day mortality rates of 3.0% (123/4049; 95% CI, 2.6%-3.6%), 9.1% (102/1118; 95% CI, 7.6%-11.0%), and 29.6% (16/54; 95% CI, 19.1%-42.8%), with corresponding adjusted HRs of 23.63 (95% CI, 10.32-54.09), 70.34 (95% CI, 30.60-161.71), and 227.01 (95% CI, 87.35-589.92), respectively. An absolute hsTnT change of 5 ng/L or higher was associated with an increased risk of 30-day mortality (adjusted HR, 4.69; 95% CI, 3.52-6.25). An elevated postoperative hsTnT (ie, 20 to <65 ng/L with an absolute change ≥5 ng/L or hsTnT ≥65 ng/L) without an ischemic feature was associated with 30-day mortality (adjusted HR, 3.20; 95% CI, 2.37-4.32). Among the 3904 patients (17.9%; 95% CI, 17.4%-18.4%) with MINS, 3633 (93.1%; 95% CI, 92.2%-93.8%) did not experience an ischemic symptom. CONCLUSIONS AND RELEVANCE: Among patients undergoing noncardiac surgery, peak postoperative hsTnT during the first 3 days after surgery was significantly associated with 30-day mortality. Elevated postoperative hsTnT without an ischemic feature was also associated with 30-day mortality.

Predictors of intraoperative testing in adults undergoing noncardiac surgery within a regional hospital system.

BACKGROUND: The use of intraoperative testing is central to anesthesia practice, and point-of-care testing (POCT) is often used. Nevertheless, POCT is costly and its contribution to patient outcome is unknown. There is a lack of guidelines to describe which patients should undergo intraoperative testing or how results should be applied. As such, we undertook a historical cohort study evaluating intraoperative testing practices within our region where POCT is not used. METHODS: In 2012, we obtained a random sample of 1,000 adult patients undergoing noncardiac surgery in three of our health system hospitals. Patient, surgical, and testing details were extracted, and the surgical procedures were categorized using the Johns Hopkins risk guidelines. Our primary outcome was the administration of at least one intraoperative test. We used a multivariable logistic regression model to identify factors associated with testing and described the time from ordering the tests to receiving the results using descriptive statistics. RESULTS: Study results showed that 110/1,000 (11.0%) patients underwent 413 diagnostic tests. Complete blood count was the most commonly administered test (36.3%), and the mean (standard deviation) time to obtain all test results was 29.9 (19.9) min. High-risk procedures were associated with an odds ratio (OR) of 12.3 (95% confidence interval [CI], 8.3 to 18.2; P < 0.001). Other predictors of intraoperative testing included emergency surgery (OR, 3.8; 95% CI, 2.0 to 7.2; P < 0.001), number of comorbidities (OR, 1.1; 95% CI, 1.0 to 1.2; P = 0.03), and duration of surgery (OR, 2.3; 95% CI, 1.8 to 2.9; P < 0.001). CONCLUSION: Intraoperative testing is common and more likely in patients undergoing high-risk surgical procedures. In a central laboratory system, there is substantial time from ordering the tests to receiving the results. The clinical impact of this delay is unknown. Further evaluation is required regarding the relationship between the time required for intraoperative test results and perioperative outcomes.

Myocardial injury after noncardiac surgery: a large, international, prospective cohort study establishing diagnostic criteria, characteristics, predictors, and 30-day outcomes.

BACKGROUND: Myocardial injury after noncardiac surgery (MINS) was defined as prognostically relevant myocardial injury due to ischemia that occurs during or within 30 days after noncardiac surgery. The study's four objectives were to determine the diagnostic criteria, characteristics, predictors, and 30-day outcomes of MINS. METHODS: In this international, prospective cohort study of 15,065 patients aged 45 yr or older who underwent in-patient noncardiac surgery, troponin T was measured during the first 3 postoperative days. Patients with a troponin T level of 0.04 ng/ml or greater (elevated "abnormal" laboratory threshold) were assessed for ischemic features (i.e., ischemic symptoms and electrocardiography findings). Patients adjudicated as having a nonischemic troponin elevation (e.g., sepsis) were excluded. To establish diagnostic criteria for MINS, the authors used Cox regression analyses in which the dependent variable was 30-day mortality (260 deaths) and independent variables included preoperative variables, perioperative complications, and potential MINS diagnostic criteria. RESULTS: An elevated troponin after noncardiac surgery, irrespective of the presence of an ischemic feature, independently predicted 30-day mortality. Therefore, the authors' diagnostic criterion for MINS was a peak troponin T level of 0.03 ng/ml or greater judged due to myocardial ischemia. MINS was an independent predictor of 30-day mortality (adjusted hazard ratio, 3.87; 95% CI, 2.96-5.08) and had the highest population-attributable risk (34.0%, 95% CI, 26.6-41.5) of the perioperative complications. Twelve hundred patients (8.0%) suffered MINS, and 58.2% of these patients would not have fulfilled the universal definition of myocardial infarction. Only 15.8% of patients with MINS experienced an ischemic symptom. CONCLUSION: Among adults undergoing noncardiac surgery, MINS is common and associated with substantial mortality.