Out-of-hospital cardiac arrest (OHCA) is widely recognized as a global health issue. However, little is known about OHCA epidemiology in the former Union of Soviet Socialist Republics (USSR) territories.^[1,2] The 15 post-Soviet states occupy nearly one-sixth of the land surface of the earth, and the total population exceeds 292 million people. However, there are no sound well-organized systems for continuous epidemiological surveillance and monitoring of emergency medical services (EMS) performance in OHCA. An OHCA registry would have the potential benefit of identifying ways to improve OHCA survival rates.

The Crimean out-of-hospital cardiac arrest and resuscitation registry (COHCARR) was recently introduced as a prospective registry of all EMS-attended cases of OHCA with attempted cardiopulmonary resuscitation (CPR), covering the entire population of 1.914 million people living in Crimea (with the exception of the Sebastopol).^[3]

An analysis of baseline 24-month data (from January 2018 to December 2019) was conducted. During this period, the EMS of Crimea attended a total of 26,045 OHCA events (680.4 per 100,000 resident population per year). Resuscitation was commenced in 3.9% (n=1,018) of cases, and the incidence of OHCA resuscitation attempts was 26.6 per 100,000 population per year. In the majority of cases, the EMS providers did not initiate CPR, since there were obvious signs of irreversible death at time of the primary survey. Of the cases where CPR was initiated, the collapse was witnessed by EMS (n=737, 72.4%) and by bystanders (n=250, 24.6%). However, resuscitation was initiated by lay people only in 28.8% (72/250) of cases of the bystander-witnessed OHCA. With the exception of EMS-witnessed cases, the mean EMS response time was 13 minutes (4 minutes for all analyzed OHCA cases). About 11.9% (n=121) of patients had an initial shockable rhythm. The rate of return of spontaneous circulation (ROSC) was 5.9% (n=60), and 5.1% (n=52) survived until arrival at the hospital. There were 35 patients in the Utstein comparator group (bystander-witnessed OHCA with initial shockable rhythm). Three patients gained ROSC and survived to the hospital arrival.

The low rate of EMS-attempted resuscitation in Crimea has been attributed to the predominant inability of bystanders to rapidly recognize cardiac arrest, activate the EMS, and start basic life support. The rarity of ROSC and survival in OHCA with attempted CPR may be attributable to the late initiation and suboptimal performance of resuscitation. The low percentage of cases with an initial shockable rhythm suggests delayed care.

A recent survey of adult inhabitants of Crimea showed that about 50% of citizens were previously trained in resuscitation, but most of them passed their training more than a year prior to the survey and nearly half were trained only once.^[4] The respondents demonstrated poor knowledge of resuscitation and reported the lack of knowledge as the strongest barrier to attempt CPR.^[4]

In Crimea, OHCA constitutes a serious problem for public health. Urgent interventions to increase the effectiveness of prehospital care and improve survival from OHCA are needed. Public resuscitation training and dispatcher-assisted CPR programs could be the foreground measures to increase the rates of bystander CPR and improve outcomes of OHCA on the Crimean peninsula. Being an indispensable tool for measuring the impact of interventions and driving further enhancement of prehospital care in Crimea, the COHCARR may be recommended as a basic model to establish cardiac arrest registries in other former Soviet Union territories, with the goal of improving outcomes of OHCA.

Funding: None.

Ethical approval: Not needed.

Conflicts of interest: The author has no competing interests relevant to the present study.

Contributors: AB conceived, designed, wrote, and approved the final version of the manuscript.