The anesthesia in abdominal aortic surgery (ABSENT) study: a prospective, randomized, controlled trial comparing troponin T release with fentanyl-sevoflurane and propofol-remifentanil anesthesia in major vascular surgery.

BACKGROUND: On the basis of data indicating that volatile anesthetics induce cardioprotection in cardiac surgery, current guidelines recommend volatile anesthetics for maintenance of general anesthesia during noncardiac surgery in hemodynamic stable patients at risk for perioperative myocardial ischemia. The aim of the current study was to compare increased troponin T (TnT) values in patients receiving sevoflurane-based anesthesia or total intravenous anesthesia in elective abdominal aortic surgery. METHODS: A prospective, randomized, open, parallel-group trial comparing sevoflurane-based anesthesia (group S) and total intravenous anesthesia (group T) with regard to cardioprotection in 193 patients scheduled for elective abdominal aortic surgery. Increased TnT level on the first postoperative day was the primary endpoint. Secondary endpoints were postoperative complications, nonfatal coronary events and mortality. RESULTS: On the first postoperative day increased TnT values (>13 ng/l) were found in 43 (44%) patients in group S versus 41 (43%) in group T (P = 0.999), with no significant differences in TnT levels between the groups at any time point. Although underpowered, the authors found no differences in postoperative complications, nonfatal coronary events or mortality between the groups. CONCLUSIONS: In elective abdominal aortic surgery sevoflurane-based anesthesia did not reduce myocardial injury, evaluated by TnT release, compared with total intravenous anesthesia. These data indicate that potential cardioprotective effects of volatile anesthetics found in cardiac surgery are less obvious in major vascular surgery.

Proinflammatory cytokines and complement activation in salvaged blood from abdominal aortic aneurism surgery and total hip replacement surgery.

BACKGROUND: Levels of proinflammatory mediators in unwashed salvaged blood from abdominal aortic aneurism (AAA) surgery are unknown. We hypothesized that there are higher levels of these mediators in unwashed blood salvaged in AAA surgery compared to hip replacement surgery. STUDY DESIGN AND METHODS: Ten patients scheduled for AAA surgery (Group A) and 10 patients for total hip replacement surgery (Group H) were included. Blood samples from the autotransfusion set were obtained during surgery and arterial samples before, during, and 6 hours after surgery. Determination of interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor-α, activated complement 3 (C3a), and high-sensitivity C-reactive protein (CRP) were performed. Salvaged blood was not retransfused. RESULTS: Levels (median [range]) of IL-8 in blood in the salvage system were higher in Group A versus Group H (215.3 [22.5-697.2] vs. 35.3 [16.7-66.6] pg/mL; p = 0.002). Higher levels of IL-6 were also seen in Group A versus Group H (60.0 [52.6-62.2] vs. 42.34 [19.4-62.2] pg/mL; p = 0.049). Levels of IL-6 in blood sampled during surgery were approximately fivefold higher in Group A versus Group H (p = 0.023), whereas approximately 70% higher levels of C3a were observed in Group H versus Group A (p = 0.021). Postoperative concentrations of IL-1ß (p = 0.002), IL-6 (p = 0.001), and IL-8 (0.005) were higher in Group A versus Group H. CONCLUSION: Salvaged blood in AAA surgery contains substantially higher levels of proinflammatory mediators compared to blood in total hip replacement surgery.

The "smoker's paradox" in patients with acute coronary syndrome: a systematic review.

BACKGROUND: Smokers have been shown to have lower mortality after acute coronary syndrome than non-smokers. This has been attributed to the younger age, lower co-morbidity, more aggressive treatment and lower risk profile of the smoker. Some studies, however, have used multivariate analyses to show a residual survival benefit for smokers; that is, the "smoker's paradox". The aim of this study was, therefore, to perform a systematic review of the literature and evidence surrounding the existence of the "smoker's paradox". METHODS: Relevant studies published by September 2010 were identified through literature searches using EMBASE (from 1980), MEDLINE (from 1963) and the Cochrane Central Register of Controlled Trials, with a combination of text words and subject headings used. English-language original articles were included if they presented data on hospitalised patients with defined acute coronary syndrome, reported at least in-hospital mortality, had a clear definition of smoking status (including ex-smokers), presented crude and adjusted mortality data with effect estimates, and had a study sample of > 100 smokers and > 100 non-smokers. Two investigators independently reviewed all titles and abstracts in order to identify potentially relevant articles, with any discrepancies resolved by repeated review and discussion. RESULTS: A total of 978 citations were identified, with 18 citations from 17 studies included thereafter. Six studies (one observational study, three registries and two randomised controlled trials on thrombolytic treatment) observed a "smoker's paradox". Between the 1980s and 1990s these studies enrolled patients with acute myocardial infarction (AMI) according to criteria similar to the World Health Organisation criteria from 1979. Among the remaining 11 studies not supporting the existence of the paradox, five studies represented patients undergoing contemporary management. CONCLUSION: The "smoker's paradox" was observed in some studies of AMI patients in the pre-thrombolytic and thrombolytic era, whereas no studies of a contemporary population with acute coronary syndrome have found evidence for such a paradox.

