Effect of perioperative complications on excess mortality among women after coronary artery bypass: The israeli coronary artery bypass graft study (ISCAB)

AbstractBackground: Widely observed excess mortality among women after coronary artery bypass grafting is still largely unexplained, although case-mix factors have been identified. We evaluated the contribution of perioperative complications to the risk of 180-day mortality among women while adjusting for case-mix factors. Methods: This is part of a prospective, 1-year nationwide Israeli coronary artery bypass graft study of 1029 female and 3806 male patients. Deaths within 180 days were independently ascertained. Case-mix risk strata were obtained from a pooled Cox survival model (including all subjects and study variables) by using the adjusted coefficients corresponding to the case-mix factors within the model. Sex-specific mortality associated with perioperative complications was evaluated within the strata. In addition, sex-specific Cox models were constructed. Results: Higher mortality among women compared with that among men was significant within the pooled model (hazard ratio, 1.4; P =.038) and was evident early in the postoperative period. Women tended to cluster in the highest risk quartile compared with men (39.8% vs 20.9%, P <.001). However, although the incidence of perioperative complications was similar for the 2 sexes, the associated mortality for a given perioperative complication was higher among women. Sex-specific Cox models confirmed the above findings. For example, the hazard ratio for women with low postoperative hemoglobin was 6.9, whereas for men, the hazard ratio was 3.9. Conclusions: The role of perioperative factors in the excess mortality among women after coronary artery bypass grafting shifts the focus of attention from the selection of women for the operation to the in-hospital experience. Improving the outcome for women will entail efforts to prevent complications in the perioperative period.J Thorac Cardiovasc Surg 2002;123:517-2

Effect of infections on 30-day mortality among critically ill patients hospitalized in and out of the intensive care unit

Background: This analysis is part of a multicenter study conducted in Israel to evaluate survival of critically ill patients treated in and out of intensive care units (ICUs). Objective: To assess the role of infection on 30-day survival among critically ill patients hospitalized in ICUs and regular wards. Design: All adult inpatients were screened on four rounds for patients meeting ICU admission criteria. Retrospective chart review was used to detect presence and type of infection. Mortality was ascertained from day of meeting study criteria to 30 days thereafter. Analysis: The effect of infection on mortality among patients, treated in and out of the ICU, was compared using Kaplan Meier survival curves. Multivariate Cox models were constructed to adjust interdepartmental comparisons for case-mix differences. Results: Of 641 critically ill patients identified, 36.8% already had an infection on day 0. An additional 40.2% subsequently developed a new infection during the follow-up period, ranging from 64.6% in the ICU to 31.5% in regular wards (p < .001). Resistant infections were more prevalent in ICUs. Infection was independently associated with an increase in mortality, regardless of whether the patient was admitted to the ICU. There was no difference in the adjusted risk of mortality associated with an infection diagnosed on day 0 vs. an infection diagnosed later. Risk of dying was similar in resistant and nonresistant infections. Adjusting for infections, survival of ICU patients was better relative to patients in regular wards (adjusted hazard ratio = 0.7). Among the different types of infection, risk of mortality from pneumonia was significantly lower in ICUs relative to regular wards. There was a protective effect in ICUs among noninfected patients. Conclusion: The risk of acquiring a new infection is greater in the ICU. However, risk of mortality among ICU patients was lower for the most serious infections and for those without any infection