Does COVID-19 Affect In-Hospital Cardiac Arrest Survival?

While initial surges and a near total lack of knowledge about COVID-19 are behind us, the pandemic is far from over. As of this writing, the Delta variant is on the rise and now more than ever, clinicians need to consider every factor that may impact survival in COVID patients. But there’s still a lot we don’t know.

For instance, COVID-19 brings more critically ill patients to hospitals across the country. And more critically ill patients means greater incidence of in-hospital cardiac arrest. The critical question is: Are COVID patients less likely to survive IHCA than their non-COVID counterparts?

Published studies present conflicting observations and draw different conclusions about this issue. Let’s take a look at the data, identify potential causes for these inconsistencies, and highlight some solutions that might be beneficial for hospitals and Code Blue response teams moving forward.

Data Overview: In-hospital cardiac arrest survival in COVID-19 patients

In the grand scheme of disease study, we are still in the nascent stages of understanding SARS-CoV-2 and its resulting illness. But we do have a handful of initial studies that seek to determine the impact of COVID on IHCA survival rates.

National pre-COVID-19 IHCA survival rates

First, let’s set our baseline. The average survival-to-hospital-discharge rate for IHCA in the U.S. prior to COVID-19 was 20 – 25%.¹ This figure was already well below the 10-year improvement goal of 35% set by the American Heart Association in 2010, but poorer outcomes have persisted due to myriad addressable factors.²

Alarming initial reports

The first studies of IHCA in COVID-19 patients — both from Wuhan, China where the virus was first detected, as well as from the United States — suggested dramatically and disconcertingly lower-than-average survival rates.

The following survival and return-of-spontaneous-circulation (ROSC) data covers COVID-19 patients who experienced in-hospital cardiac arrest and received CPR:

• Wuhan initial report — 136 patients: Only 13.2% achieved ROSC and 30-day survival was just 2.9%.³
• U.S. initial report — 31 patients: 65% achieved ROSC but none survived to hospital discharge.⁴
• Report from Michigan, March – April 2020 — 54 patients: 54% achieved ROSC but none survived to hospital discharge.⁵
• Data from Georgia, March – August 2020 — 63 patients: 29% achieved ROSC but none survived to hospital discharge.⁶

These studies caused many healthcare institutions to question whether they should be attempting to resuscitate COVID-19 patients at all. Were they needlessly forcing patients to endure the stress of chest compressions in the inevitable last moments of their lives? Were they subjecting clinicians to the higher risk of contracting COVID-19 while performing CPR for no reason? Some healthcare systems even considered implementing a universal do-not-resuscitate (DNR) order for COVID patients.^7,8

Glimmers of hope

Fortunately, several more studies were published that provided reason to believe that perhaps IHCA wasn’t a death sentence for every COVID-19 patient.

Two larger studies from the U.S. — one with 400 patients and another with 260 — reported 12% survived to hospital discharge. Of course this is still roughly half the pre-pandemic national average, but it’s certainly better than zero and indicates improvement is possible.^9,10

Even more promising, a retrospective study from March through October 2020 at Cleveland Clinic Hospital System (CCHS) showed that of 58 patients, 60.3% achieved ROSC and 22.4% survived to hospital discharge — right in line with pre-pandemic survival rates.¹¹

Discrepancy Analysis: A closer look at outcome variability

Even when we dive into the data for each of these studies, reasons for such drastic differences in survival rates for COVID-19 patients experiencing IHCA are not readily apparent. For example, clinical characteristics of the patients in each study were very similar: 

• Initial arrest rhythms were typically nonshockable.
• The majority of patients were on ventilators.
• Neither age, gender, race, ethnicity, BMI, comorbidities, or disease severity predicted better outcomes or improved survival.

So what factors could have come into play?

Human bias

First, let’s look at the CCHS study. Implicit bias could have motivated the study team to advise the sickest patients or surrogates against resuscitation, keeping those most at risk of death from appearing in the study at all.¹¹

Studies that demonstrated lower survival rates may have been contending with a different set of biases. After learning about published data suggesting COVID patients are less likely to survive IHCA — and more likely to infect healthcare workers due to the forceful expulsion of respiratory droplets during chest compressions — clinicians may have developed^3-6,12:

• Implicit bias toward earlier termination of CPR and other life-sustaining therapies
• More interest in pursuing a DNR status and comfort measures

Time

After the initial spread of COVID-19 in the U.S., best practices and strategies for treating the disease evolved and new therapies were developed. Even before vaccines were available, clinicians were able to optimize their approaches to treating COVID patients, resulting in many hospital systems getting a better handle on the disease over time.

This may be one reason for the higher survival rates in the CCHS dataset, as it covers a longer period of time than the other studies.

Hospital-specific factors

Several institution-level factors also likely contributed to the discrepancies in reported survival rates, including^13-16:

• Variations in COVID-19 management protocols
• Accessibility of COVID-19–specific therapies
• Availability of resources for personnel-intensive therapies such as proning 
• Number of ICU beds and trained critical care professionals on staff 

This last point is particularly important, as initial disease surges put major strain on many hospitals and healthcare systems. For example, the incidence of IHCA on medicine wards was higher than usual and even higher than in the ICU. ICU beds were scarce and trained critical care staff stretched thin, often resulting in shorter duration of CPR.

Notably, CCHS has one of the highest numbers of ICU beds in the country and plentiful critical care staff, which may have enabled them to maintain a higher standard of care throughout initial surges.

Key Takeaways: Promoting increased IHCA survival in COVID-19 patients

Based on what we know and can extrapolate from these early reports, there are a few steps that hospitals can take to pursue improved in-hospital cardiac arrest survival in patients with COVID-19.

1. Be prepared. COVID-19 waves and surges continue to impact communities across the country. Hospitals must keep an eye on trends and hire or take on freelance clinicians ahead of the curve to keep medicine and ICU wards from being overwhelmed.¹⁷ 

2. Prioritize clinician safety. To avoid some of the implicit bias issues discussed above and prevent the spread of disease that might further stretch resources, hospitals should take precautions to protect healthcare workers. Start by following the American Heart Association’s interim guidelines on COVID-19 IHCA management, including^12,18-20:

• Reducing provider exposure by ensuring personal protective equipment (PPE) is always available and accessible
• Limiting the number of healthcare professionals in the room
• Prioritizing resuscitation tools with lower aerosolization risk, such as HEPA filters, cuffed tubes, video laryngoscopy, and mechanical CPR

3. Practice, practice, practice. Train all providers to don PPE quickly, as each minute of delay in CPR can lead to a 7 – 10 percent drop in successful IHCA outcomes.^16,21