The role of meperidine in reduction of postanesthetic shivering and its possible impact on flap outcomes.

Postoperative vascular compromise is a common but critical complication requiring emergent re-exploration, and remains a chief cause of free flap failure. This study investigated the relationship between postanesthetic shivering (PAS) and the development of postoperative complications associated with free flap reconstruction. One hundred thirty-six patients who underwent head and neck cancer resection and free flap reconstruction were retrospectively enrolled. Fifteen patients were assigned to the PAS group, while the others were assigned to the non-PAS (NPAS) group. The odds ratios of acute re-exploration or total failure of the free flap in the PAS group was 3.5 and 14.9, respectively. The dose of meperidine was positively correlated with PAS prevention in our statistical ROC curve analysis. The minimum effective dose of meperidine for PAS prevention was 0.35 mg/kg with 75% sensitivity and 60% specificity. These findings indicate that an optimal dose of meperidine could prevent PAS, which is shown to be associated with a decrease in the incidence of the early post-surgical re-exploration rate of these free flaps related to circulatory compromise.