The effect of tobacco smoking and treatment strategy on the one-year mortality of patients with acute non-ST-segment elevation myocardial infarction.

BACKGROUND: The aim of the present study was to investigate whether a previously shown survival benefit resulting from routine early invasive management of unselected patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) may differ according to smoking status and age. METHODS: Post-hoc analysis of a prospective observational cohort study of consecutive patients admitted for NSTEMI in 2003 (conservative strategy cohort [CS]; n = 185) and 2006 (invasive strategy cohort [IS]; n = 200). A strategy for transfer to a high-volume invasive center and routine early invasive management was implemented in 2005. Patients were subdivided into current smokers and non-smokers (including ex-smokers) on admission. RESULTS: The one-year mortality rate of smokers was reduced from 37% in the CS to 6% in the IS (p < 0.001), and from 30% to 23% for non-smokers (p = 0.18). Non-smokers were considerably older than smokers (median age 80 vs. 63 years, p < 0.001). The percentage of smokers who underwent revascularization (angioplasty or coronary artery bypass grafting) within 7 days increased from 9% in the CS to 53% in the IS (p < 0.001). The corresponding numbers for non-smokers were 5% and 27% (p < 0.001). There was no interaction between strategy and age (p = 0.25), as opposed to a significant interaction between strategy and smoking status (p = 0.024). Current smoking was an independent predictor of one-year mortality (hazard ratio 2.61, 95% confidence interval 1.43-4.79, p = 0.002). CONCLUSIONS: The treatment effect of an early invasive strategy in unselected patients with NSTEMI was more pronounced among smokers than non-smokers. The benefit for smokers was not entirely explained by differences in baseline confounders, such as their younger age.

Effect of implementing routine early invasive strategy on one-year mortality in patients with acute myocardial infarction.

The aim of the present study was to investigate whether the implementation of an early invasive strategy for unselected patients with acute myocardial infarction (AMI) would be associated with reduced long-term mortality compared to a conservative approach. In this prospective observational cohort study of consecutive patients admitted for AMI in 2003 (conservative cohort, n = 311) and 2006 (invasive cohort [IC], n = 307), an 11% absolute and 41% relative reduction in 1-year mortality was found for patients with AMI in the IC compared to the conservative cohort (p = 0.001). These findings were consistent after adjustment for age, gender, previous AMI, previous stroke, diabetes, smoking status, previous left ventricular systolic dysfunction, and serum creatinine at admission (hazard ratio 0.54, 95% confidence interval 0.38 to 0.78) and Global Registry of Acute Coronary Events risk score (hazard ratio 0.67, 95% confidence interval 0.46 to 0.97). More patients with ST-segment elevation myocardial infarction received primary percutaneous coronary intervention in the IC (57% vs 3%, p <0.001), and a sixfold (25% vs 4%, p <0.001) increase in early percutaneous coronary intervention (<72 hours) for patients with non-ST-segment elevation myocardial infarction was observed. A greater proportion of patients in the IC received clopidogrel, aspirin, and statins during follow-up; otherwise, the secondary prevention measures were similar in the 2 cohorts. In conclusion, the introduction of a strategy for routine transfer to a high-volume percutaneous coronary intervention center for early invasive therapy was accompanied by a substantial reduction in mortality among unselected patients with AMI. Differences in unmeasured confounders might have accounted for a part of the difference in outcome.

[Referral to elective and emergency coronary investigation from a medium-size central hospital]. / Henvisning til elektiv og akutt koronarutredning fra et middels stort sentralsykehus.

BACKGROUND: Little is known about regional differences in the incidence of acute and elective invasive coronary procedures in Norway. Such information is important in the planning of new invasive centres. MATERIALS AND METHODS: In this prospective study all patients referred to coronary angiography at the Rikshospitalet University Hospital in Oslo (100 km remote) from the county of Vestfold (218,000 inhabitants) from 1 December 2002 to 30 November 2003 were included. Referrals were categorised as acute or elective. Based upon the discharge summaries from Oslo, all coronary angiographies, percutaneous interventions and coronary artery bypass grafts were registered. RESULTS: A total of 760 patients were referred, of whom 746 (98 %) underwent coronary angiography (19 % acutely). They were treated as follows: percutaneous coronary intervention, n = 295 (31 % acutely); coronary artery bypass grafting, n = 123 and conservative treatment, n = 342. INTERPRETATION: Based upon these results, the incidence figures for 100,000 inhabitants per year in 2003 were similar to the nation-wide average for percutaneous interventions per year in Norway in 2001 and approximately 30 % below that average for 2003. Therefore, in the planning of an optimal peripheral catheterisation laboratory, the population basis has to be calculated from the local incidence of procedures, since there are obviously significant regional differences in the use of such procedures.