Long-term trends in the epidemiology of out-of-hospital cardiac arrest precipitated by suspected drug overdose

Cardiac Arrest Following Drug Overdose in the United States: An Analysis of the Cardiac Arrest Registry to Enhance Survival

BACKGROUND

Given increases in drug overdose-associated mortality, there is interest in better understanding of drug overdose out-of-hospital cardiac arrest (OHCA). A comparison between overdose-attributable OHCA and nonoverdose-attributable OHCA will inform public health measures.

METHODS AND RESULTS

We analyzed data from 2017 to 2021 in the Cardiac Arrest Registry to Enhance Survival (CARES), comparing overdose-attributable OHCA (OD-OHCA) with OHCA from other nontraumatic causes (non-OD-OHCA). Arrests involving patients <18 years, health care facility residents, patients with cancer diagnoses, and patients with select missing data were excluded. Our main outcome of interest was survival with good neurological outcome, defined as Cerebral Performance Category score 1 or 2. From a data set with 537 100 entries, 29 500 OD-OHCA cases and 338 073 non-OD-OHCA cases met inclusion criteria. OD-OHCA cases involved younger patients with fewer comorbidities, were less likely to be witnessed, and less likely to present with a shockable rhythm. Unadjusted survival to hospital discharge with Cerebral Performance Category score =1 or 2 was significantly higher in the OD-OHCA cohort (OD: 15.2% versus non-OD: 6.9%). Adjusted results showed comparable survival with Cerebral Performance Category score =1 or 2 when the first monitored arrest rhythm was shockable (OD: 28.9% versus non-OD: 23.5%, P=0.087) but significantly higher survival rates with Cerebral Performance Category score =1 or 2 for OD-OHCA when the first monitored arrest rhythm was nonshockable (OD: 9.6% versus non-OD: 3.1%, P<0.001).

CONCLUSIONS

Among patients presenting with nonshockable rhythms, OD-OHCA is associated with significantly better outcomes. Further research should explore cardiac arrest causes, and public health efforts should attempt to reduce the burden from drug overdoses.

Initial Outcomes and Survival of Out-of-Hospital Cardiac Arrest: EuReCa Serbia Multicenter Cohort Study

Introduction Although the global survival rate of patients after out-of-hospital cardiac arrest (OHCA) has increased in the previous years, there still remain significant multifactorial public health challenges with many important aspects influencing the overall survival rate of these patients. The objective of this article is to analyze basic epidemiological parameters of OHCA in Serbia and to evaluate the influence of pre-hospitalization factors on the survival of OHCA patients. Methods Data on OHCA within the EuReCa Serbia Registry was collected according to the EuReCa Study protocol during the period October 1, 2014 - December 31, 2019, and included basic demographic data of the patients, data related to OHCA prior to hospital arrival, as well as data regarding subsequent hospitalization. Results The study included 6,266 EuReCa events (54% males), with a median age of 73 years [interquartile range (IQR) 63-82]. Cardiac arrest was witnessed in 3,111 out of 6,266 cases (49.6%), of which 2,725 cases (87.6%) were witnessed by bystanders and 286 cases (12.4%) by the emergency medical service (EMS) team. Resuscitation measures were attempted in 2,097 of 3,111 (67.4%) witnessed OHCA cases. Bystander cardiopulmonary resuscitation (CPR) was initiated in 288 cases within the bystander-witnessed group of 2,725 cases (10.6%). An initial shockable rhythm was detected in 323 out of 3,111 witnessed cases (10.4%). Any return of spontaneous circulation (ROSC) prior to hospital arrival was observed in 441 out of 2,097 cases where CPR was initiated (21.0%). Within the group of 2,097 events where CPR was initiated, in 287 cases the patient was transported to the hospital with ROSC (13.7%). An automated external defibrillator (AED) was used by bystanders in three cases. The collapse in locations other than the place of residence [p < 0.01; odds ratio (OR) 3.928], attempt to initiate CPR by a bystander (p < 0.01; OR 2.169), and presence of initial shockable rhythm (p = 0.01; OR 2.070) were observed as significant predictors of any ROSC in OHCA patients. Out of 287 patients hospitalized with ROSC, 54 (18.8%) were discharged alive. Conclusion Collapse outside of residence place, bystander CPR initiation, and initially detected shockable rhythm are important predictors of ROSC prior to hospital arrival and overall survival. Key factors of CPR-providing performance observed in this study were witnessing OHCA, CPR initiated by a bystander, presence of initial shockable rhythm, and any ROSC prior to hospital arrival.