Abstract
Background
In emergencies, such as the COVID-19 pandemic, there is an increased need for contact with emergency medical services (EMS), and call volume might surpass capacity. The Copenhagen EMS operates two telephone line the 1-1-2 emergency number and the 1813 medical helpline. A separate coronavirus support track was implemented on the 1813 medical helpline and a web-based self-triage (web triage) system was created to reduce non-emergency call volume. The aim of this paper is to present call volume and the two measures implemented to handle the increased call volume to the Copenhagen EMS.
Methods
This is a cross sectional observational study. Call volume and queue time is presented in the first month of the COVID-19 pandemic (27th of February 2020 to 27th of march) and compared to the equivalent month from the year before (2019). Descriptive statistics are conducted on call volumes and queue times and spearman’s rank correlation test are performed to test correlation between web triage and call volume.
Results
Total EMS call volume increase by 23.3% between 2019 and 2020 (92.670 vs. 114,250). The 1-1-2 emergency line total call volume increase by 4.4% (8,4942 vs. 8,870) and the 1813 medical helpline increased by 25.1% (84.176 vs. 105.380). The coronavirus support track handled 21,063 calls. The 1813 medical helpline queue time was a mean of 02 minutes and 23 seconds (CI: 2.22-2.25) in 2019 and 12 minutes and 2 seconds (CI 11:55-12:09) in 2020 (P < 0.001). The web triage was used 10,894 times. No correlation between call volume and web triage usage was seen.
Conclusions
In the first month of the ongoing COVID-19 pandemic a significant increase in call volume was observed in the 1813 medical helpline compared to 2019. A large number of calls were handled by the additional coronavirus track and diverted away from the regular tracks of the 1813 medical helpline. This likely contributed to mitigating increased call volumes and queue times. The web triage was widely used but no significant correlation was seen with 1813 medical helpline call volume. Other EMS organizations can learn from this to enhance capacity in a future epidemics.
Background
On March 11, 2020, coronavirus disease 2019 (COVID-19) was categorized as a pandemic by the World Health Organization (WHO) (Citation1). In such emergencies, it is vital for citizens to be able to contact emergency medical service (EMS) (Citation2). Based on previous events, the EMS will witness a dramatic increase in call volume and consequently have reduced availability. Such a surge lead to increased line queues, missed calls, delayed EMS or hospital responses and psychological barriers that lead callers to avoid contact (Citation3–5). In addition, attempts to limit transmission using effective rapid triage systems are adversely affected if callers are forced to wait for extended periods. It is argued that rapid and frequent adaptations from the prehospital EMS is warranted (Citation6). The triplication of call volume observed at the beginning of the COVID-19 EMS burden in Italy February indicated what could be expected elsewhere (Citation7). Similarly, an increase in 9-1-1 call volume have been witnessed in the United States of America during the early part of the COVID-19 impact, although at same time a decrease in the number of EMS activations compared to the prior same time period in previous years (Citation8).
On February 27, 2020, the first case of COVID-19 (indicator patient) was confirmed in Denmark, and the first COVID-19-related hospitalization was confirmed on March 9. One month later (March 27, 2020), Denmark had 430 individuals hospitalized (23 per 100,000 inhabitants), 109 individuals in intensive care departments (6 per 100,000 inhabitants), and 52 deaths (3 per 100,000 inhabitants) due to COVID-19. Approximately half of the confirmed cases were in the Capital Region of Denmark (Citation9).
