Effect of the COVID-19 Pandemic on Emergency Department Visits of Patients with an Emergent or Urgent Diagnosis.

Purpose: During the coronavirus disease 2019 (COVID-19) pandemic, visits to emergency department (ED) have significantly declined worldwide. The purpose of this study was to identify the trend of visits to ED for different diseases at the peak and slack stages of the epidemic. Patients and Methods: This was a retrospective observational study conducted in a tertiary referral medical center in northern Taiwan. We recorded weekly ED visits for myocardial infarction with or without ST-elevation (STEMI or NSTEMI), out-of-hospital cardiac arrest (OHCA), acute stroke, and congestive heart failure from 2016 to 2021. We compared the local epidemic peak periods (calendar weeks 4-18, 2020 and calendar weeks 21-31, 2021) and its corresponding slack periods (calendar weeks 4-18, 2021 and calendar weeks 21-31, 2020) with the baseline period (2016-2019) using Mann-Whitney test to identify the difference. Results: We observed a significant decline in ED visits (median [Q1, Q3]) during the epidemic for OHCA (6 [5, 7] and 5 [4, 6], p = 0.046, for baseline and peak period, respectively, in week 4-18), acute stroke (41.5 [38, 47] and 35 [28, 39], p < 0.001, in week 4-18, 40 [35, 45] and 35 [28, 40], p = 0.039, in week 21-31) and CHF (28 [24.25, 33] and 19 [12, 23], p < 0.001, in week 4-18, 18 [16, 23] and 13 [11, 16], p = 0.001, in week 21-31). Significant difference was not observed in patients with NSTEMI and STEMI in both week 4-18 and 21-31, and cardiac arrest in week 21-31. There was a rebound in ED visits in the slack period. Conclusion: This study revealed that ED visits significantly declined during the COVID-19 epidemic and rebounded in the slack period. The trend was significant for acute stroke and heart failure but was relatively less prominent effect for emergent events such as cardiac arrest or myocardial infarction.