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Background: The relative contributions of intraoperative and postoperative hypotension to perioperative morbidity remain unclear. We determined the association between hypotension and a composite of 30-day myocardial infarction and death over three periods: (1) intraoperative, (2) remaining day of surgery, and (3) during the initial four postoperative days., Methods: This was a substudy of POISE-2, a 10,010-patient factorial-randomized trial of aspirin and clonidine for prevention of myocardial infarction. Clinically important hypotension was defined as systolic blood pressure less than 90 mmHg requiring treatment. Minutes of hypotension was the exposure variable intraoperatively and for the remaining day of surgery, whereas hypotension status was treated as binary variable for postoperative days 1 to 4. We estimated the average relative effect of hypotension across components of the composite using a distinct effect generalized estimating model, adjusting for hypotension during earlier periods., Results: Among 9,765 patients, 42% experienced hypotension, 590 (6.0%) had an infarction, and 116 (1.2%) died within 30 days of surgery. Intraoperatively, the estimated average relative effect across myocardial infarction and mortality was 1.08 (98.3% CI, 1.03, 1.12; P < 0.001) per 10-min increase in hypotension duration. For the remaining day of surgery, the odds ratio was 1.03 (98.3% CI, 1.01, 1.05; P < 0.001) per 10-min increase in hypotension duration. The average relative effect odds ratio was 2.83 (98.3% CI, 1.26, 6.35; P = 0.002) in patients with hypotension during the subsequent four days of hospitalization., Conclusions: Clinically important hypotension-a potentially modifiable exposure-was significantly associated with a composite of myocardial infarction and death during each of three perioperative periods, even after adjustment for previous hypotension.

Background: Several studies have evaluated preoperative B-type natriuretic peptides (NPs) for predicting mortality after surgery; however, the number of deaths in each study was small, limiting the power of these studies. We conducted a systematic review and meta-analysis of studies addressing preoperative NP levels to predict mortality after cardiac and noncardiac surgery., Methods: We searched MEDLINE and EMBASE using the terms "natriuretic peptides," "surgery or surgical procedures," and a validated combination of prognostic and diagnostic terms. Two investigators independently assessed studies for eligibility and extracted data. The end points were all-cause mortality at ≥6 months and at ≤90 days. We used a bivariate model to derive measures of prognostic accuracy and their heterogeneity. We calculated the pooled positive predictive value (PPV) and negative predictive value (NPV) by Bayesian Markov chain Monte Carlo methods., Results: Of the 1558 retrieved articles, 23 studies satisfied the predefined eligibility criteria. After cardiac surgery, the diagnostic odds ratio of NP was 4.11 (95% confidence interval, 2.22-7.60) for ≥6-month mortality, the PPV 0.17 (95% Bayesian confidence interval, 0.07-0.36), and the NPV 0.96 (0.90-0.98). After noncardiac surgery, the diagnostic odds ratio of NP was 4.97 (3.06-8.07) for ≥6-month mortality. The corresponding PPV was 0.24 (0.14-0.38) and the NPV 0.94 (0.88-0.97). Results were similar for ≤90-day mortality., Conclusions: Preoperative NP concentrations were associated with mortality after cardiac and noncardiac surgery. NP had high NPVs for both types of surgery suggesting that preoperative NP concentrations may be helpful in preoperative risk stratification., (© 2011 International Anesthesia Research Society)