The Danish EMS system is organized into five regions with similar structures serving ambulances, physician staff vehicles and emergency medical dispatch centers (EMDC) (Citation10). The Capital Region of Denmark, Copenhagen, has 1.8 million inhabitants served by the Copenhagen EMS. The Copenhagen EMS is an integrated health care service comprised of an emergency medical dispatch call center, ambulance service and physician- and paramedic-staffed mobile critical care units. The Copenhagen EMS is accessed through two main numbers, the 1-1-2 (the European emergency number) for life-threatening emergencies and the 1813 medical helpline for all other urgent medical issues, including access to emergency departments. Both lines manage and triage all urgent hospital admissions and as gateway to all hospital contact central components of the health care system. The 1813 medical helpline receives approximately 1,800 calls on weekdays and 3,500 calls daily on weekends and is constantly staffed by approximately 25 nurses and physicians. Each caller is triaged to either advice, admission to the emergency department (including booking a time slot), direct hospitalization, dispatch of ambulance response or home-visit by a physician.
The Danish EMS system is the gateway to Danish hospitals and emergency departments, and a potential increase in call volume may indirectly result in increased mortality caused by delayed or erroneous responses to critical emergencies. Therefore, measures are needed to reduce call volume without restricting the general public’s access to essential rapid triage and counseling with respect to the ongoing pandemic. Hence, it makes sense to consider alternative methods of disseminating information to people with mild or no relevant symptoms and to those who are concerned or are seeking more general advice, without causing excessive increases in call volume to the vital EMS.
Previous strategies include installation of nationwide nurse-staffed telephone triage lines, with the aim of reducing the increased demands for health care advice and assessment during a pandemic. Such measures were successful in triaging callers and providing clinical advice, including information about ongoing flu pandemics (Citation6,Citation11,Citation12). During the wake of the current COVID-19 pandemic, the Copenhagen EMS implemented a system aimed at diverting mild COVID-19-related calls to the EMS. When calling the regional medical helpline, the call was directed either into the normal track or to a specific helpline operated by additional healthcare-educated staff, thus unlocking resources on the main track for serious illness. The system was implemented with the ability of dispatcher to divert calls and was changed so that callers forwarded themselves to the coronavirus support track on March 9, 2020. Hence, all callers in the time was asked to choose the normal helpline or the coronavirus support track when calling the 1813 medical helpline.
Another strategy is the implementation of a web-based self-triage system (henceforth regarded to as” web triage”). The web triage is an internet survey posing as a test of key symptoms, resulting in a rough triage of the necessity of calling EMS. Similar systems have successfully been used for comparable symptomatic manifestations surrounding an influenza pandemic (Citation13,Citation14).
Aim
The aim of this paper is to present the call volumes to the EMS, queue times and coronavirus support track and the web-based self-triage of mild COVID-19 symptoms. Furthermore, this paper aims to examine the potential effect of these initiatives on reducing non-essential EMS call volume and EMS queue time in the ongoing pandemic. This allows other EMS systems to learn from the Copenhagen experience to enhance capacity in times of sparse healthcare resources.
Method
This investigation is a cross sectional observational study examining the effect of implementing a coronavirus support track and web triage on EMS call volume.
The Coronavirus Support Track
The support track was launched, as a separate queue system within the 1813 medical helpline and was established as a stand-alone center on March 9. The track could only be reached by those calling the 1813 medical helpline and no separate phone number was available.
The support track was staffed by 5-18 persons at peak, all with a healthcare-related educational background (e.g., nurses, medical students, medical doctors). The staff was instructed to follow a protocol resulting in the algorithmic placement of responses (). The caller could eventually be given advice on actions or self-isolation or be directed to the emergency EMS track for triage.
Figure 1. Flowchart for the coronavirus support track.
All callers who contacted the 1813 medical helpline were presented with the option to either go to the coronavirus support track if they were calling concerning COVID-19 or continue to the normal EMS if their call concerned other emergent medical issues (). All calls regarding life-threatening emergencies were still directed to call the 1-1-2 emergency line.
Development of the Web-Based Self-Triage System
The development of the web triage was initiated on March 12, and the system was ready to launch only three days later. A simple algorithm based on the triage of potential COVID-19-infected patients () was designed and implemented as an online web application for inclusion on the already-established Copenhagen EMS webpage and initiated on March 15.
Figure 2. Flowchart for the initial web-based self-triage system.
