Factors associated with skin graft take in fibula and radial forearm free flap donor sites

Learning objectives: Identify factors associated with skin graft take in fibula free flaps (FFF) and radial forearm free flaps (RFFF) donor sites. Study objectives: To determine which factors are associated with decreased skin graft take at the donor site in FFF and RFFF in head and neck patients. Design: Retrospective Chart Review Case Series. Setting: Multicenter Tertiary Care. Methods: A multicenter retrospective review was performed at three institutions identifying patients who underwent free tissue transfer, specifically either FFF or RFFF, between 2007 and 2017. Patient demographics, medical history, and social history were examined including age, gender, BMI, smoking status, diabetes and preoperative anticoagulation use. Preoperative, intraoperative data, and postoperative data were also examined including tourniquet use, type of flap, area of skin graft, if the skin graft had a donor site or if it was taken from the flap, wound NPWT use, cast use, use of physical therapy, DVT prophylaxis, limb ischemia, heparin drip, and postoperative aspirin use. Statistical analysis was used to determine which factors were significantly associated with skin graft take. Results: 1415 patients underwent a forearm or fibula flap and 938 patients underwent split-thickness skin graft. Of these, 592 patients had sufficient information and were included in the final analysis. There were 371 males and 220 females. The average age was 55.7. Complete skin graft take was seen in 480 patients (81.1%). On univariate analysis, patients with diabetes (p =.003), type of flap (fibula p <.001), skin graft area (p =.006), tourniquet use (p =.003), DVT prophylaxis (p =.008) and casting (p =.003) were significantly associated with decreased skin graft take rate. In a multivariate analysis, diabetes (OR 2.17 (95%CI 1.16–3.98)), fibula flaps (OR 2.86 (95%CI 1.79–4.76)), an increase in skin graft area (OR 1.01 (95%CI 1.01–1.01)), post-operative aspirin (OR 2.63 (95%CI 1.15–5.88), and casting (OR 2.94 (95%CI 1.22–7.14)) were associated with poor rates of skin graft take. Conclusion: Several factors affect skin graft take rate and should be considered when performing a skin graft for a donor site defect.