PP153: Safety and efficacy of Low Molecular Weight Dextran (Dextran 40) in head and neck free flap reconstruction

Abstract

Purpose Antithrombotic agents have been used in microvascular surgeries. Low Molecular Weight Dextran (Dextran 40) though used, is not without complications. Materials and methods Retrospective analysis of 172 consecutive flaps. A comparison was done between two groups of patients (86 flaps each) with and without the use of Dextran 40, in terms of safety and efficacy. Results 168 patients underwent 172 microvascular free flaps for reconstruction of head and neck oncologic defects during the study period. The mean age was 55.6 years (range 18–85 years). The groups were comparable in terms of pulmonary, cardiac co-morbidity and history of any prior radiotherapy. Of the 172 flaps, 26 flaps required re-exploration. 21 flaps could be salvaged. There were five total flap failures. The free flap survival rate was 95.9%. The five free flap failures included one radial forearm free flap, two fibular free flaps and two antero-lateral thigh flaps. There were six partial flap losses. Fourteen flaps had venous thrombosis. Four flaps had arterial thrombosis, of which one each in both the groups could not be salvaged. There were seven patients with postoperative hematoma requiring surgical intervention. All of these free flaps survived after hematoma evacuation. None of the patients developed ARDS or required prolonged ventilator support. No patient had dextran related anaphylactoid reactions. 38 patients (43.7%) in Group A had post-operative atelectasis and 21 (25.6%) patients in Group B had this complication. This difference was statistically significant ( p = 0.01). Six patients in Group A developed post-operative pneumonia while five patients in Group B developed this complication. This difference was statistically not significant ( p = 0.93). The mean duration of intensive care unit stay was 6.8 and 6.9 h respectively for the Groups A and B. Similarly, the mean hospital stay was 14.1 and 13.4 days respectively for the groups A and B. These differences were also not significantly different among the groups. Conclusions Though Dextran 40 did not result in any significant adverse local or systemic complications, it is not useful as a post operative antithrombotic agent in head and neck oncologic defect reconstruction with free tissue transfer.