Dissemination of the Coronavirus Support Track and the Web Triage
Awareness of the web triage and the coronavirus support track was initially disseminated to the public through a press release by the Copenhagen EMS, the Capital Region and the websites and social media channels (Twitter® and Facebook®) of hospitals in the region.
Data Collection
Data were collected from February 26, 2020, to March 27, 2020, for all calls to the 1-1-2 emergency line and 1813 medical helpline. The data are stratified by the access number used, i.e., the 1-1-2 emergency line and 1813 medical line and the coronavirus support track.
Call handling data were obtained from the Copenhagen EMS call center audit database. All calls were extracted and could be discriminated by the caller’s choice of staying in queue for the 1813 medical helpline or actively choosing the coronavirus support track by pressing 1. The Copenhagen EMS call center audits database contains detailed information on the call eg. queue time, call length and talk-time. Queue-time was defined at starting once the caller entered the correct line, eg. pressed 1 and entered the corona medical helpline, and queue-time ends once the call handler greets the caller. The database is linked to the medical report system, in which all information on the patient and the response given to the incident are stored. Data regarding daily usage and development phases of the web triage were obtained by the Copenhagen EMS from Microsoft® Denmark. Data regarding caller demographics and referrals were obtained by the Copenhagen EMS dispatch system.
To adjust for the leap year in 2020, data was collected on calls for 31 consecutive days from February 26 for both years, thus ending data collection on march 28 2019 and March 27 2020.
Statistics
Descriptive analyses were performed. Absolute numbers and percentages for variables were reported. Comparative analyses were performed using chi-square tests and Student’s t-tests. A calculation was performed using ANOVA for the comparison analysis. To test for assumptions of normal distribution Shapiro-Wilk normality test was conducted for all variables with null-hypothesis that data are not significantly different from normal distribution. Either Pearson’s R or Spearman’s Rank correlation test between web triage, 1813 medical helpline call volume (both normal track and coronavirus support track) was conducted depending on distribution. Data is stratified by days.
Analysis was performed using R. Version 3.2.0 (R Foundation for Statistical Computing, Vienna, Austria).
Ethics
We followed the General Data Protection Regulation and registered the study with the Danish Data Protection Agency (journal number P-2020-343). The study was approved by the Danish Patient Safety Authority (journal number 31-1521-267). The Research Ethics Committee in the Capital Region of Denmark waived the need for ethical approval (journal number 20026743).
Results
The Danish health care authorities observed a steep rise in the number of confirmed cases, with a daily doubling in the number of cases from March 8-11. On March 12, the strategy officially changed from containment and suppression to mitigation and preparation. On March 14, the first official mortality due to COVID-19 was confirmed. Neither call volume data from the medical helpline nor data from the web triage data was normally distributed when tested with Shapiro-Wilk normality test (call volume medical helpline 2019, P > 0.001, call volume medical 2020, P = 0.003; call volume data from coronavirus support track, P = 0.004 and web triage data, P > 0.001). Hence test of correlation was conducted using the Spearman’s Rank test.
EMS Call Volume
The EMS 1-1-2 emergency line received 8,870 calls in 2020 compared to 8,494 in 2019. There was a difference in the age of the callers (a mean of 53.0 years in 2020 and a mean of 53.6 years in 2019). The normal (non-coronavirus) 1813 medical helpline tracks received 84,317 in 2020 compared to 84,176 in 2019 () from February 27 until one month after. No increase in the EMS call volume for the normal (permanent) 1813 medical helpline tracks (excluding the coronavirus support track) was observed from the first confirmed case in Denmark on February 27, 2020, until one-month later March 27, 2020, when compared to 2019. There was no apparent difference in the relative distribution of call volume by day or day of the week (). However, since the introduction of the coronavirus support track on March 4, 2020, a large number of calls to the EMS were forwarded to the specific coronavirus support track. The coronavirus support track received a total call volume of 21,063 calls in this period () and had mean queue times of 13 minutes and 46 seconds (). Hence, the overall call volume to all 1813 medical helpline tracks (all standard tracks and the coronavirus support track) was 105,380 calls. Overall calls volume for Copenhagen EMS was hence increased by 24% in the period when all tracks are considered together. The difference in overall call volume between 2020 and 2019 when all tracks are considered together was significant (P < 0.001).
