Key Points
Question Are emergency department (ED) boarding and inpatient census associated with interhospital transfer (IHT) acceptances?
Findings This cross-sectional study of 26 020 IHT requests found that the severity of ED boarding and inpatient census were associated with declining IHT acceptance.
Meaning These findings suggest that physicians at overcrowded referral hospitals face tradeoffs with implications for both rural and urban patients as they seek to fulfill seemingly conflicting obligations to safely care for locally hospitalized patients and accept regional patients seeking transfer.
Abstract 
Importance Referral hospitals in the US are experiencing unprecedented levels of crowding, leading them to increasingly refuse interhospital transfer (IHT) requests. Crowded hospitals are dangerous, but refusing IHTs undermines the role of referral hospitals and may cause harm.
Objective To measure associations of hospital crowding measures (emergency department [ED] boarding and inpatient census) with IHT acceptances overall and for prioritized conditions.
Design, Setting, and Participants This cross-sectional study from January 2019 to May 2023 analyzed data from the only academic and level I trauma center in a highly rural state in the Southwestern US, including transfer center data, ED boarding hours, and inpatient census. All transfer center calls regarding adults (age >18 years) were eligible for the study. Data were analyzed from June to October 2024.
Main Outcome and Measures The primary outcome was the proportion of transfer requests accepted on a weekly and monthly basis. Adjusted logistic regression was used to analyze associations of ED boarding time and inpatient census with IHT acceptance, considering prioritized conditions (obstetrics, ST-elevation myocardial infarction [STEMI], stroke, and trauma) and rurality. Transfer data contained IHT request descriptors, including referring facility, date and time of call, decision (accept or decline), diagnosis, and patient demographics. ED boarding was measured daily as a sum of all boarding hours for each ED patient.
Results The study included 26 020 IHT requests (11 267 women [43.2%]; mean [SD] age, 54.4 [19.6] years), of which 16 062 were accepted (61.7%). There were 22 119 (85.0%) requests from urban and 3901 requests (15.0%) from rural hospitals, with the majority of IHT requests (19 912 requests [76.3%]) seeking transfer from an ED. There was a negative correlation between IHT acceptance and ED boarding (Pearson r, −0.73) and inpatient census (Pearson r, −0.87). At times of worst ED boarding (highest vs lowest quartile), the odds of IHT acceptance were lower (adjusted odds ratio [aOR], 0.71; 95% CI, 0.66-0.78). Of the 3901 rural requests, 2196 (56.3%) were accepted, with lower odds of acceptance for rural vs urban requests (aOR, 0.66; 95% CI, 0.64-0.79). Prioritized diagnoses were more commonly accepted, particularly obstetrics (aOR, 5.28; 95% CI, 4.17-6.70), STEMI (aOR, 3.04; 95% CI, 1.86-4.98), and trauma (aOR, 3.19; 95% CI, 2.86, 3.57).
Conclusions and Relevance In this cross-sectional study of IHT requests, the severity of ED boarding and inpatient census were associated with decreased IHT acceptance, suggesting that overcrowded referral hospitals face tradeoffs as they seek to fulfill seemingly conflicting obligations to safely care for locally hospitalized patients and accept regional patients seeking transfer.
