Characteristics of Out of Hospital Cardiac Arrest in the United Arab Emirates.

BACKGROUND: Out of hospital cardiac arrest is one of the leading causes of death globally. This study aimed to identify the characteristics of out of hospital cardiac arrest patients who were attended and treated by the National Ambulance crew. A lot of studies reported the importance of implementing chain of survival to increase survival rates from cardiac arrest. To be implemented in United Arab Emirates (UAE), it required a detailed study of the community engagement. The study aimed to explore the demography of the incidences, location, age, gender epidemiology of the patients who had their cardiac arrest witnessed along with their Bystander cardiopulmonary resuscitation (CPR) performed prior to the arrival of National Ambulance and public access to an automated external defibrillator. The return of spontaneous circulation was also explored prior to their arrival to the emergency department.
METHODS: The research is a prospective descriptive cohort study of out of hospital cardiac arrest patients attended by National Ambulance between July 2017 and June 2018. The National Ambulance provides emergency medical services for public and private hospitals in the Emirates of Sharjah, Ajman, Ras-al-Khaimah, Fujairah, and Umm Al-Quwain and its clients in Abu Dhabi in UAE. Data for the study were collected by the National Ambulance crew attending the OHCA patients, using a structured questionnaire.
RESULTS: In this 1-year period, a total of 715 out of hospital cardiac arrest cases were attended by the National Ambulance with higher percentage (77%) of male patients. Resuscitation and transportation were attempted for 95% whereas 5% were pronounced dead on the spot. In this study, the median age of the patients was 50 years. Majority of the patients were Asians 55% (n = 395) followed by Arabs non-UAE citizens 19.4% (n = 139) and UAE citizens 16% (n = 113). Patients facing sudden cardiac arrest in their homes or residences represented 69.9% (n = 500), street and public places 22.5% (n = 161), and workplace 6.8% (n = 49). The percentage of patients who had witnessed cardiac arrest was 51.7% (n = 370) only 197 had CPR performed on them prior to the arrival of National Ambulance. Low public access to AED was found in this population that is 1.8% (n = 13). A majority of the participants in this study had nonshockable rhythms 84.3% (n = 603) whereas shockable rhythms presented on 11% (n = 80). The percentage of patients who had ROSC at the scene or en route to the hospitals was found 9.2% (n = 66).
CONCLUSION: In this 1-year study, the result showed that cardiac arrest was recognized and witnessed in about half of the cases, but low bystander CPR was performed. Low public access and use of AED were found. Data on hospitalized and discharged OHCA patients were not available and required further linkage and corporation between ambulance services and hospitals to ensure data continuity of OHCA cases. This study is essential for the implementation of proper chain of survival and reduction in mortality rates in UAE. Copyright:

INTRODUCTION

Sudden cardiac arrest is a global concern, especially out of hospital cardiac arrest (OHCA). Although the percentage of the cardiac arrest cases has increased globally, the number of survival rate is still low.[1] Establishing OHCA registry has become very important for a lot of countries to enable them to understand the characteristics of this condition and to improve the survival rate.[2]

The limited number of studies about the characteristics of OHCA has been conducted in the Middle East, which is crucial to understand and implement strategies to reduce mortalities. In the United Arab Emirates (UAE), National Ambulance started its operation in 2010 to provide emergency medical services (EMS) in the Emirates of Sharjah, Ajman, Ras-al-Khaimah, Umm Al-Quwain, Fujairah, and Abu Dhabi private clients. A majority of the service is staffed by licensed emergency medical technicians and paramedics.[3]

All the emergency calls are received by Ambulance Communication Center (ACC) in Abu Dhabi. As the majority of the UAE population consists of expatriates, call takers speak either of the following spoken languages: Arabic, English, Hindi, Urdu, Filipino, French, Persian, and Bengali. The King County Criteria Based Dispatch is used by call takers to provide all required information based on clinical categories. This is used by ACC. Mobile application (NA998) is available to the users in UAE which enables them to request an ambulance online with their accurate GPS location. Users of this application receive a call from ACC after requesting an ambulance to assist them in emergency.

The National Ambulance is a member of the Pan Asian Resuscitation Outcomes Study (PAROS) which is a collaboration between academic centers and EMS agencies to evaluate OHCA cases in Singapore, South Korea, UAE, Taiwan, Japan, Thailand, and Malaysia.[4] The purpose of group studies is to monitor and evaluate all cardiac arrest cases.

Objectives

The aim of the study is to present and evaluate all OHCA cases attended and treated by the National Ambulance in UAE.

