title: The influence of heparin resistance on postoperative complications in patients undergoing coronary surgery.
abstract: BACKGROUND
  Heparin resistance is relatively frequent in patients undergoing coronary surgery. We aimed to assess the impact of heparin resistance on the outcome of patients undergoing coronary surgery with cardiopulmonary bypass (CABG). Three definitions of heparin resistance were adopted.
  
  
  METHODS
  We performed a retrospective review of 756 consecutive patients undergoing isolated CABG. All anaesthesia records were reviewed manually. Heparin resistance was recognized if: ACT was less than 400 seconds after 300 U/kg heparin (local criteria), ACT was less than 480 seconds after 400 U/kg or more heparin (stringent criteria), or if heparin sensitivity index was lower than 1.3. Postoperative assessment included perioperative morbidity and mortality. A multiple logistic regression model was used to investigate the influence of all demographic, preoperative and surgical variables, as well as heparin resistance (variably defined) on hospital mortality and postoperative complications.
  
  
  RESULTS
  Heparin sensitivity index, local criteria and stringent criteria identified 64.8%, 12.0% and 4.3% heparin resistant patients, respectively. Heparin-resistant patients more frequently had preoperative heparin administration, unstable course of coronary artery disease, and higher coronary symptoms scoring. Severe form of heparin resistance (expressed by the ACT less than 480 seconds after 400 U/kg heparin) was an independent predictor of death (OR 4.92; CI 1.11-21.89).
  
  
  CONCLUSIONS
  Mild forms of heparin resistance are relatively frequent and are not associated with increased morbidity and mortality. The isolation of severe heparin resistance as an independent predictor of death in our large cohort of coronary patients suggests that this phenomenon should be given more attention in future studies.
authors.affiliation: Silesian Centre for Heart Diseases, Zabrze, Poland. pknapik@sum.edu.pl
authors.forename: Piotr
authors.initials: P
authors.lastname: Knapik
authors.forename: Daniel
authors.initials: D
authors.lastname: Cieśla
authors.forename: Roman
authors.initials: R
authors.lastname: Przybylski
authors.forename: Tomasz
authors.initials: T
authors.lastname: Knapik
mesh_terms: D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000401:mortality; D003324:Coronary Artery Disease / Q000188:drug therapy / Q000401:mortality / Q000601:surgery; D006493:Heparin / Q000008:administration & dosage / Q000627:therapeutic use*; D017052:Hospital Mortality; D006801:Humans; D011183:Postoperative Complications / Q000209:etiology*; D012189:Retrospective Studies
chemical_list: D006493:Heparin