Intraoperative Fluid Management Implies Insignificant Influence to Surgical Outcomes in Head and Neck Microvascular Reconstruction Cases

Background: Deliberate fluid administration has been used to maintain a hyperdynamic systemic circulation in free tissue transfer operations. The effects of intraoperative volume loading on postoperative complications have been controversial. The authors hypothesized that increasing intraoperative fluid administration was associated with increased postoperative surgical complications. Methods: Free flap operations for head and neck reconstruction between 2004 and 2014 were reviewed. A generalized estimating equation model was used to estimate the effect of intraoperative fluid administration on surgical outcomes. The optimized thresholds of anesthetic time were tested by the Youden index for flap compromise and major complications. Results: A total of 2983 consecutive cases were included in the study. The incidences of flap compromise and total loss were 1.5 and 3.3 percent, respectively. Intraoperative fluid administration was not associated with surgical complications (p = 0.195). However, a 1-hour increase in anesthesia time was associated with a 19 percent increased risk of flap compromise (adjusted OR, 1.19; 95 percent CI, 1.10 to 1.29; p < 0.001). Conclusion: Prolonged anesthetic time, but not fluid administration, was associated with adverse surgical outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.