Table 1. Demographics of EMS calls from February 27 to March 27, 2020
The call volume on the coronavirus support track peaked on March 12, with approximately 2,100 calls in one day. Furthermore, 4,409 (20.9%) of the calls to the coronavirus support track was redirected to regular 1813 medical helpline tracks; these calls were to be further assessed and triaged by a physician.
Hence, in total, a significant (P < 0.001) increase in the total EMS call volume was observed, most extensively from March 2-15 but was mitigated by the implementation of to the coronavirus support track (). After day 19 (March 15), a minor decrease in total call volume was witnessed on both the 1813 medical helpline and the specific coronavirus support track ().
Figure 3. Accumulated call volumes and web-based self-triage system use.
Call volume [number of calls] for the 1813 medical helpline, the 1-1-2 emergency line and the COVID helpline from February 26 to March 27, displayed for 2020 and 2019. Dates does not match between 2019 and 2020 as 2020 was a leap year.
![Figure 3. Accumulated call volumes and web-based self-triage system use.Call volume [number of calls] for the 1813 medical helpline, the 1-1-2 emergency line and the COVID helpline from February 26 to March 27, displayed for 2020 and 2019. Dates does not match between 2019 and 2020 as 2020 was a leap year.](/cms/asset/7694b724-d016-482a-9077-9d74d9364e20/ipec_a_1817212_f0003_c.jpg)
EMS Queue Time
Although call volume was seemingly not substantially higher once the capacity was overloaded, the EMS queue time is the first marker and will rise steeply. The limited capacity of the EMS 1813 medical helpline was seen to be significantly overloaded in this period, with significantly higher queue time than in 2019. In 2020, the mean queue time was 12 minutes and 2 seconds (CI: 11:55-12:09), which is significantly (P < 0.001) higher than the two minutes and 23 seconds (CI: 02:22-02:25) observed in 2019 (). Several periods with a maximum queue time of up to 2 hours was noted in the very peak of the corona burden prior to implementation of the coronavirus support track.
Several peaks in queue time were notable on the EMS 1813 medical helpline, most notably on March 1, 8-9, 11-12 and 15 (Day 4, 11-12, 14-5 and18 in ). The calls forwarded to the coronavirus support track had a similar peak pattern after the implementation, except for the initial peak on March 1 prior to implementation (). The increase in queue time was due to not only an increase in call volume but also an increase in time for call handling (conversations are longer by approximately 1 minute).
Figure 4. Queues for EMS lines and key events around the Danish COVID-19 impact.
Day 1: February 26 in both 2019 and 2020. 2020 was a leap year, and hence, comparable dates cannot be displayed for both years. The first COVID-19 patient was confirmed on February 27, 2020. The coronavirus support track was initiated on the March 4, 2020. The lockdown of Denmark was announced on March 11 and initiated on March 13. The first fatality due to COVID-19 was confirmed on March 14, 2020. An official mailing with a description of symptoms was sent to all Danish citizens on March 20, 2020.
Several events coincide with peaks in queue time, notably a slow peak in queue time in the days after the announcement of the first confirmed patient (see ).
Use of the Web Triage
The web triage was implemented on March 15 and was included on the Copenhagen EMS webpage. In the first month, the web triage was used 107,894 times. A total of 92.2% of users completed all questions on the web triage, and 14.6% marked that they had respiratory distress ().
