An Observational Analysis of EMS Calls for Out-of-Hospital Cardiac Arrest and Psychiatric Complaints During the COVID Pandemic

Summary

The first wave of the COVID-19 pandemic coincided with a profound decrease in emergency department (ED) visits.¹ This trend was also observed in medical calls for prehospital/EMS providers.² Though it will take time to fully understand the multifactorial etiology of this trend, this study sought to clarify two questions during the initial surge:

1. Did more patients suffer out of hospital cardiac arrest (OHCA) prior to seeking care?
2. Were there more 911 calls for psychiatric complaints (PCs)?

This observational analysis considered 911 call volume during the first three months of the COVID-19 pandemic (March, April, and May) for six major EMS providers in a suburban, midwestern EMS system and compared them with the previous year.

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While overall call volume during this three month period decreased by 13.6%, both the number and proportion of calls for OHCA increased (114 OHCAs/2,846 total calls in 2020 versus 78 OHCAs/3,293 total calls in 2019). This effect was most pronounced in April. It has been proposed that decreased access to primary care as a result of COVID-19 restrictions and fear of contracting the virus kept many patients and families from activating 911.

Background

This study took place at a suburban midwestern EMS system where medical direction is provided by a central resource hospital. The system contains nine separate EMS agencies: eight that are fire-based and provide 911 response and one that is private and performs interfacility transportation. The 911 providers responded to a total of 17,215 medical calls in 2019 and store patient care information on two independent electronic medical records (EMRs): Zoll Hosted³ and ESO Electronic Health Record.⁴ Six of the eight fire/EMS agencies who provide 911 service utilize the Zoll Hosted EMR, which accounts for 77% (13,190/17,215) of annual calls.

Methods

This study limited data to EMS responses documented in Zoll Hosted in order to control for terminology and categorization across multiple fire/EMS departments. The system was queried for all 911 EMS calls with patient contact by type (“Primary Impression”), fire/EMS service, and month for March, April and May of 2019 and 2020. Primary impression is the patient’s chief complaint, as observed by the provider and is chosen from a list of predetermined options. The Zoll Hosted EMR does not allow for multiple primary impressions.

OHCA included two primary impressions: “cardiac arrest” and “death on arrival.” These two groups are similar and mean that the patient was evaluated by EMS and found to not be conscious, be breathing or have a pulse. However, patients deemed death on arrival typically do not receive subsequent resuscitative efforts due to obvious signs of death (rigor mortis, decapitation, significant dismemberment). The two primary impressions were reported in aggregate and can include any cause or disposition.

PCs included many primary impressions (listed below) and sought to adequately capture the breadth of mental health emergencies, behavioral complaints, acute intoxication, and withdrawal states.

Antidepressant Abuse

Cocaine Abuse          

Delirium (Excited)      

Hallucinogen Abuse   

Inhalant Abuse           

Intoxication (Alcohol) 

Mental Disorder         

Opioid Abuse 

Sedative/Anti-anxiety Abuse 

Suicide Attempt          

Withdrawal Symptoms

OHCAs and PCs for March through May of 2020 were totaled by category, month and fire/EMS service, and compared with 2019. These values were also compared versus total number of EMS calls with patient contact over the same time period.

Results

Considering the initial questions

• Did more patients suffer OHCA prior to seeking care?

Total call volume decreased during the three month period in question; however, the total number of OHCA increased both in number and percentage of total calls (Table 1). This increase was most pronounced in April (51 in 2020 vs 19 in 2019) and was followed by a slight decrease in May (32 in 2020 vs 41 in 2019) as depicted in Figure 1.

March – May	2019	2020
Total OHCA	78	114
Total EMS Calls with Patient Contact	3,293	2,846
% Mix	2.4%	4.0%

• Were there more 911 calls for psychiatric complaints?

Calls for PC decreased versus year prior in both number and percentage of calls for the time period in question (Table 3). Additionally, unlike OHCA, PCs were uniformly decreased by month with minimal variability, ranging from a 21-29% decrease (Figure 4).

March – May	2019	2020
PCs	322	240
Total EMS Calls with Patient Contact	3,293	2,846
% Mix	9.8%	8.4%

Discussion and Limitations

This study shows that although overall EMS call volume decreased, the number and percentage of OHCAs increased during the first wave of the COVID pandemic. While contrasting, these two findings may be the result of similar factors.

In the early months of the pandemic when testing and PPE were scarce, many Americans were especially concerned that they could contract COVID-19 by engaging with healthcare. In addition, as non-emergent healthcare clinics closed, many of the previous outlets for primary care were no longer available. This may have led to patients no longer receiving the care necessary to effectively manage their complex conditions.

Finally, many received messages in the news and social media urging them to avoid overwhelming hospitals for non-emergency complaints. Unfortunately, it can be difficult for patients to discern emergent versus non-emergency complaints without actually seeking evaluation and advice from healthcare providers. 

