A customized early warning score enhanced emergency department patient flow process and clinical outcomes in a COVID-19 pandemic.

Objective: Patient crowding and boarding in the emergency department (ED) is associated with adverse outcomes and has become increasingly problematic in recent years. We investigated the impact of an ED patient flow countermeasure using an early warning score.

Methods: We conducted a cross-sectional analysis of observational data from patients who presented to the ED of a Level 1 Trauma Center in Pennsylvania. We implemented a modified version of the Modified Early Warning Score (MEWS), called mMEWS, to address patient flow. Patients aged ≥18 years old admitted to the adult hospital medicine service were included in the study. We compared the pre-mMEWS (February 19, 2017-February 18, 2019) to the post-mMEWS implementation period (February 19, 2019-June 30, 2020). During the intervention, low MEWS (0-1) scoring admissions went directly to the inpatient floor with expedited orders, the remainder waited in the ED until the hospital medicine admitting team evaluated the patient and then placed orders. We investigated the association between mMEWS, ED length of stay (LOS), and 24-hour rapid response team (24 hour-RRT) activation. RRT activation rates were used as a measure of adverse outcome for the new process and are a network team response for admitted patients who are rapidly decompensating. The association between mMEWS and the outcomes of ED length of stay in minutes and 24 hour-RRT activation was assessed using linear and logistic regression adjusting for a priori selected confounders, respectively.

Results: Of the total 43,892 patients admitted, 19,962 (45.5%) were in the pre-mMEWS and 23,930 (54.5%) in the post-mMEWS implementation period. The median post-mMEWS ED LOS was shorter than the pre-mMEWS (376 vs 415 minutes;  < 0.01). After accounting for potential confounders, there was a 4.57% decrease in the ED LOS after implementing mMEWS (95% confidence interval [CI], 4.20-4.94;  < 0.01). The proportion of 24 hour-RRT did not differ significantly when comparing pre- and post-mMEWS (33.5% vs 34.4%;  = 0.83).

Conclusion: The use of a modified MEWS enhanced admission process to the hospital medicine service, even during the COVID-19 pandemic, was associated with a significant decrease in ED LOS without a significant increase in 24 hour-RRT activation.