Methylprednisolone does not influence endotoxin translocation during cardiopulmonary bypass

This study investigated whether the prophylactic administration of methylprednisolone sodium succinate (MPSS) could prevent an increase in plasma endotoxin levels during cardiac surgery with cardiopulmonary bypass. MPSS (1 g/patient) or saline was given intravenously with induction in the steroid (n = 6) and control (n = 7) groups, respectively. Blood samples were collected preinduction and postinduction, during and after cardiopulmonary bypass, and 1 and 24 hours postoperatively. Plasma endotoxin was determined by a chromogenic Limulus amebocyte lysate assay. There was an intraoperative increase in the level of plasma endotoxin that occurred primarily after initiation of cardiopulmonary bypass and removal of the aortic cross-clamp. Endotoxin at 1 and 24 hours postoperatively was lower than the peak intraoperative levels and approached the preinduction level in both groups. The pump prime and other administered fluids contained low levels of endotoxin that were at or below the preinduction or postinduction level of the patients. MPSS did not prevent or attenuate the degree of endotoxemia during cardiopulmonary bypass. The loss of normal gut mucosal barrier function during cardiopulmonary bypass may result in endotoxemia and/or bacterial translocation, either of which could initiate or contribute to postoperative complications.