Perioperative Care of Free Flap Patients: A Scoping Review of Current Evidence.

Background: Failure of a free flap can occur unpredictably with devastating consequences for the patient. Microvascular surgeons have developed perioperative protocols designed to mitigate the risk of flap failure. Such protocols are highly variable and generally lack consensus. This review aimed to provide the microsurgeon with a current map of the evidence in key aspects of the perioperative care of free flap patients, which can be used to inform clinical decision-making. Methods: A multidatabase scoping review was conducted to identify free flap articles. The articles were then reviewed to determine if they met inclusion criteria. Included articles were then critically appraised and assigned a corresponding level of evidence in accordance with the American Academy of Orthopedic Surgeons Evidence-based Practice Committee. Results: A total of 104 studies of varying quality were included in this review, from which evidence data were extracted and grouped into categories of perioperative free flap care. Conclusions: Despite existing literature, current practice is largely informed by expert opinion instead of evidence-based data. Interventions supported by evidence include delaying flap surgery to optimize patient factors and obtaining baseline blood work. Avoidance of perioperative hypothermia is indicated, but no evidence exists for supplemental postoperative warming. Restrictive protocols for blood transfusions are likely safe. The literature supported clinical monitoring of unburied flaps, but the optimal schedule and duration were unknown. There is evidence to support the use of gabapentin to improve postoperative pain and decrease opioid use. In lower extremity free flaps, allowing early leg dangling is likely safe.