Table 2. Demographics of web-based self-triage system users
A total of 24,883 users provided information and feedback for the system. Among the users agreeing to provide feedback, 80% found the system satisfactory, and 20% did not. The median age for users was 42 (IQR 31-54), with more female users (59%). The web triage had more users in the daytime than at night. Of the three possible types of advice that could be offered, the web triage advised 24.0% (21,186 calls) of users that they had reported symptoms of COVID-19, 35.3% (31,112 calls) of users were advised to self-isolate, and 40.7% (35,956 calls) were advised to call the EMS and coronavirus support track. Spearman’s Rank test for correlation between usage of the web triage and all 1813 medical helpline calls in the first month found no significant correlation (rho = −0.212; P = 0.2518). Spearman’s Rank test for correlation between usage of the web triage and coronavirus support track in the first month found no significant correlation (rho = 0.275; P = 0.135).
Discussion
Main Results
This study found increasing call volume to the 1813 medical helpline during the beginning of the national COVID-19 pandemic. The queue time for the 1813 medical helpline increased markedly during the first month of the impact of COVID-19 in Denmark to a mean of 12 minutes and 2 seconds in 2020, compared to an average of 2 minutes and 23 seconds in 2019. However, the impact was drastically reduced using a specific healthcare-staffed coronavirus support track to forward all calls regarding the ongoing pandemic. In peak periods, the coronavirus support track had a call volume that was similar to that of the EMS 1813 medical helpline and thus relieved the burden; the 1813 call volume returned to operating capacity after the burden was cut almost in half.
Using a Target Healthcare-Staffed Support Track to Relieve the EMS Burden
In 2009 a nurse-staffed and American-based flu support track created by the Centers for Disease Control (CDC) had the same aim of reducing call volume to the EMS (Citation11). One of the unresolved questions in the publication hereof was whether the alternative call lines played a prominent role in a pandemic response to meet patients' needs and reduce the surge in healthcare facilities (Citation11). In Copenhagen, the coronavirus support track managed almost the same number of calls as the EMS in the peak of the surge around March 11. Without the coronavirus support track, the EMS would have been overwhelmed with an extensive line queue and, consequently, potential missed calls and delayed EMS or hospital responses, possibly leading to psychological barriers that cause callers to avoid contact.
Web Triage
Another measure to reduce the strain on the EMS that differs from the CDC flu line was the establishment of the web triage. The web triage was widely used with more than 107,000 users from its launch until March 27. However, no effect on call volume is indicated or documented. Users were mainly younger adults (median 44 years, IQR 31-54 years). The web triage was limited in interaction, and as expected, not all symptoms were presented; consequently, some potentially infected persons could have been missed (Citation1,Citation15,Citation16). The authors find that the web triage might run the risk of being too simple to be useful for some users (20%). Furthermore, without revisions, some citizens might not trust the answers due to the simplicity and rigidity of the first version. For subsequent updates and revisions, the authors find it relevant to examine user engagement (Citation17). However, the central merit of a user web triage is that it can be developed and implemented in a matter of days to provide instant relief for EMS lines and offer relevant advice to citizens who are not in need of triage or healthcare advice beyond self-isolation or a test of symptoms. We found that 85.4% of web triage entries presented with mild or no relevant symptoms, and a proportion of these entries could have potentially overloaded the EMS (accounting for up to 92,141 additional calls). A similar web triage created for the 2009 influenza pandemic was designed with an expert panel and several revisions and was furthermore based on recurrent data in hospitalizations (Citation13). The perspectives are explicitly to evaluate the effort and further develop an actual active “chatbot”. A “chatbot” is defined as an “artificial intelligence program designed to simulate human conversation via text or speech”, as opposed to the current flowchart model (Citation18,Citation19).
Costs and Alternatives
Acting on an emerging pandemic can be both costly and ineffective prior to initial evaluation and revision of efforts. Alternative strategies to consider is advising citizens with mild symptoms to call their general practitioner. However, this have some inherent disadvantages in contrast to integrating the response EMS. The EMS personnel would have direct access to triage and could forward the calls to relevant other tracks id needed. Further giving uniform answers is secured more easily when the staff is only handling corona related calls. The cost is comparatively lower as the line was staff with nurses and medical students in adjunction to the doctors.
