Q: 54 year old male is scheduled for Coronary Artery Bypass (CABG). On review of medical record from previous admissions you noticed possible occurrence of  HIT (Heparin Induced Thrombocytopenia) 2 years ago after his unstable angina episode. You ordered Heparin antibodies STAT and are reported negative. What is your recommendation to surgeon?

Answer: 

Patient with a history of HIT who requires cardiopulmonary bypass can safely be anticoagulated with heparin, provided 2 conditions

•  HIT antibodies are absent and
• the heparin exposure is limited to the operative procedure only

Bivalirudin has also been recommended for patients with risk of HIT who are undergoing CABG but its use remained low due to concern of high bleeding during bypass.