Interfacility Emergency Department Transfer for Mandibular Fractures in the United States

Interfacility hospital transfer for isolated mandibular fractures is common but rarely clinically necessary. The purpose of this study was to generate nationally representative estimates regarding the incidence, risk factors, and cost of transfer for isolated mandibular fractures.

This was a retrospective cohort study using the Nationwide Emergency Department Sample 2018 to identify patients with isolated mandibular fractures. The primary predictor variable was hospital trauma center designation (Level I, Level II, Level III, and nontrauma center). The primary outcome variable was hospital transfer. Total emergency department (ED) charges were also assessed. Covariates were demographic, medical, injury-related, and hospital characteristics. Descriptive, bivariate, and multiple logistic regression statistics were used to evaluate the incidence and predictors of interfacility transfer.

A total of 28,357 encounters with mandibular fracture as the primary diagnosis were included. Within this cohort there were 2,893 hospital transfers (10.2%). In unadjusted analysis, evaluation at a nontrauma center, level III trauma center, metropolitan nonteaching hospital, nonmetropolitan nonteaching hospital, micropolitan region, and history of cerebrovascular event was associated with hospital transfer (P ≤ .001). In the adjusted model, independent predictors (risk factors) for hospital transfer were evaluation at a nontrauma center (P ≤ .001, odds ratio [OR] = 12.8, 95% confidence interval [CI] = 6.43 to 25.4), level III trauma center (P ≤ .001, OR = 10.7, 95% CI = 5.25 to 21.7), nonmetropolitan nonteaching hospital (P ≤ .001, OR = 2.45, 95% CI = 1.73 to 3.46), metropolitan nonteaching hospital (P ≤ .001, OR = 1.57, 95% CI = 1.20 to 2.06), cervical spine injury (P = .002, OR = 3.53, 95% CI = 1.61 to 7.75), fractures of the mandibular body (P = .007, OR = 1.33, 95% CI = 1.08 to 1.64), and unspecified mandibular fractures (P = .006, OR = 1.49, 95% CI = 1.12 to 1.99). The average ED charge per encounter was $7,482 ± 565 for a total nationwide charge of $212,172,264. Transferred subjects had total ED charges of $25,632,974, not including additional charges incurred at the recipient hospital.

Isolated mandibular fractures are common injuries that are frequently transferred and cost the healthcare system millions of dollars annually. Hospital characteristics rather than medical or injury-related variables were the strongest predictors of transfer, suggesting that transfers are primarily driven by need to access maxillofacial surgical services. Programs evaluating necessity of transfer and facilitating specialist evaluation in the outpatient setting may reduce healthcare expenditures for this injury.