Is the Use of Dexmedetomidine Upon Emergence From Anesthesia Associated With Neck Hematoma Formation Following Head and Neck Microvascular Reconstruction?

Background: Dexmedetomidine (DEX) is a highly selective alpha-2-receptor agonist, and its use has not been well studied in major microvascular reconstructive surgery of the head and neck.

Purpose: The purpose is to measure the association between DEX and neck hematoma formation in subjects undergoing head and neck microvascular reconstructive surgery.

Study Design, Setting, Sample: The investigators implemented a retrospective cohort study on subjects undergoing microvascular head and neck reconstruction for benign and malignant pathology at the University of Alabama at Birmingham from 2014 to 2021. Patients with unresectable tumors were excluded.

Predictor Variable: The predictor variable was the intraoperative use of DEX upon emergence from general anesthesia. Subjects received standard anesthetic drugs and DEX, while control subjects received only standard anesthetic drugs.

Main Outcome Variable(s): The primary outcome was postoperative neck hematoma formation necessitating a return to the operating theater. The secondary outcome was the length of stay (LOS).

Covariates: The covariates were demographic, operative, and oral morphine equivalents of anesthesia drugs.

Analyses: Bivariate analyses were performed using the Student's t-test and the χ test for continuous and categorical variables. Multivariate regression analyses were conducted to assess for associations between DEX and the outcomes adjusted for confounding variables when present. P values of < .05 were regarded as statistically significant.

Results: A total of 297 subjects (mean age, 59.6 years, and standard deviation [SD], 14.9) with 61.6% male received DEX, and 304 subjects (mean age, 58.9 years, and SD, 14.6) with 60.2% male served as controls (P > .5). A total of 11 postoperative neck hematoma occurred in the control group when compared to 2 in the DEX (relative risk = 5.4, 95% confidence interval [CI], 1.2 to 24, P = .02). The mean LOS was 7.7 (SD, 4.3) and 9.4 (SD, 8.1) for the DEX and control groups (95% CI, 0.7 to 2.8, P < .01). After adjusting for tobacco history, tracheostomy, and neck dissection, DEX (Beta coefficient (B) = -1.7, 95% CI -2.7 to -0.7, P < .01) and neck dissection (B = 2.2, 95% CI 1.0 to 3.4, P < .01) were statistically associated with LOS.

Conclusion And Relevance: The use of intraoperative DEX upon emergence from general anesthesia was associated with lower postoperative neck hematoma formation and a shorter length of stay following microvascular head and neck reconstruction.