Worsening Emergency Department Heart Rate Trajectory and Clinically Significant 7-Day Bouncebacks.

BACKGROUND: Discharge vital signs are used in emergency department (ED) risk assessment, but the association between heart rate (HR) trajectory and adverse outcomes after ED discharge remains unclear. STUDY OBJECTIVE: To evaluate whether an increase in heart rate from triage to discharge is associated with clinically significant 7-day bounceback among discharged adult ED patients. METHODS: We conducted a retrospective cohort study of adults discharged from a tertiary academic ED between February 1 and April 30, 2025. The primary predictor was HR increase ≥10 bpm from triage to discharge. The primary outcome was clinically significant 7-day bounceback, defined as a related return visit resulting in admission, observation, transfer, or death. Multivariable logistic regression adjusted for age, sex, comorbidities, and triage acuity. RESULTS: The cohort included 6635 encounters. Any 7-day ED returns occurred at similar rates among patients with and without HR increase ≥10 bpm, 44 of 415 (10.6%) vs. 664 of 6220 (10.7%), respectively. In contrast, clinically significant bouncebacks occurred in 7 of 415 with HR increase ≥10 bpm (1.7%) compared with 30 of 6220 without it (0.5%). HR increase ≥10 bpm was associated with clinically significant bouncebacks after adjustment, aOR 3.10, 95%CI 1.35-7.13, p = 0.008. Discharge tachycardia alone was not associated with clinically significant bouncebacks, aOR 1.08, 95% CI 0.26-4.51, p = 0.921. CONCLUSIONS: Among discharged adult ED patients, HR increase ≥10 bpm was associated with clinically significant 7-day bounceback but not with any all-cause 7-day ED return. Heart rate trajectory may serve as an additional prompt for reassessment before ED discharge.