The role of systemic unfractionated heparin in free flap surgery outcomes: A retrospective study from a tertiary care hospital in Karachi, Pakistan Authors Osama Ahmed Qureshi Department of Plastic Surgery, Liaquat National Hospital, Karachi, Pakistan Shehab Beg Department of Plastic Surgery, Liaquat National Hospital, Karachi, Pakistan Shahab Ghani Department of Plastic Surgery, Liaquat National Hospital, Karachi, Pakistan Asad Waqar Department of Orthopaedics, Liaquat National Hospital, Karachi, Pakistan Tooba Malik Final Year MBBS Student, Liaquat National Hospital, Karachi, Pakistan Mohsin Anwer Department of Urology, Liaquat National Hospital, Karachi, Pakistan DOI: https://doi.org/10.47391/JPMA.22651 Keywords: Heparin, Haematoma, Microsurgery, Venous insufficiency, Thrombosis Abstract Objective: To assess the short-term impact of postoperative low-dose heparin on arterial insufficiency and venous congestion in free flap surgeries. Method: The retrospective study was conducted at the Liaquat National Hospital, Karachi, and comprised data from January 2021 to July 2023 of patients of either gender aged 16-65 years who underwent primary reconstruction using free flap surgery and having no history of anticoagulation drugs. The patients were divided into two groups. Group A received postoperative low-dose unfractionated heparin (2500IU, three times daily for 5 days), while Group B did not receive any heparin postoperatively, except for a 5000IU intraoperative dose. Patient demographics, flap monitoring and complications, such as arterial insufficiency and venous congestion, were recorded. Data was analysed using SPSS v25. Results: Of the 184 patients with mean age of 36.5 ± 12.56 years (Range 18-66 years), 92(50%) were in each of the two groups. Both the groups had 56(60.9%) male and 36(39.1%) female patients. Arterial insufficiency was observed in 20(21.7%) patients in Group A and 27(29.3%) in Group B. Venous congestion occurred in 27(29.3%) patients in both the groups (p=1.000). Combined arterial insufficiency and venous congestion rates were 47(51.1%) in Group A and 54(58.7%) in Group B (p=0.300). Diabetes and hypertension were significant predictors of arterial insufficiency (p<0.05). Conclusion: Postoperative low-dose heparin administration did not significantly reduce the risk of arterial insufficiency or venous congestion in free flap surgery. Comorbidities, like diabetes and hypertension, were associated with higher complication rates. Key Words: Heparin, Haematoma, Microsurgery, Venous insufficiency, Thrombosis. Downloads Full Text Article Published 2026-07-12 How to Cite Qureshi, O. A., Shehab Beg, Shahab Ghani, Asad Waqar, Tooba Malik, & Mohsin Anwer. (2026). The role of systemic unfractionated heparin in free flap surgery outcomes: A retrospective study from a tertiary care hospital in Karachi, Pakistan. Journal of the Pakistan Medical Association, 76(8), 1248–1251. https://doi.org/10.47391/JPMA.22651 More Citation Formats ACM ACS APA ABNT Chicago Harvard IEEE MLA Turabian Vancouver Download Citation Endnote/Zotero/Mendeley (RIS) BibTeX Issue Vol. 76 No. 8 (2026): AUGUST Section RESEARCH ARTICLE License Copyright (c) 2026 Journal of the Pakistan Medical Association This work is licensed under a Creative Commons Attribution 4.0 International License.