Out-of-hospital cardiac arrests rose when local COVID-19 prevalence high
Most cities experienced significant increases in out-of-hospital cardiac arrest that paralleled spikes in local COVID-19 prevalence, researchers reported.
“The highly stressful clinical challenge of out-of-hospital cardiac arrest occurs frequently and somewhat predictable with about 30,000 cases routinely presenting each month in North America and a similar proportionate number in European nations,” Kevin E. McVaney, MD, specialist in the department of emergency medicine at the University of Colorado School of Medicine and the Denver Health and Hospital Authority, and colleagues wrote in EClinicalMedicine. “However, as SARS-CoV-2 infections began to surge in the first epicenters such as Milan, London, New York and Detroit, their emergency medical services (EMS) agencies were already reporting alarming increases in out-of-hospital cardiac arrest, even prior to implementation of shelter-at-home directives and the tallying of COVID-19-related deaths.”
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Researchers obtained aggregate, de-identified, preexisting monthly out-of-hospital cardiac arrest tallies among adults from EMS medical directors for 50 large U.S. cities. Out-of-hospital cardiac arrest events occurred from January to June 2020. For comparisons, equivalent data were collected from large cities in Italy, the U.K., France, Australia and New Zealand.
The mean number of out-of-hospital cardiac arrests rose from 144 per city per month during 2018-2019 to 231 per city in April 2020 (P = .03). Most U.S. cities had a 20% or more increase in out-of-hospital cardiac arrests during April 2020 compared with 2018-2019. These increases in out-of-hospital cardiac arrest cases also reflected the high local prevalence of COVID-19.
In April 2020, there was a 1.5-fold increase in out-of-hospital cardiac arrests among 13 U.S. cities, and three COVID-19 epicenters — New York City, Detroit and Washington, D.C. — more than doubled their usual numbers for out-of-hospital cardiac arrest events; there was a 2.5-fold increase in New York City. Researchers observed unchanged or diminished numbers of out-of-hospital cardiac arrest events in cities with lesser COVID-19 impact.
During April 2020, on average, there was a 59% increase in out-of-hospital cardiac arrest cases per city (P = .03). London, Milan, New York City, Detroit, St. Louis and New Orleans had the highest out-of-hospital cardiac arrest increases but returned to or approached the pre-COVID numbers after mitigation of the spread of COVID-19 in June 2020. However, cities that were minimally affected by COVID-19 during April 2020 experienced marked out-of-hospital cardiac arrest increases when they had local surges of COVID-19 infections.
Throughout the study period, Albuquerque, New Mexico; Pittsburgh; Cleveland; Auckland, New Zealand; and Perth, Australia, were relatively less affected by COVID-19 and demonstrated negligible changes in out-of-hospital cardiac arrest events.
Cities in Europe, Australia and New Zealand demonstrated similar experiences in out-of-hospital cardiac arrest events during the COVID-19 pandemic as the U.S.
“Out-of-hospital cardiac arrest is likely a direct consequence of SARS-CoV-2 infection and considering that testing and eventual documentation of COVID-19 may be somewhat delayed after disease onset, observations of sudden increased frequencies in out-of-hospital cardiac arrest may serve as a signal of COVID-19 surges and cluster areas,” the researchers wrote. “In most of the cases, these many thousands of additional out-of-hospital cardiac arrest cases were not resuscitated and not tested for COVID-19 and therefore not counted among COVID-19-related deaths.”