It is interesting and unexpected that calls for psychiatric emergencies decreased during the first wave of the pandemic, as previous studies have demonstrated increased rates of anxiety and depression.^5,6 However, the same fears and pressures discussed above likely affected those suffering from psychiatric emergencies. Additionally, the most severe cases of psychiatric illness resulting in cardiac arrest are categorized as OHCA instead of PC.

Applicability of Early Pandemic Data

The pandemic has persisted for many months past the initial “surge” and has resulted in many new waves of infections.⁷ These findings hope to inform both consideration of past behavior and planning for future states.

Single Versus Multiple EMR Programs

There are inherent limitations when considering subsets of individual EMS systems. However, the use of multiple EMRs prevented consistent analysis of the entire system. Zoll Hosted EMR was selected because it represents the majority of departments and 911 call volume. Utilizing multiple EMRs risked inconsistency in terminology regarding primary impression and disposition. Trends were appreciated by maintaining consistency in the datasets for analysis.

In order to compare patient characteristics by agency, census data was reviewed by township. Six of the eight fire/EMS services serve distinct areas measured by the U.S. Census.⁸ The remaining two are reported in aggregate with other agencies serving their respective townships.⁹

Primary Impression

Providers who identify a patient as OHCA are often unaware of the actual cause of death or cardiac arrest. Even if the cause is evident, the primary impression options in this study do not subdivide “death on arrival” or “cardiac arrest” into causes. Acknowledging these limitations, this study aimed to include all deaths, regardless of the cause.

Additionally, while cardiac arrest and death on arrival are unique presentations in concept and are separated within the EMR primary impression, chart review has shown these two terms are sometimes used interchangeably when documenting OHCA. For this reason, rates of cardiac arrest and death on arrival were reported only in aggregate.

Disposition

EMS calls included in this study were not evaluated for disposition. Therefore, rates of morbidity, mortality and field termination were not included and may differ when considering 2020 versus 2019.

Call Location

All EMS call locations were included in this study (residential, industrial, commercial and roadway). Limitations in data retrieval made it infeasible to accurately isolate residential calls. Even though OHCA traditionally occur at home, analyzing all call locations allowed for better inclusion of undomiciled patients and PCs.

Monthly Variations

While the overall trend in OHCA is clear for the three month time period in question (46% increase versus year prior), there is notable variability when considering March and April versus May.

One explanation is the high rate of OHCA in May of 2019 (41 versus 18 in March and 19 in April of 2019). Research into the exact cause of this increase fell outside the scope of research; however, it demonstrates the value of several years of data for comparison.

Additionally, when considering the month by month trend of OHCA for March through May 2020 (31, 51, 32 for March, April, and May, respectively), there is a similar trend seen in national EMS call data.¹⁰ Lerner et al. demonstrated similar trends using the National Emergency Medical Services Information System (NEMSIS) database with the percentage of EMS activations for death on scene increasing in March from a baseline of ~1.2%, peaking in the second week of April at 2.4%, and decreasing during the month of May. However, the data presented by Lerner et al. at no point decreases versus year prior, further supporting the suspicion that OHCA in May of 2019 were unusually high.

Regionality

The pandemic has demonstrated considerable variability by region. During the study time period, Illinois exceeded the cumulative number of COVID-19 cases and deaths per 100K versus the total US (949 vs 538 Cases, 42.5 vs 31.5 Deaths).¹¹ Additionally, the trends noted in decreased ER visits as reported by the CDC are nationwide, and Illinois demonstrates similar losses as a member of Region 5.¹²

Suicide Fluctuation During Times of Crisis

Great attention has been paid to suicide during times of crisis, whether man-made or natural disasters. Emile Durkheim first presented the concept of decreased rates of suicide during wartime in 1897, proposing that greater social integration decreased suicidality.¹³ While this association was later refuted by Marshall in 1981, Durkheim presented a framework by which to consider two key environmental factors – societal regulation and social integration.^{14, 15}

These elements continue to play a role in our current climate with increased social integration uniting against a common cause, as well as increased societal regulation in order to limit the spread of COVID-19.

Implications

Recognizing that there were fewer EMS calls overall, but more calls with OHCA, prehospital providers must be prepared to meet patients in greater extremis. Patients with complex medical conditions, often well known to local EMS, may present more decompensated than previously seen. Prehospital providers should also be prepared for patients who are highly skeptical of interacting with healthcare due to fear of contracting the virus.

Additionally, EMS providers may encounter fewer psychiatric emergencies. This study did not evaluate the severity of the remaining PC, but preparedness for more severe presentations may benefit both patient and provider. Those suffering from psychiatric illness face the same limitations and fears as other members of the community with complex medical conditions.

