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Intraoperative Use of Vasopressors Is Safe in Head and Neck Free Tissue Transfer.

BACKGROUND
The purpose of this study is to identify whether intraoperative use of vasoactive medications increases the risk of free flap failure or complications through a systematic review and meta-analysis.


MATERIALS AND METHODS
PubMed/MEDLINE, EMBASE, and Scopus databases were searched for studies published through January 2015. English publications that met the following criteria were included: (1) adult patients undergoing head and neck free flap reconstruction; (2) comparison of patients with and without intraoperative vasopressor administration; and (3) documentation of flap failure rate and/or flap complications. The primary outcome was the incidence of flap failure. The secondary outcome was the incidence of overall flap complications. Meta-analysis was performed to obtain pooled odds ratios (ORs) of the effect of intraoperative use of vasopressors on flap failure and complication rates.


RESULTS
Four cohort studies met inclusion criteria. All studies were of high methodological quality with an average Methodological Index for Non-Randomized Studies score of 18.75 (range 16-23). A total of 933 patients undergoing head and neck free flap reconstruction were included. Meta-analysis demonstrated no statistically significant difference in the incidence of flap failure (2.9 vs. 3.6%; OR, 0.68; 95% confidence interval [CI], 0.23-1.99; p = 0.48) or incidence of flap complications (16.8 vs. 18.6%; OR, 0.92; 95% CI, 0.60-1.42; p = 0.71).


CONCLUSION
Based on the current evidence, intraoperative use of vasopressors has no impact on the incidence of flap failure or flap complications.