Cohort study of the characteristics and outcomes in patients with COVID-19 and in-hospital cardiac arrest

Abstract

Objective: We studied characteristics, survival, causes of cardiac arrest, conditions preceding cardiac arrest, predictors of survival and trends in the prevalence of COVID-19 among in-hospital cardiac arrest (IHCA) cases.

Design and setting: Registry-based observational study.

Participants: We studied all cases (≥18 years of age) of IHCA receiving cardiopulmonary resuscitation in the Swedish Registry for Cardiopulmonary Resuscitation during 15 March 2020 to 31 December 2020. A total of 1613 patients were included and divided into the following groups: ongoing infection (COVID-19+; n=182), no infection (COVID-19-; n=1062) and unknown/not assessed (n=369).

Main outcomes and measures: We studied monthly trends in proportions of COVID-19 associated IHCAs, causes of IHCA in relation to COVID-19 status, clinical conditions preceding the cardiac arrest and predictors of survival.

Results: The rate of COVID-19+ patients suffering an IHCA increased to 23% during the first pandemic wave (April), then abated to 3% in July, and then increased to 19% during the second wave (December). Among COVID-19+ cases, 43% had respiratory insufficiency or infection as the underlying cause of the cardiac arrest, compared with 18% among COVID-19- cases. The most common clinical sign preceding cardiac arrest was hypoxia (57%) among COVID-19+ cases. OR for 30-day survival for COVID-19+ cases was 0.50 (95% CI 0.33 to 0.76), compared with COVID-19- cases.

Conclusion: During pandemic peaks, up to one-fourth of all IHCAs are complicated by COVID-19, and these patients have halved chance of survival, with women displaying the worst outcomes.

Keywords: COVID-19; adult cardiology; cardiology; coronary heart disease.

Figure 1

Characteristics of in-hospital cardiac arrest (IHCA) according to COVID-19 status. (A) Monthly proportion of COVID-19 status among patients with IHCA, stratified on COVID-19 status. In March only cases after 15 March 2020 were included. (B) Aetiology of IHCA, stratified on COVID-19 status. The y-axis shows percentages for each aetiology in each group. (C) Clinical conditions 1 hour prior to IHCA, stratified on COVID-19 status. Only patients with data regarding the specific condition was included. UNA, unknown/not assessed.

Figure 2

Kaplan-Meier survival curves. Kaplan-Meier survival curves, separately for (A) overall, (B) women, (C) men, (D) age ≥70 year, (E) age <70 year, (F) cancer, (G) Heart failure, (H) diabetes, (I) kidney failure and (J) Myocardial infarction. p=log rank p value. The numbers under the graphs are showing the survival in percentages. regarding myocardial infarction acute MI is presented. CA, cardiac arrest; MI, myocardial infarction; UNA, unknown/not assessed.

Figure 3

OR for 30-day survival. Forest plot with the adjusted OR for 30-day survival among patients with ongoing infection versus no infection and unknown/NA vs no infection. Stratified on overall, men, women, age <70 years, age ≥70 years, heart failure, kidney failure, diabetes, myocardial infarction and cancer. Myocardial infarction (MI) was defined as acute or previous MI. UNA, unknown/not assessed.

Figure 4

OR for 30-day survival. Forest plot with OR for 30-day survival, stratified on the groups, no infection, ongoing infection and overall, all in different colours. The 95% CI is shown between the bars. X-axis has a logarithmic scale. CA, cardiac arrest; CPR, cardiopulmonary resuscitation; MI, myocardial infarction.