Perspectives
The early detection of viral disease outbreaks prior to widespread endemics is necessary to initiate measures to limit the prevalence and mortality (Citation20,Citation21). Using additional helpline tracks and web triage for pandemics can help ease and alleviate the monitoring process by delivering low-cost intuitive and adaptable systems. Web-based systems provide increased transparency and may allow earlier detection of disease outbreaks at a reduced cost (Citation22,Citation23).
Strengths and Limitations of the Study
A strength of this study is the large amount of data and the richness of personal information of EMS users in Denmark in general. Another strength of the study is that the speed of the implementation of these emergent initiatives ensured reliable data in the very early phase of the EMS call surge. However, this study has also limitations, and the data must be interpreted with caution and used for inspiration. In contrast to a randomized trial, this study cannot assume that the callers and users of web triage would not call or use the web triage if these initiatives had not been communicated to the public. If public knowledge of these initiatives did indeed create the observed additional volume by implication of the public awareness of the initiatives, the effect is moderate at best. However, we find that very recent data from the Italian EMS present a situation in which call volume did rise threefold; hence, it is somewhat logical to expect the burden to be “real”.
Although a measure of correlation has been conducted in this study (Spearman rank test) there are no comparisons made determining the effect of the coronavirus support track or web triage (i.e., this is descriptive only). Furthermore, the data collected and presented on the web triage have several uncertain characteristics, including the inability to portray multiple uses by the same persons and whether users completed the web triage. Personal data regarding the users of the web triage was collected voluntarily after the usage of the web triage and is hence uncertain and has a high degree of missing values.
As such, the conclusions of this study on the effect of caller volume are severely limited by several potentially important uncontrolled factors.
Conclusion
In the first month of the COVID-19 pandemic in Denmark, the emergency medical dispatch center in Copenhagen was extensively overloaded, resulting in prolonged queue time and thereby limiting access to emergency help and triage for citizens. The Copenhagen EMS developed and implemented a coronavirus support track and a web-based self-triage system to reduce nonemergency call volume on the emergency medical dispatch centers. The introduction of the coronavirus support track showed reduced call volume and queue time to the EMS 1813 medical helpline. Other EMS systems can implement these emergent measures to enhance capacity and potentially use them as early warning tools to help monitor future epidemics.
Declarations
Ethics Approval and Consent to Participate
We followed the General Data Protection Regulation and registered the study with the Danish Data Protection Agency (journal number P-2020-343). The study was approved by the Danish Patient Safety Authority (journal number 31-1521-267). The Research Ethics Committee in the Capital Region of Denmark waived the need for ethical approval (journal number 20026743). All data was aggregated anonymous data and informed consent was not relevant in current study.
Consent for Publication
Not applicable
Availability of Data and Materials
Data are available upon reasonable request. Please email the corresponding author to request the relevant data. Please provide the authors of the article with a detailed protocol for the proposed study and supply information about the funding and resources to conduct the study. If appropriate, invite the original author[s] to participate in the re-analysis. If a month elapses without a response from the authors, please email the editorial office.
Competing Interests
None of the authors has a financial conflict of interest.
The Copenhagen Emergency Medical Services have received unrestricted research grants from the Laerdal Foundation. The TrygFoundation has supported a large number of projects. None of these occurrences has influenced data collection, data processing, or the analysis or interpretation of data.
Author Contributions
All authors agreed on the study setup, data collection and analysis. TJ, the first author, was involved in the data collection and drafted the manuscript along with MGH, MSJ, SNB and HCC. SNB performed all data processing and analysis. All authors were involved in the critical review of the manuscript.
| Abbreviations | ||
| COVID-19 | = | coronavirus disease 2019 |
| EMDC | = | emergency medical dispatch center |
| Web triage | = | web-based self-triage system |
| EMS | = | emergency medical services |
| WHO | = | World Health Organization. |
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