Changes of lactate levels during cardiopulmonary bypass in patients undergoing cardiac transplantation: possible early marker of morbidity and mortality.

OBJECTIVES: High levels of lactate are associated with tissue hypoperfusion during cardiac surgery resulting in postoperative morbidity and mortality among patients undergoing cardiopulmonary bypass (CBP). Our goal was to evaluate the change in lactate levels during CBP for their possible predictive value for complications after heart transplant surgery. MATERIALS AND METHODS: From January to December 2010 we studied lactate levels in 16 heart transplant patients. Arterial blood samples were collected before, during, and after cardiopulmonary bypass on admission to the intensive care unit (ICU). Lactate levels were measured using the cobas B221 (Roche Diagnostic). The neurological, lung, and kidney complications were associated with mortality within 30 days. RESULTS: One patient displayed lactate levels > 2 mmol/L before bypass while 4 (25%) showed levels > 4 mmol/L during CPB. Lactate values higher than or equal to 4 mmol/L on ICU admission occurred in nine patients (56%). Postoperative mortality was higher among the group with levels above below 4 mmol/L on ICU admission (18.7% vs 6.2%). Neurological complications were observed in 22% of patients with elevated levels as opposed to none of the patients with levels below 4 mmol/L. Pulmonary complications were noted in 22% of patients with high lactate values versus 0% among the other group. CONCLUSION: Hyperlactemia above certain levels occurring during CPB serve as a biomarker to identify early postoperative morbidity and mortality.

¿Subdural o epidural? Dos posibles nuevos casos de punción subdural / Subdural or epidural? Two possible new cases of subdural perforation

Presentamos dos casos clínicos de posible bloqueo subdural accidental tras la identificación del espacio epidural para la administración de analgesia en gestante a término para trabajo de parto. En los casos que describimos, la localización del espacio epidural se realizó sin incidencias. Las pruebas de identificación fueron favorables. Fue en ambos casos que se apreció la salida de líquido cefalorraquídeo cuando se introdujo el catéter. Describimos la posibilidad de haber localizado "un espacio vacío" con la aguja de Tuhoy, que bien pudo ser el espacio subdural, pero fue el catéter el que perforó la membrana subaracnoidea. Planteamos la discusión en torno a cómo hubiéramos podido saber la posición de la aguja y así haber evitado la perforación subaracnoidea con el catéter. ¿Es lógico pensar, hoy día, que deben imponerse técnicas de localización del espacio epidural más sofisticadas? (AU)