Abstract

A STUDY ON DOSING OF HEPARIN AND MONITORING aPTT IN A TERTIARY CARE TEACHING HOSPITAL

Akhila S. Arjun*, Shiji S. Mathew, Sruti Sunil Soman and Vidhu Annie Sajan

ABSTRACT

A prospective observational study was conducted for a period of 6 months. The objective was to compare the prescribed heparin dose with standard heparin dose based on body weight and indication and to categorize the number of patients achieving therapeutic, subtherapeutic, supratherapeutic range at 6th, 24th, 48th hours. Eighty cases were collected and analyzed. aPTT values were monitored and dose adjustment were indicated for patients with aPTT above and below the therapeutic range. Comparison of prescribed IV Bolus heparin dose with standard heparin dose revealed that 37 patients received appropriate dose, 35 received overdose and 2 received underdose. Comparison of prescribed IV infusion heparin dose with standard heparin dose revealed that 36 patients received appropriate dose, 33 received underdose and 5 received overdose. Out of which, 43 were subtherapeutic, 27 therapeutic, and 4 supratherapeutic aPTT at 6th hour. At 24th hour, 33 were subtherapeutic,24 were therapeutic and 3 showed supratherapeutic. At 48th hour, 14 were subtherapeutic,13 were therapeutic and 2 showed supratherapeutic. Out of 74 patients, 28 showed heparin resistance. We identified that the factors responsible for heparin resistance were gender and age whereas BMI was insignificant. Adopting an approved heparin guideline with monitoring of aPTT and dosage adjustment accordingly, will result in greater therapeutic efficacy and minimal risk of adverse drug reactions.

Keywords: Heparin, aPTT, Weight based dosing, Heparin resistance.