THE ASSOCIATION BETWEEN HYPOTHERMIA AND ADVERSE OUTCOME FOLLOWING CARDIAC SURGERY

Abstract

Introduction: Maintenance of normothermia in non-cardiac surgery patients in the perioperative period is associated with a decreased incidence of early postoperative cardiac morbidity [1]. Although cardiac surgery patients (CSP) are rewarmed following hypothermic cardiopulmonary bypass (CPB) or maintained normothermic during CPB, patients may still arrive in the intensive care unit (ICU) with some degree of hypothermia [2]. We chose to evaluate the association of hypothermia upon ICU admission and adverse outcome following cardiac surgery. Methods: A retrospective database analysis of all CSP (N = 6940) operated between January 1995 and December 1996 was undertaken. We chose to examine CSP with core (bladder) temperatures (T) >or=to and < 36 degrees Celsius (C) upon admission to the ICU. Significant associations with adverse outcomes were compared between the two groups. N = 2138 CSP in T < 36 C and N = 4802 CSP in T >or=to 36C. The student's t-test, Fisher's exact test or Pearson Chi-square test were used to identify significant outcome differences as previously defined [3]. Results: (Table 1)Table 1Discussion: These results demonstrate that ICU admission hypothermia (T < 36C) may be associated with an increased incidence of adverse outcomes in the early postoperative period. ICU admission normothermia (>or=to 36 C) may be associated with a reduced incidence of adverse outcomes including reduced intubation time, ICU LOS, transfusions, major morbidities and mortality.