BackgroundFree tissue transfer encompasses a variety of techniques by which tissue is moved to another region of the body, with anastomosis of the divided artery and vein. Currently, success rates are reported at 91-99% [1], however, little is known regarding predictors for adverse outcomes.We aim at identifying predictors for negative outcomes following free flap surgery; and predict that elderly patients and patients with head and neck free flaps will have inferior outcomes due to comorbidity.MethodsThis is a retrospective case series. All free flap surgeries between 02/2018 to 02/2021 were identified using the electronic operation record system at Flinders Medical Centre. Chi squared hypothesis testing assessed patient factors and implications on outcome. Results67 patients of varying demographics were included in this study. The odds of wound infection was much higher in patients aged older than 65 (OR: 4.1 (95%CI 1.24-13.6, z-score: 2.31, p=0.017)). The odds of unplanned reoperation was also higher in this population (OR: 13.7 (95%CI 1.42-132.9, p=0.0053)). Free flap location was significant in determining whether patients would require a subsequent blood transfusion (p=0.0071). Head and neck patients did not experience a higher rate of adverse events.ConclusionPatients aged 65 and older are more likely to require treatment for infection and more often require reoperation because of flap related issues. Patients with limb free flaps are more likely to require transfusions. Head and neck patients did not have higher complication rates.