METHODS

Study design and ethical consideration

It was a prospective descriptive cohort study for all OHCA cases that were attended by the National Ambulance. It was conducted in all of Sharjah, Ajman, Ras-al-Khaima, Umm Al-Quwain, Fujairah, and Abu Dhabi private clients. Dubai is excluded from the study population because National Ambulance does not provide its services there. The study protocol and ethics were reviewed and approved by the ethics review committee in the National Ambulance.

Selection criteria and study questionnaire

All patients who met the definition of OHCA were included which reads “Any patient unresponsive with absent breathing or pulse outside the hospitals.” A specific PAROS questionnaire form was designed for this research and monitored by PAROS coordinator and clinical researcher in National Ambulance.

Data collection and statistical analysis

Data were collected by completing PAROS form through National Ambulance EMTs who attended and treated OHCA cases between July 2017 and June 2018. Collected data were statistically analyzed using SPSS version 21 (Statistical Package for Social Scientist, IBM, NYC, USA). Descriptive analyses, continuous variables, independent group t-test, and patients' characteristics were also completed.

RESULTS

During the study, a total of 715 OHCA cases were attended by National Ambulance crew enrolled in this study. Most of the victims were male 77% (n = 548) while 23% (n = 167) were female. It represents that males are in a higher proportion of OHCA than females, and approximately, there were four males for every female. The median age for the patients included in this study was 50 years, median 50.6, interquartile range [IQR]: 35, 65, and standard deviation ± 22.3. Missing dates of birth and ages were 4% (n = 30) and were excluded.

As the majority of the population in UAE are expatriates, Asians among them were found in the highest percentage in this study 55% (n = 395), followed by Arabs non-Emiratis 19.4% (n = 139). Europeans and Africans were found in the lowest percentage when compared to other nationalities. UAE nationals in this study were 16% (n = 113) of the total cases, and the majority of them were males 58.4% (n = 66). Participants with missing ethnicity information were 4% (n = 29) of the cases. From the total number of cardiac arrest victims, 23.3% (n = 167) had medical history of diabetes, followed by 20.6% (n = 148) who had a history of hypertension and 14.4% (n = 103) with medical history of heart diseases. More past medical conditions of the patients included in this study were described in Figure 1.

Figure 1

The past medical conditions among out of hospital cardiac arrest patients between June 2017 and July 2018

Table 1 shows the characteristics of the 715 OHCA cases attended by National Ambulance. The highest number of cases occurred in Sharjah 44% (n = 315) followed by Ajman 19% (n = 136). In Abu Dhabi, National Ambulance is not the primary EMS provider; therefore, in the study, Abu Dhabi had the lowest OHCA cases in the data that is about 1%. The data were collected and recorded by National Ambulance crew from private clients and contractors in Abu Dhabi. Other nationalities and locations are summarized in Table 1.

Table 1

Demographic of out of hospital cardiac arrest cases attended by National Ambulance between June 2017 and July 2018

OHCA	Population 715, % (Number)
Location in United Arab Emirates
Sharjah	44% (315)
Ajman	19% (136)
Ras-al-Khaimah	17% (124)
Fujairah	13% (93)
Umm Al-Quwain	6% (40)
Abu Dhabi contractors	1% (7)
Gender
Male	77% (548)
Female	23% (167)
Age
Mean	50 years
SD	22.3
Median (IQR)	50.6 (35,65)
Ethnicity
Asians	55% (394)
Arab	19.4% (139)
UAE citizens	15.8% (113)
Africans	3.2% (23)
Europeans	2.2% (16)
Unknown	4.1% (30)
Past medical history
Diabetes	23.3% (167)
Heart diseases	14.4% (103)
Hypertension	20.6% (148)
Cancer	2.7% (20)
Stroke	1.9% (14)
Location of the incident
Home	67.5% (483)
Streets and public places	22.5% (161)
Workplace	6.7% (48)
Healthcare centers	2.7% (20)
In the Ambulance	0.4% (3)
Respond time from call received to Ambulance dispatch	Minutes
Median	1.8
Respond time from Ambulance dispatch to scene arrival	Minutes
Median	11.2
Prehospital witnessed cardiac arrest
Witnessed arrests by Families, Bystanders layperson and healthcare providers	51.7% (370)
EMS	7.6% (55)
Not Witnessed	40.5% (290)
Bystander CPR	30.7% (220)
Bystander applied AED	1.8% (13)
First rhythm
shockable ( VF, VT, Unknown Shockable Rhythm)	12.5% (79)
Non shockable( PEA, Asystole, Unknown unshockable Rhythm)	83.2% (604)
N/A	4.4%(32)
Prehospital EMS intervention
Mechanical Cardiopulmonary Resuscitation	87.2% (624)
OHCA	Population 715, % (n)
Advanced airway a supraglottic airway device (iGel)	93% (670)
Intravenous Epinephrine	44% (315)
Prehospital Outcomes
Prehospital ROSC	9.2% (66)

