Safety of vasopressor use in head and neck microvascular reconstruction: A prospective observational study

Objectives. To evaluate the safety of intraoperative vasopressor administration in a prospective series of patients undergoing free tissue transfer surgery for a variety of indications. Study Design. Prospective observational noninferiority study. Setting. Tertiary academic hospital. Subjects. A total of 169 consecutive patients undergoing free tissue transfer for a variety of indications between late 2007 and 2009. Methods. Intraoperative vasopressor use and surgical outcomes data were prospectively collected. This study was designed to test the noninferiority of intraoperative vasopressor exposure versus no intraoperative vasopressor use on early flap failure. Results. A total of 169 free flaps were performed during the study period. Six early free flap failures occurred overall. The proportion of patients experiencing early flap failure was 4.4% (4/90) in those exposed to intraoperative vasopressors versus 2.5% (2/79) in those not exposed, with an absolute difference of 1.9 percentage points (90% confidence interval, -1.4 to 5.2). Thirty-eight percent of patients in the vasopressor group experienced medical and/or surgical complications other than total flap loss versus 43% in the nonvasopressor group (odds ratio, 0.80; 95% confidence interval, 0.43-1.49). Conclusions. Intraoperative vasopressor use may be more common than previously realized in free tissue transfer surgery. Intraoperative vasopressor use does not result in a significant absolute increase in the rate of flap deaths.