A Study on the Effect of Low Molecular Weight on Potassium Homeostasis in Patients Administered Heparin for Thromboprophylaxis in a Tertiary Care Hospital

Objective: Low molecular weight heparin (LMWH) is an indirect thrombin inhibitor used clinically as an anticoagulant for thromboprophylaxis of patients at risk of deep vein thrombosis. The study was done to assess the magnitude of rise in serum potassium after administration of low molecular weight heparin comparing enoxaparin with dalteparin and to evaluate the frequency of clinically significant hyperkalemia in the population studied. Methods: The study was done as a prospective non-randomized observational study in a population of 32 patients started on heparin for thromboprophylaxis for deep venous thrombosis, pulmonary thromboembolism or stroke. Results: A statistically significant elevation in serum potassium was seen in patients treated with LMWH (p = 0.007). The magnitude of rise in potassium was significantly higher in enoxaparin (p = 0.008) than the dalteparin group (p = 0.447). A clinically relevant hyperkalemia of>5 mEq/l was seen in 25% of the population studied. Other important associations detected from the study were that the advancing age and increasing dose could be potential risk factors contributory to an accentuated rise in serum potassium which may culminate in clinically significant hyperkalemia. Conclusion: The study has highlighted that the likelihood of rise in potassium levels during LMWH therapy necessitates monitoring of serum potassium.