Conclusion

The COVID-19 pandemic has had a profound impact on emergency healthcare. Patients and providers alike are learning to cope with an ever-changing landscape of limited resources, questions of safety and fear of presenting to care.

By considering EMS activations in a suburban midwestern EMS system, this study identified an increase in OHCA from March through May 2020 versus year prior and a decrease in psychiatric complaints during the same time period.

These trends in EMS activations during the first wave of the COVID-19 pandemic aim to help providers, healthcare organizations, municipalities, and policy-makers understand the implications of delayed medical care when patients are fearful of exposing themselves to a novel infectious agent. 

References

1. Hartnett KP, Kite-Powell A, DeVies J, Coletta MA, Boehmer TK, Adjemian J, Gundlapalli AV. Impact of the COVID-19 Pandemic on Emergency Department Visits – United States, January 1, 2019-May 30, 2020. MMWR Morb Mortal Wkly Rep. 2020 Jun 12;69(23):699-704. doi: 10.15585/mmwr.mm6923e1. PubMed PMID: 32525856; PubMed Central PMCID: PMC7315789.

2. Lerner EB, Newgard CD, Mann NC. Effect of the Coronavirus Disease 2019 (COVID-19) Pandemic on the U.S. Emergency Medical Services System: A Preliminary Report. Acad Emerg Med. 2020 Aug;27(8):693-699. doi: 10.1111/acem.14051. Epub 2020 Jul 7. PubMed PMID: 32557999; PubMed Central PMCID: PMC7323429.

3. Systems, ZOLL Data. ZOLL Data Systems: EMS, Fire, Hospital, and AR Optimization Software, www.zolldata.com/.

4. “Electronic Health Records for Emergency Services.” ESO, www.eso.com/ems/ehr/.

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6. Brooks SK, Webster RK, Smith LE, Woodland L, Wessely S, Greenberg N, Rubin GJ. The psychological impact of quarantine and how to reduce it: rapid review of the evidence. Lancet. 2020 Mar 14;395(10227):912-920. doi: 10.1016/S0140-6736(20)30460-8. Epub 2020 Feb 26. PMID: 32112714; PMCID: PMC7158942.

7. “CDC COVID Data Tracker.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, Accessed 7 Feb. 2021, covid.cdc.gov/covid-data-tracker.

8. “U.S. Census Bureau QuickFacts: Summit Village, Illinois; Oak Lawn Village, Illinois; Chicago Ridge Village, Illinois; Burbank City, Illinois; Bridgeview Village, Illinois; Stickney Village, Illinois.” Census Bureau QuickFacts, www.census.gov/quickfacts/fact/table/summitvillageillinois,oaklawnvillageillinois,chicagoridgevillageillinois,burbankcityillinois,bridgeviewvillageillinois,stickneyvillageillinois/PST045219.

9. “U.S. Census Bureau QuickFacts: Summit Village, Illinois; Oak Lawn Village, Illinois; Chicago Ridge Village, Illinois; Burbank City, Illinois; Bridgeview Village, Illinois; Stickney Village, Illinois.” Census Bureau QuickFacts, www.census.gov/quickfacts/fact/table/summitvillageillinois,oaklawnvillageillinois,chicagoridgevillageillinois,burbankcityillinois,bridgeviewvillageillinois,stickneyvillageillinois/PST045219.

10. Lerner EB, Newgard CD, Mann NC. Effect of the Coronavirus Disease 2019 (COVID-19) Pandemic on the U.S. Emergency Medical Services System: A Preliminary Report. Acad Emerg Med. 2020 Aug;27(8):696, Figure 2. doi: 10.1111/acem.14051. Epub 2020 Jul 7. PubMed PMID: 32557999; PubMed Central PMCID: PMC7323429.

11. “CDC COVID Data Tracker.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, covid.cdc.gov/covid-data-tracker/#compare-trends_totalcasesper100k.

12. Hartnett KP, Kite-Powell A, DeVies J, Coletta MA, Boehmer TK, Adjemian J, Gundlapalli AV. Impact of the COVID-19 Pandemic on Emergency Department Visits – United States, January 1, 2019-May 30, 2020. MMWR Morb Mortal Wkly Rep. 2020 Jun 12;69(23):701, Figure 2B. doi: 10.15585/mmwr.mm6923e1. PubMed PMID: 32525856; PubMed Central PMCID: PMC7315789.

13. Durkheim E (1897). Suicide: A Study in Sociology. The Free Press: New York.

14. Marshall JR (1981). Political Integration and the effects of war on suicide: United States, 1933–76. Social Forces 59, 771–785.

15. Devitt P. Can we expect an increased suicide rate due to Covid-19? Ir J Psychol Med. 2020 Dec;37(4):264-268. doi: 10.1017/ipm.2020.46. Epub 2020 May 21. PMID: 32434598; PMCID: PMC7287306.