Blood levels of atrial natriuretic peptide, endothelin, cortisol and ACTH in patients undergoing coronary artery bypass grafting surgery with cardiopulmonary bypass

Previous studies demonstrated a biphasic time course with post-operative di ssociation of blood levels of cortisol and ACTH in patients undergoing majo r surgery and critically ill patients. A possible role of endothelin and at rial natriuretic peptide (ANP) in the dissociation of concentrations of cor tisol and ACTH in critically ill patients has been suggested. In the presen t study, we investigated the perioperative course of blood levels of endoth elin, ANP, ACTH, and cortisol in 13 male patients undergoing cardiac surger y with cardiopulmonary bypass (CPB): group 1 consisted of 7 patients with a n uneventful perioperative period and group 2 consisted of 6 patients with perioperative complications. Blood samples were taken pre-[T1], intra-[T2], post-operatively (on the day of surgery) [T3], as well as on the first [T4 ] and second [T5] post-operative days. Blood samples of endothelin, ANP, co rtisol, and ACTH were measured using commercially available immunoassays. P erioperatively, a biphasic time course with post-operative dissociation of ACTH and cortisol concentrations was observed in all patients studied. Intr aoperatively, during CPB, the highest levels of endothelin were found. Peri operatively, ANP and endothelin levels were elevated compared to pre-operat ive values up to the second post-operative day. On the second post-operativ e day, ANP concentrations were significantly higher in patients with compli cations in the perioperative period compared to those with an uneventful pe rioperative period. Our results suggest that: 1) plasma levels of ANP incre ased in patients with perioperative complications; 2) plasma levels of ANP may have prognostic value for patients undergoing cardiac surgery; and 3) t he dissociation of ACTH and cortisol cannot solely be explained by the incr ease in endothelin-1 and ANP concentrations observed in patients undergoing major surgery. (C) 2001, Editrice Kurtis.