Epidemiology, risk factors and outcomes of norepinephrine use in cardiac surgery with cardiopulmonary bypass: a multicentric prospective study

Background: The present study was designed to describe the prevalence of norepinephrine use, the factors associated with its use, and the incidence of postoperative complications according to norepinephrine use, in patients undergoing cardiac surgery with cardiopulmonary bypass. Method: We performed a prospective, multicenter, observational study in 4 University-affiliated medico-surgical cardiovascular units. We analyzed all patients treated with cardiac surgery after excluding pre-ECMO surgery, LVAD implantation, heart transplantation and intra-operative hemorrhage. Results: Of 9316 patients screened during the study period, 2862 were included and 2510 were analyzed. Among them, 1549 (61%) were treated with norepinephrine with a median maximal dose of 0.11 [0.06-0.2] µg. kg-1. min-1 and a median duration of 10 hours 2-24. Norepinephrine was most often started in the operating room before cardiopulmonary bypass. The multiple regression logistic analysis identified several modifiable (haematocrit, maintenance of beta-blocker, cardiopulmonary bypass time, glucose-insulin-potassium, Custodiol cardioplegia, Delnido cardioplegia, and fibrinogen transfusion) and non-modifiable factors (age, ASA score, chronic high blood pressure, coronary disease, dyslipidemia, right ventricular dysfunction, left ventricular dysfunction, active endocarditis, and valvular aortic surgery) associated with norepinephrine use. Mortality, morbidity (neurological and renal complications, death) and length of stay in the ICU were higher in patients treated with norepinephrine. Conclusion: Norepinephrine is often used in cardiac surgical patients but for less than 24 hours with a low dose. Many preoperative and surgical factors are associated with norepinephrine use. Patients supported by norepinephrine have a higher incidence of major postoperative events.