A Prospective Study of Microvascular Free-Flap Surgery and Outcome

Abstract

Over a 6-month period, 23 members of the International Microvascular Research Group participated in a prospective survey of their microvascular free-flap practice. Data were recorded with each case for 60 variables covering patient characteristics, surgical technique, pharmacologic treatment, and postoperative outcome. A total of 493 free flaps were reported with a representative demographic distribution for age, sex, indications for surgery, risk factors, flap type, surgical technique, and pharmacologic intervention. Mixed effects logistic regression modeling was used to determine predictors of flap failure and associated complications. The overall incidence of flap failure was 4.1 percent (20 of 493). Reconstruction of an irradiated recipient site and the use of a skin-grafted muscle flap were the only statistically significant predictors of flap failure, with increased odds of failure of 4.2 (p = 0.01) and 11.1 (p = 0.03), respectively. A postoperative thrombosis requiring re-exploration surgery occurred in 9.9 percent of the flaps. The incidence of this complication was significantly higher when the flap was transferred to a chronic wound and when vein grafts were needed, with increased odds of failure of 2.9 (p = 0.02) and 2.5 (p = 0.02), respectively. There was a lower incidence of postoperative thrombosis when rectus/transverse rectus abdominis muscle (TRAM) flaps were used, where odds of failure decreased by 0.36 (p = 0.04), and when subcutaneous heparin was administered in the postoperative period, where odds decreased by 0.27 (p = 0.04). There was an overall 69-percent salvage rate for flaps identified with a postoperative thrombosis. Intraoperative thrombosis occurred in 41 cases (8.3 percent) and was observed more frequently in myocutaneous flaps or when vein grafts were needed (5.5 and 5.0 greater odds, respectively; p < 0.001) but was not associated with higher flap failure (2 of 41 cases; 4.9-percent failure rate). The incidence of a hematoma and/or hemorrhage was increased in obese patients and when vein grafts were needed [2.7 (p = 0.02) and 2.6 (p = 0.03) greater odds, respectively], whereas this complication was significantly decreased in muscle flaps (myocutaneous or skin-grafted muscle), in tobacco users, when a heparinized solution was used for general wound irrigation, and when the attending surgeon performed the arterial anastomosis (in contrast to the resident or fellow on staff) (p < 0.05 for each factor). With the multivariable analysis, many factors were found not to have a significant effect on flap outcome, including the recipient site (e.g., head/neck, breast, lower limb, etc.); indications for surgery (trauma, cancer, etc.); flap transfer in extremes of age, smokers, or diabetics; arterial anastomosis with an end-to-end versus end-to-side technique; irrigation of the vessel without or with heparin added to the irrigation solution; and a wide spectrum of antithrombotic drug therapies. These results present a current baseline for free-flap surgery to which future advances and improve...

Risk Factors of Anastomotic Thrombosis in 200 Head and Neck Free Flaps among Asian Patients

“…Obesity was statistically not a predictor of postoperative thrombosis in our study, and as shown in another study [13]. No other studies have evaluated obesity and postoperative anastomotic thrombosis restricted to the head and neck region.…”

“…In clinical practice, diabetes shows no apparent increased incidence of thrombosis [4,13]. Similarly, our results revealed no relation between postoperative thrombosis and diabetic patients.…”

Characteristics and Intraoperative Treatments Associated with Head and Neck Free Tissue Transfer Complications and Failures

“…2-4,19-21 This retrospective study found that perioperative complication was significantly associated with intraoperative blood loss, while rate of intraoperative fluids received did not reach statistical significance, when controlling for confounding variables. Surgical failure was significantly associated with surgical indication other than cancer and preoperative diagnosis of coronary artery disease.…”

A Review of Thrombosis and Antithrombotic Therapy in Microvascular Surgery

“…Khouri et al [64] found a nonsignificant decrease in flap failure when preoperative aspirin, dextran or heparin was used. Several surgeons recommend the use of heparin administered preoperatively, especially in at-risk patients.…”