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Published on: October 12, 2012

A statistical analysis of factors predisposing patients to heparin resistance

Tanee Chan1, Nian Chih Hwang, Chong Hee Lim

  • 1Department of Cardiothoracic Surgery, Perfusion Service, National Heart Centre, Singapore. perfusionist@nhc.com

Perfusion
|April 18, 2006
PubMed

Insights

Heparin resistance (HR) in cardiac surgery is linked to preoperative heparin use, higher platelet counts, and lower albumin levels. These factors predict the need for increased heparin dosage during cardiopulmonary bypass.

Area of Science:

  • Cardiology
  • Anesthesiology
  • Pharmacology

Background:

  • Heparin resistance (HR) can complicate cardiac surgery requiring cardiopulmonary bypass (CPB).
  • Identifying predictors of HR is crucial for optimizing anticoagulation management and patient safety.

Purpose of the Study:

  • To investigate potential factors predisposing patients to heparin resistance during cardiac surgery.
  • To identify clinical and laboratory predictors of HR in patients undergoing CPB.

Main Methods:

  • A prospective study of 400 patients undergoing elective cardiac surgery with CPB.
  • Data collected included demographics, preoperative therapies, laboratory results, and baseline activated clotting time (ACT).
  • Heparin resistance defined as requiring ≥5 mg/kg heparin to achieve ACT >400 seconds; analyzed using univariate and multivariate logistic regression.

Main Results:

  • 8.0% of patients (32/400) exhibited heparin resistance.
  • Preoperative heparin, low molecular weight heparin, platelet count ≥300,000/ml, and albumin <35 g/dl were significantly associated with HR (p<0.05).
  • HR patients required more volume replacement prior to CPB (p=0.007).

Conclusions:

  • Preoperative anticoagulant use, thrombocytosis, and hypoalbuminemia are significant predictors of heparin resistance in cardiac surgery.
  • These findings aid in anticipating and managing HR, potentially improving outcomes during CPB.
  • Further research may focus on tailored anticoagulation strategies for at-risk patients.

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