OHCA: Out of hospital cardiac arrest, IQR: Interquartile range, UAEs: United Arab Emirates, EMS: Emergency medical service, CPR: Cardiopulmonary resuscitation, AED: Automated external defibrillator, ROSC: Return of spontaneous circulation, N/A: Not available, VF: Ventricular fibrillation, VT: Ventricular tachycardia, PEA: Pulses electrical activity.

Most of the cardiac arrest cases occurred to the patients in their homes/residences, that is 67.5% followed by streets and public places 22.5% and workplace 6.7%. Patients who had cardiac arrest in health-care centers were 2.7% and 0.4% in the Ambulance while being transported to hospitals [Figure 2]. The median response time from call received to Ambulance dispatch was 1.8 min and from Ambulance dispatch to scene arrival was 11.2 min.

Figure 2

Location of out of hospital cardiac arrest cases attended by the National Ambulance between June 2017 and July 2019

Almost half of the OHCA cases had witnessed arrest 51.7%, including 31.4% by the families, 16% by bystander laypersons and 4% by bystander health-care providers [Figure 3]. From the witnessed cardiac arrest, 197 patients received bystander cardiopulmonary resuscitation (CPR) as bystanders were guided by National Ambulance call talkers once cardiac arrest were suspected or confirmed. Automated external defibrillator (AED) was applied on 1.8% (n = 13) patients prior to arrival of National Ambulance.

Figure 3

The classification of witnessed out of hospital cardiac arrest patients between June 2017 and July 2018

A 95% of the total patients included in this study were transported to the closest hospitals (n = 682) and 5% were pronounced dead on the spot by physicians. Mechanical CPR (LUCAS-2, Physio control Inc., USA) was used by National Ambulance qualified EMTs and was applied on 87.2% (n = 624). CPR quality was not recorded in the study. In terms of using advanced airway, a supraglottic airway device iGel (Intersurgical Ltd., UK) was used for 93.7% (n = 670). Intravenous epinephrine was administered for 44% (n = 315).

The majority of the patients had nonshockable rhythms (83.2%). 12.5% had shockbale rhythms on the first rhythm analysis [Figure 4]. Prehospital defibrillation was performed by the National Ambulance crew and intravenous epinaphrine administered in 44% of the patients.

Figure 4

Presenting rhythms of out of hospital cardiac arrest patients between June 2017 and July 2018

From the total cases treated and transported by National Ambulance, 9.2% (n = 66) had return of spontaneous circulation (ROSC) at some stages. Majority of the ROSC patients were males that is 80% (n = 53). From the ROSC group, 42% (n = 28) received bystander CPR provided by family members of the patient 21% (n = 14), health-care provider 12% (n = 8) and laypersons 9% (n = 6). Automatic external defibrillator (AED) was applied by the bystanders on 2 of the ROSC patients before the arrival of National Ambulance. Asians had the highest percentage of ROSC group 62% (n = 41) followed by Arabs non-Emiratis 21.2% (n = 14) and local Emiratis 13.6% (n = 9). Of the 66 ROSC cases, 48% (n = 32) occurred in Sharjah, 22.7% (n = 15) in Ajman, 13% (n = 9) in Ras al-Khaimah, 12% (n = 8) in Fujairah and 3% (n = 2) in Abu Dhabi.

From the ROSC group, 85% (n = 56) received mechanical CPR (LUCAS-2, Physio control Inc., USA) and intravenous epinephrine. Advanced airway iGel (Intersurgical Ltd., UK) was inserted on 95% (n = 63). Prehospital defibrillation was attempted for 39.3% (n = 26) from the total ROSC group by the National Ambulance crew. Patients treated by National Ambulance crew were conveyed to 17 different emergency departments across the Emirates. In receiving hospitals; however, data on cardiac arrest patients and those discharged alive were not available.

DISCUSSION

The findings of this study showed an increase in the number of OHCA patients in Northern UAE about 39% as compared to the data published in 2016.[3] It can be explained in terms of population increase in the UAE. Majority of the patients consists of expats who were found to have higher percentages of cardiac arrest cases than UAE citizens.