Background: Diabetes mellitus (DM), particularly if insulin-dependent, is a predictor of increased perioperative risk, whereas stringent metabolic control with insulin is beneficial in the critically ill., Methods: The impact of oral hypoglycemics (OH) vs. insulin on outcome was determined as a secondary retrospective analysis of a cohort study in patients with coronary artery disease (CAD) and DM undergoing major non-cardiac surgery. Primary end-point was 2-year all-cause mortality; secondary endpoints were perioperative myocardial ischemia and 2-year cardiac mortality., Results: Of 173 patients, DM was diagnosed in 42 (24%) based on pre-existing treatment with OH (15%) or insulin (9%). During follow-up, 40/173 (23%) patients died. All-cause mortality was similar in the non-diabetic (20%) and insulin groups (19%) but significantly higher in the OH group (42%; p = 0.025). Cardiac mortality tended to be higher in the OH group compared with the insulin and non-diabetic groups (27 vs. 19% and 11%, respectively; p = 0.066). Multivariate analysis revealed renal failure (odds ratio [OR] = 4.9, 95% confidence interval [CI] = 1.8-13.0), treatment with OH (OR = 3.3, 95% CI = 1.2-9.0), peripheral vascular surgery (OR = 2.7, 95% CI = 1.2-6.0), and prior diuretic therapy (OR = 2.6, 95% CI = 1.1-5.7) being independently associated with 2-year all-cause death. No difference existed in postoperative ischemia among the different groups., Conclusions: Long-term mortality after major non-cardiac surgery is elevated in patients with CAD and diabetes mellitus only if they are treated with OH, but not if they are treated with insulin. Further evaluation of the impact of perioperative anti-diabetic treatment on morbidity and mortality in CAD is warranted., (2007 S. Karger AG, Basel)

Background: Knowledge of the prognostic information of preoperative 12-lead electrocardiogram (ECG) recordings in patients with coronary artery disease (CAD) undergoing noncardiac surgery is limited., Methods: The prognostic information derived from the preoperative ECGs of 172 CAD patients undergoing major noncardiac surgery was analyzed to determine its predictive value for long-term outcome. Primary end point was all-cause mortality; secondary end point was major adverse cardiac events (MACE) at 2 years., Results: Prevalence of ECG abnormalities was 53% for T-wave alterations; 46% for Q waves; 38% for ST deviations; and, depending on the criterion used, 2% to 19% for left ventricular hypertrophy. During follow-up, 40 (23%) patients died and 31 (18%) had MACE. After adjustment for clinical baseline findings, including current medication with beta-blockers, ST depressions (odds ratio [OR] 4.5, 95% confidence interval [CI] 1.9-10.5) and faster heart rate (HR) (OR 1.6, 95% CI 1.1-2.4, per 10 beats per minute [bpm] increase) were independent predictors of all-cause mortality. Faster HR (OR 1.7, 95% CI 1.1-2.6, per 10-bpm increase) was also an independent predictor of MACE. The predictive value of ECG variables did not change after adjustment for occurence of perioperative ischemia., Conclusion: In CAD patients, the preoperative ECG contains important prognostic information and is predictive of long-term outcome independent of clinical findings and perioperative ischemia.

Objectives: The aim of this study was to determine whether perioperative measurements of heart rate variability (HRV) and cardiac troponin I (cTnI) add additional prognostic information to established risk scores for first-year mortality in patients at risk of coronary artery disease (CAD) undergoing major noncardiac surgery., Background: In cardiac-risk patients undergoing major noncardiac surgery, the short- and long-term prognoses are mainly influenced by perioperative cardiac complications. Heart rate variability and cTnI are important prognostic markers in patients with congestive heart failure and myocardial infarction., Methods: In a prospective study, 173 patients with CAD or at high risk of CAD undergoing major noncardiac surgery were followed up for one year. The main outcome measure was all-cause mortality. In addition to clinical parameters and established risk scores, HRV and cTnI were assessed perioperatively., Results: Twenty-eight (16%) patients died within one year. Multivariate logistic regression analysis revealed three findings that were independently associated with death within the first year after surgery: the revised cardiac risk index (odds ratio 6.2 [95% confidence interval 1.6 to 25], depressed HRV before induction of anesthesia (16.2 [2.8 to 94]), and elevation of cTnI on postoperative day 1 or 2 (9.8 [3.0 to 32])., Conclusions: Depressed HRV before induction of anesthesia and elevated cTnI postoperatively are independent and powerful predictors of one-year mortality for patients at risk of CAD undergoing major noncardiac surgery and add incremental prognostic information to established risk scores that only consider preoperative information.