Published: 2022-08-24

Comparative study between effectiveness of low molecular weight heparin injection and unfractionated heparin in terms of morbidity and outcome in COVID-19 cases

Meet S. Bhuta, Sapna D. Gupta


Background: The novel coronavirus 2019 presented a variety of disease spectrums that range from asymptomatic to sepsis with multi-organ dysfunction and death. One of the mechanisms being a hypercoagulable state with micro and macro-circulatory thrombosis is found in critically ill COVID-19 patient with ARDS with pathology consistent with a vascular occlusive aetiology of respiratory failure rather than more classic finding of ARDS. Venous thromboembolism, MI, acute peripheral arterial thrombosis is seen in COVID-19. Endothelial cells dysfunction induced by infection causing excess thrombin generation, fibrinolysins shutdown, hypoxia inducible transcription factor dependent signalling pathways, increasing blood viscosity leading to Hypercoagulable state. Early application of anticoagulant therapy in severe COVID-19 was suggested for improving outcome in patients with elevated d-dimer. Aim of study was comparing effectiveness of LMWH with unfractionated heparin in outcome of COVID-19.

Methods: This retrospective observational study including 400 patients meeting inclusion criteria were divided 2 groups out of which 200 patients were treated with inj. LMWH and other 200 were treated with injection heparin and various parameters were compared. A probability value (p value) of less than or equal to 0.05 was considered statistically significant.

Results: Death rate is seen lower with LMWH in critically ill patients with high discharge rate with minimal lab parameter derangement and high efficacy to lower down inflammatory markers (LDH, ferritin, CRP, D-dimer, ESR) in comparison to unfractionated heparin.

Conclusions: Early use of LMWH may be beneficial for the outcome.


COVID-19 pneumonia, Hypercoagubility, LMWH, Unfractionated heparin

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