In the study, more than half of the cardiac arrest cases, that is 51.7% (n = 370) were witnessed. On comparing the findings with data published in PAROS by Dubai Corporation for Ambulance Services, a similar percentage was found that is almost half of those cases 50.6% (n = 205) were also witnessed which is fairly close to the findings of this study.[4]

A gap in chain of survival was also identified. Even though witnessed cardiac arrest in this study was more than half of the cases, not all of them received bystander CPR, and it was given to merely half of them that is 53.2% (n = 197). The same issue was found in Dubai, where only 10.5% (n = 41) of the witnessed cardiac arrest patients received CPR through bystanders.[4]

Previous studies have hypothesized the reasons as to why general bystanders and families (non-healthcare providers) do not perform CPR for the patients. It was seen that due to lack of knowledge in recognizing a cardiac arrest and lack of confidence to perform CPR were the main reasons.[5] Furthermore, in this study, 23% (n = 167) OHCA patients were females showing low rate of bystander CPR performed to them that is only for 17% (n = 31) which can be attributed to cultural barriers. It was noticed from NA crew through anecdotal reports that most men did not want to or hesitated to touch females in public places, especially if the person was not a relative to the patient.

Furthermore, in UAE, “Good Samaritan Law” is not implemented and is not officially enacted; therefore, most of the people feel afraid of legal actions that can be taken against them if something wrong happened to the patient due to their first aid or interference. It is important to establish “Good Samaritan Law” in the United Arab Emirates to enhance community engagement and ensure proper implementation of chain of survival.

In the study findings, low public access to AED was found that is only 1.8% (n = 13) of the total OHCA patients had AED prior to the arrival of National Ambulance. It highlights the importance of conducting further researches to identify reasons behind low public access to AED.

The study results showed that the highest percentage of OHCA patients was expats and majority of them were Asians. Although important factors or reasons behind this incidence is unknown, it is noteworthy that about 66.35% of expats in UAE are Asians.[6] On the other hand, in 2018, a study from the American Heart Association in the United States stated that South Asian population is prone to develop heart diseases in the United States more than other groups.[7] The current research cannot identify exact causes and factors of high prevalence of cardiac arrest in the Asian population, and it is strongly suggested to conduct further studies and researches for the same.

Significant improvement in ROSC was found that is 9.2% and a majority of male patients that is 80%. It can be attributed to the enhancement of prehospital cardiac arrest care provided by National Ambulance. As the service in Northern UAE is mainly EMT-Basic, National Ambulance is trained and entitled in the scope of practice enabling EMT-Basics to administer intravenous fluid and epinephrine to the cardiac arrest patients, and further studies are required to be conducted about the effectiveness of adrenaline in OHCA.[8910]

From the ROSC group, 42% (n = 28) received bystander CPR performed and 2 had AED applied on them by the public before the National Ambulance crew arrived. The study findings reflect that there has been an improvement in community engagement. At the National Ambulance Call Center (ACC) once a cardiac arrest is confirmed or suspected by the caller, the call takers provide CPR instructions to the person. The call takers can communicate in eight spoken languages to guide callers correctly; however, not all callers perform a CPR which could be due to lake of knowledge and confidence in performing it appropriately. It has previously been clarified in other studies that expanding the community awareness about sudden cardiac arrests is of crucial importance.[11] It is very important for families of patients who may suffer chronic illnesses, to be trained on how to perform CPR[12]

The findings of the study show that higher prevalence is in elderly patients than youth, and the majority of them have chronic diseases such as heart disease, hypertension, diabetes, and respiratory diseases. It was also found that 69.9% of cases occurred to the victims in their homes/residences.[1]

Data were collected for this study evaluates the prehospital setting only, and unfortunately, at the hospitals, discharge data of such patients were not available. It cannot be confirmed if number of patients availing National Ambulance service is the total number of OHCA patients, as there could be patients who are transported to hospitals by private conveyance or are declared dead on the spot.

CONCLUSION

The study shows that it is very important to enhance the level of public awareness of OHCA and develop customized training programs for the community on how to perform bystander CPR. Low public access to AED was found in this study; therefore, it is important to investigate the reasons behind this in further studies.

The first three elements of chain of survival for OHCA are provided by the community, and to enhance the engagement of the community, it is required to implement Good Samaritan Law in UAE, to help the community identify their rights and limitations. It is also of great importance to build strong data linkages between ambulance services and hospitals to be sure that all OHCA in the country is reported, recorded, and measured. All the ROSC patients in this study were captured in prehospital setting, and their status on survival or death was not available. Therefore, the decision on data continuity is urgently required to be taken.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.