Central venous saturation is a predictor of reintubation in difficult-to-wean patients.

OBJECTIVE: To evaluate the predictive value of central venous saturation to detect extubation failure in difficult-to-wean patients. DESIGN: Cohort, multicentric, clinical study. SETTING: Three medical-surgical intensive care units. PATIENTS: All difficult-to-wean patients (defined as failure to tolerate the first 2-hr T-tube trial), mechanically ventilated for >48 hrs, were extubated after undergoing a two-step weaning protocol (measurements of predictors followed by a T-tube trial). Extubation failure was defined as the need of reintubation within 48 hrs. INTERVENTIONS: The weaning protocol evaluated hemodynamic and ventilation parameters, and arterial and venous gases during mechanical ventilation (immediately before T-tube trial), and at the 30th min of spontaneous breathing trial. MEASUREMENTS AND MAIN RESULTS: Seventy-three patients were enrolled in the study over a 6-mo period. Reintubation rate was 42.5%. Analysis by logistic regression revealed that central venous saturation was the only variable able to discriminate outcome of extubation. Reduction of central venous saturation by >4.5% was an independent predictor of reintubation, with odds ratio of 49.4 (95% confidence interval 12.1-201.5), a sensitivity of 88%, and a specificity of 95%. Reduction of central venous saturation during spontaneous breathing trial was associated with extubation failure and could reflect the increase of respiratory muscles oxygen consumption. CONCLUSIONS: Central venous saturation was an early and independent predictor of extubation failure and may be a valuable accurate parameter to be included in weaning protocols of difficult-to-wean patients.

Final results of MRC CRASH, a randomised placebo-controlled trial of intravenous corticosteroid in adults with head injury-outcomes at 6 months.

MRC CRASH is a randomised controlled trial (ISRCTN74459797) of the effect of corticosteroids on death and disability after head injury. We randomly allocated 10,008 adults with head injury and a Glasgow Coma Scale score of 14 or less, within 8 h of injury, to a 48-h infusion of corticosteroid (methylprednisolone) or placebo. Data at 6 months were obtained for 9673 (96.7%) patients. The risk of death was higher in the corticosteroid group than in the placebo group (1248 [25.7%] vs 1075 [22.3%] deaths; relative risk 1.15, 95% CI 1.07-1.24; p=0.0001), as was the risk of death or severe disability (1828 [38.1%] vs 1728 [36.3%] dead or severely disabled; 1.05, 0.99-1.10; p=0.079). There was no evidence that the effect of corticosteroids differed by injury severity or time since injury. These results lend support to our earlier conclusion that corticosteroids should not be used routinely in the treatment of head injury.

Interaçäo coraçäo-pulmäo em pacientes críticos: aplicaçäo da ventilação mecânica como terapêutica não farmacológica na disfunçäo ventricular / Mechanical ventilation in patients with acute respiratory failure

A ventilação mecânica constitui o método usual de suporte para pacientes com insuficiência respiratória aguda. Sua utilização como terapêtica não farmacológica em pacientes com disfunção sistólica ventricular esquerda tem sido recentemente empregada. Observa-se que tanto a ventilação mecânica invasiva, com uso de pressão expiratória final positiva, quanto a ventilação mecânica não-invasiva, com uso de pressão positiva continua, modificam a pressão intratorácica, afetando e modificando os gradientes de pressão sobre as câmaras atriais, ventriculares e raiz da aorta. Estes efeitos resultam em alterações hemodinâmicas que contribuem para a melhora dos sintomas em pacientes com insuficiência cardíaca