title: Postoperative antithrombin levels and outcome in cardiac operations.
abstract: OBJECTIVE
  During cardiac operations with cardiopulmonary bypass surgery, antithrombin is consumed and low levels of antithrombin activity are commonly observed at admission to the intensive care unit (ICU). This study investigates the association between antithrombin activity at admission to the ICU (ICU-antithrombin activity) and various outcome variables.
  
  
  METHODS
  The authors conducted a prospective, observational cohort study.
  
  
  METHODS
  The study was conducted at a university hospital.
  
  
  METHODS
  The study consisted of 647 consecutive patients who had undergone cardiac surgery with cardiopulmonary bypass.
  
  
  RESULTS
  ICU-antithrombin activity significantly (p < .001) decreased with respect to preoperative values. As seen with univariate analysis, low levels of ICU-antithrombin activity were significantly associated with higher blood loss, prolonged mechanical ventilation time and ICU stay, a higher incidence of allogeneic blood products use, surgical reexploration, low cardiac output syndrome, adverse neurologic events, thromboembolic events, renal dysfunction, and hospital mortality. When corrected for the other explanatory variables, low levels of ICU-antithrombin activity remained independently associated with a prolonged ICU stay (p = .003) and with a higher incidence of surgical reexploration (p = .023), adverse neurologic events (p = .001), and thromboembolic events (p = .036). An ICU-antithrombin activity value of <58% was found to be predictive of prolonged ICU stay, with a sensitivity of 67% and a specificity of 83%.
  
  
  CONCLUSIONS
  Low levels of ICU-antithrombin activity are associated with a poor outcome in cardiac surgery; ICU-antithrombin activity is predictive of prolonged ICU stay.
authors.affiliation: Department of Cardiothoracic Anesthesia and Intensive Care, Istituto Policlinico S. Donato, Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ranucci
authors.forename: Alessandro
authors.initials: A
authors.lastname: Frigiola
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Menicanti
authors.forename: Antonio
authors.initials: A
authors.lastname: Ditta
authors.forename: Alessandra
authors.initials: A
authors.lastname: Boncilli
authors.forename: Simonetta
authors.initials: S
authors.lastname: Brozzi
mesh_terms: D000991:Antithrombins / Q000032:analysis*; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002315:Cardiopulmonary Bypass; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology; D011184:Postoperative Period; D011379:Prognosis; D012086:Reoperation; D012307:Risk Factors; D013923:Thromboembolism / Q000209:etiology; D016896:Treatment Outcome
chemical_list: D000991:Antithrombins