In-Hospital Outcomes and Costs Among Patients Hospitalized During a Return Visit to the Emergency Department.

Importance Unscheduled short-term return visits to the emergency department (ED) are increasingly monitored as a hospital performance measure and have been proposed as a measure of the quality of emergency care. Objective To examine in-hospital clinical outcomes and resource use among patients who are hospitalized during an unscheduled return visit to the ED. Design, Setting, and Participants Retrospective analysis of adult ED visits to acute care hospitals in Florida and New York in 2013 using data from the Healthcare Cost and Utilization Project. Patients with index ED visits were identified and followed up for return visits to the ED within 7, 14, and 30 days. Exposures Hospital admission occurring during an initial visit to the ED vs during a return visit to the ED. Main Outcomes and Measures In-hospital mortality, intensive care unit (ICU) admission, length of stay, and inpatient costs. Results Among the 9 036 483 index ED visits to 424 hospitals in the study sample, 1 758 359 patients were admitted to the hospital during the index ED visit. Of these patients, 149 214 (8.5%) had a return visit to the ED within 7 days of the index ED visit, 228 370 (13.0%) within 14 days, and 349 335 (19.9%) within 30 days, and 76 151 (51.0%), 122 040 (53.4%), and 190 768 (54.6%), respectively, were readmitted to the hospital. Among the 7 278 124 patients who were discharged during the index ED visit, 598 404 (8.2%) had a return visit to the ED within 7 days, 839 386 (11.5%) within 14 days, and 1 205 865 (16.6%) within 30 days. Of these patients, 86 012 (14.4%) were admitted to the hospital within 7 days, 121 587 (14.5%) within 14 days, and 173 279 (14.4%) within 30 days. The 86 012 patients discharged from the ED and admitted to the hospital during a return ED visit within 7 days had significantly lower rates of in-hospital mortality (1.85%) compared with the 1 609 145 patients who were admitted during the index ED visit without a return ED visit (2.48%) (odds ratio, 0.73 [95% CI, 0.69-0.78]), lower rates of ICU admission (23.3% vs 29.0%, respectively; odds ratio, 0.73 [95% CI, 0.71-0.76]), lower mean costs ($10 169 vs $10 799; difference, $629 [95% CI, $479-$781]), and longer lengths of stay (5.16 days vs 4.97 days; IRR, 1.04 [95% CI, 1.03-1.05]). Similar outcomes were observed for patients returning to the ED within 14 and 30 days of the index ED visit. In contrast, patients who returned to the ED after hospital discharge and were readmitted had higher rates of in-hospital mortality and ICU admission, longer lengths of stay, and higher costs during the repeat hospital admission compared with those admitted to the hospital during the index ED visit without a return ED visit. Conclusions and Relevance Compared with adult patients who were hospitalized during the index ED visit and did not have a return visit to the ED, patients who were initially discharged during an ED visit and admitted during a return visit to the ED had lower in-hospital mortality, ICU admission rates, and in-hospital costs and longer lengths of stay. These findings suggest that hospital admissions associated with return visits to the ED may not adequately capture deficits in the quality of care delivered during an ED visit.