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Several studies indicate that norepinephrine (NE) may be more effective than dopamine for the treatment of septic shock. Nonetheless, many consider dopamine to be the pressor of choice for shock refractory to volume resuscitation. Owing to fear of excessive vasoconstriction, accentuated end-organ hypoperfusion, and the development of multiple organ dysfunction syndrome (MODS), it is contended that NE may be deleterious. We analyzed the duration of NE use and the variables that predict mortality in a consecutive cohort of 406 surgical intensive care unit patients treated with NE for shock. Study parameters included age, acute physiology and chronic health evaluation (APACHE) II and APACHE III scores, hospital (HLOS) and intensive care unit (ULOS) length of stay, maximal and daily multiple organ dysfunction (MOD) scores, MOD score minus cardiovascular points (MOD-CV), duration of NE infusion, and survival. The duration of NE infusion was stratified into six subsets (1, 2, 3-5, 6-10, 11-20, and > or =21 days). An age- and APACHE II and III score-matched cohort of 195 patients, in whom NE was not utilized, was identified retrospectively for comparison. The prevalence of NE use was 10.9%. NE patients developed MODS to a greater degree (11.7 +/- .3 vs. 5.9 +/- .4 points, p < .0001). NE patients had a greater degree (p < .0001) of noncardiovascular MOD as well. When stratified by survival, a greater degree of MOD occurred in both nonsurvivors and survivors of NE (both, p < .0001) compared with comparably ill patients without pressor-dependent shock. MOD scores, ULOS, and HLOS increased progressively with prolonged NE therapy (all, p < .0005), whereas mortality increased significantly only when the duration of NE infusion exceeded 10 days (p = .05). By multivariate analysis of variance (ANOVA), MOD score (p < .0001), and APACHE III (p < .01) predicted mortality, but notably the duration of NE therapy failed to attain predictive value (p = .3192). Only the MOD score was predictive of HLOS (p = .0001) and ULOS (p = .003). Daily MOD scores revealed that nonsurvivors of NE therapy were admitted to the intensive care unit with a greater degree of baseline organ dysfunction than NE survivors (7.5 +/- .4 vs. 5.1 +/- .2 for survivors, p < .0001). In addition, whereas survivors showed significant improvement by Day 5 (p < .01), MOD amongst nonsurvivors remained unchanged (p = .993). Although critically ill surgical patients requiring NE support have significantly greater degrees of organ dysfunction than patients not requiring pressors, much of the organ dysfunction is present on admission. The data contradict the notion that NE facilitates the development of MODS.

Purpose: Adverse outcomes apparently associated with hypothermia led us to examine patients undergoing elective abdominal aortic aneurysm (AAA) repairs to test the hypothesis that hypothermia (temperature less than 34.5 degrees C) is associated with increased morbidity and excess mortality rates., Methods: Two hundred sixty-two elective AAA repairs were retrospectively reviewed for preoperative and intraoperative risk factors. Core temperature, age, Acute Physiology and Chronic Health Evaluation (APACHE) II and APACHE III scores (raw and temperature-adjusted), fluid resuscitation, and perioperative organ dysfunction were recorded prospectively. Outcome measures included lengths of stay in the intensive care unit and in the hospital, and hospital mortality rates., Results: Except for a higher risk of hypothermia in women (p < 0.05), by univariate analysis, preoperative risk factors were similar in patients in the hypothermic and normothermic groups. After operation, patients with hypothermia had significantly greater APACHE scores (p < 0.0001), and patients in the hypothermic nonsurvivor group took significantly longer to rewarm (p < 0.05), suggesting marked hypoperfusion. Patients with hypothermia had significantly greater fluid (p < 0.05), transfusion (p < 0.01), vasopressor (p < 0.05), and inotrope (p < 0.05) requirements, resulting in significantly higher incidences of organ dysfunction (53.0% vs 28.7%, p < 0.01) and death (12.1% vs 1.5%, p < 0.01) and markedly prolonged lengths of stay in the unit (9.2 +/- 2.0 vs 5.3 +/- 0.6, p < 0.05) and in the hospital (24.3 +/- 2.9 vs 15.0 +/- 0.08, p < 0.01). By multivariate analysis, female gender (p = 0.004) was the only predictor of intraoperative hypothermia, whereas initial hypothermia was significantly predictive of both prolonged hypothermia and development of organ failure (p < 0.05). Organ failure (p < 0.05) and acute myocardial infarction (p < 0.01) were independent predictors of death., Conclusions: After AAA repair, patients with hypothermia have multiple physiologic derangements associated with adverse outcomes. Although multiple etiologic factors are interacting, body temperature is one variable that should be controlled during aortic surgery.