Incidence and Outcomes of Heparin-Induced Thrombocytopenia in Patients Undergoing Vascular Surgery

Abstract

Objective: The National Inpatient Sample (NIS) from years 2010 through 2012 was utilized to determine the incidence, predictive risk factors, and outcomes of heparin-induced thrombocytopenia (HIT) in patients undergoing vascular surgery.

Design: Retrospective population-based study.

Setting: Data from the National Inpatient Sample (NIS) (2011 through 2013) using specific International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedure codes corresponding with vascular surgery.

Participants: 425,379 hospital admissions in patients which underwent vascular surgery. Among these, 1,290 (0.31%) were diagnosed with HIT, and 17,765 (4.18%) were diagnosed with secondary thrombocytopenia.

Measurements and results: The incidence of HIT is 0.3% in the vascular surgery population. The highest incidence is observed in thoraco-subclavian and vein reconstruction procedures. This study indicated that liver disease, endocarditis, chronic renal failure, congestive heart failure, atrial fibrillation, obesity, and female sex are associated with a higher incidence of HIT in this population. In vascular surgery patients, HIT can increase mortality by 3-fold and lead to severe complications such as acute renal failure, venous embolism, pulmonary embolism, and respiratory failure.

Conclusion: The incidence of HIT in the vascular surgery population is similar to previously reported incidence in cardiac surgery patients. In the vascular surgery population, mortality increases 3-fold in patients with HIT versus those without any thrombocytopenia. Understanding the associated risk factors and complications will allow clinicians to make informed decisions and anticipate HIT and associated complications in certain high-risk populations.

Keywords: HIT; NIS database; heparin; heparin induced thrombocytopenia; national inpatient sample; outcomes; platelets; thrombocytopenia; vascular surgery.