Diastolic dysfunction as a predictor of weaning failure: A systematic review and meta-analysis.

PURPOSE: Weaning failure and prolonged mechanical ventilation are associated with increased morbidity, cost of care, and high mortality rates. In the last few years, cardiac performance has been recognized as a common etiology of weaning failure, and growing evidence suggests that left ventricular diastolic dysfunction is a key factor that determines weaning outcomes. Therefore, we performed a systematic review and a meta-analysis to evaluate whether diastolic dysfunction in the critically ill patient subjected to mechanical ventilation is an independent predictor of weaning failure. MATERIALS AND METHODS: We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, LILACS, Google Scholar, and ClinicalTrials.gov from inception to September 2014, along with conferences proceeding from January 2005 through September 2014, and included Observational Studies and Randomized Clinical Trials evaluating predictors of weaning failure. RESULTS: Ten studies were included in the systematic review; and 7, in the meta-analysis (6 observational studies and 1 randomized controlled trial). Patients who developed weaning failure had a higher E/e' ratio when compared with those who did not (mean difference, 2.65; 95% confidence interval, 0.52-4.79; P= .01); however, there was no difference in the E/A ratio (mean difference, 0.07; 95% confidence interval, -0.04 to 0.18; P= .22). Both the E/e' and E/A ratios were associated with weaning-induced pulmonary edema at the end of a spontaneous breathing trial. CONCLUSION: A higher E/e' ratio is significantly associated with weaning failure, although a high heterogeneity of diastolic dysfunction criteria and different clinical scenarios limit additional conclusions linking diastolic dysfunction with weaning failure.

Physicochemical evaluation of acid-base disorders after liver transplantation and the contribution from administered fluids.

OBJECTIVES: To analyze the mechanism of acid-base disorders in liver transplant recipients and to examine the relationship between these disorders and the fluids administered during surgery. METHODS: This prospective study in a university-affiliated hospital intensive care unit (ICU) included 52 patients admitted to the ICU from December 2009 to January 2011. We examined the contributions of inorganic ion differences, lactate, unmeasured anions, phosphate, and albumin to metabolic acidosis. In addition to laboratory variables, we collected demographic and clinical data. RESULTS: Metabolic acidosis (standard base excess ≤ -2.0 mmol/L) was identified in 37 (71.2%) patients during the immediate postoperative period. The inorganic ion difference was the main determinant of acidosis, accounting for -6.17 mEq/L of acidifying effect. The acidemia was attenuated mainly by the alkalinizing effect of albumin reduction, which contributed +6.03 mEq/L. There was an inverse proportional relationship between the quantity of saline solution used during surgery and the inorganic ion difference during the immediate postoperative period. CONCLUSIONS: Hyperchloremia is the primary contributor to metabolic acidosis in liver transplant recipients. Possibly the use of chloride-rich solutions increases the incidence of this disorder.

Distúrbios ácido-básicos em pacientes críticos: método de stewart / Acid-base disorders in critically ill patients: stewart theory

Distúrbios do equilíbrio ácido-básico são comuns nos pacientes críticos, estando em geral associados à maior morbimortalidade. Métodos que permitam entender a natureza destes distúrbios e auxiliar e consequentemente identificar atidudes que possam evitá-los e/ou corrigi-los são portanto extremamente importantes. A avaliação tradicional