Association between hourly call volume in the emergency medical dispatch center and dispatcher-assisted cardiopulmonary resuscitation instruction time in out-of-hospital cardiac arrest

The barriers and facilitators to initiation of telephone-assisted bystander cardiopulmonary resuscitation for patients experiencing out-of-hospital cardiac arrest in a private emergency dispatch centre in South Africa

Background

The incidence of cardiovascular diseases, and with it out-of-hospital cardiac arrest (OHCA), is on the increase in low- to middle-income countries (LMICs), like South Africa. Interventions such as mass public cardiopulmonary resuscitation (CPR) training campaigns and public access defibrillators are expensive and out of reach for many LMICs. Telephone-assisted CPR (tCPR) is a cost-effective, scalable alternative. This study explored the barriers and facilitators to tCPR uptake in OHCA in a private South African emergency dispatch centre.

Methods

This qualitative study applied inductive dominant content analysis to emergency call recordings of OHCA cases into a private emergency dispatch centre. Calls were analysed to the latent level to identify barriers and facilitators. Cases were sampled randomly, until data saturation.

Results

Saturation occurred after the analysis of 25 recordings. A further three recordings were analysed to confirm saturation of the facilitators; yielding a final sample size of 28 calls. Overall, t-CPR was offered in 23 (82.1%) cases, but only initiated in 8 (34.8%) of these calls. Five barriers ("Poor Communication"; "Lack of Support"; "Caller Hesitance or Uncertainty;" "Emotionality"; and "Practical Barriers") and three facilitators ("Caller Willingness"; "Support" and "CPR in Progress") were extracted.

Conclusion

Numerous barriers limit the initiation of tCPR in the South African private sector EMS. It is crucial to address these barriers and leverage the facilitators in order to improve tCPR uptake. This study highlights the importance of using specific language techniques and developing tailored tCPR algorithms to overcome these barriers, which is underpinned by standardised training of call-takers.

Impact of crowding in local ambulance demand on call-to-ambulance scene arrival in out-of-hospital cardiac arrest

BACKGROUND

Rapid emergency medical service (EMS) response is an important prognostic factor in out-of-hospital cardiac arrest (OHCA). This study aims to evaluate the association between local hourly EMS demand and ambulance response in OHCA.

METHODS

OHCA occurring in 24 districts of Seoul from 2013 to 2018 was analyzed. Hourly ambulance demand per ambulance in each local district of patient location at the hour of cardiac arrest was calculated as the crowding index. The crowding index was categorized according to quartiles (1Q: ≤0.43, 2Q: 0.44-0.67, 3Q: 0.68-0.99, 4Q: ≥1.0 calls/h\r/ambulance). The primary outcome was ambulance dispatched within 1 km of the OHCA scene. Multivariable logistic regression analysis was performed to test the association between the local hourly ambulance demand and outcomes.

RESULTS

A total of 26,479 patients were analyzed. The rate of ambulance dispatched within 1 km decreased according to the crowding quartile (1Q: 31.3%, 2Q: 30.0%, 3Q: 28.8%, and 4Q: 26.6%). Compared to 1Q, adjusted odds ratios (95% CIs) of dispatch distance within 1 km in 2Q, 3Q, and 4Q were 0.92 (0.86-0.99), 0.86 (0.80-0.94), and 0.77 (0.71-0.84), respectively.

CONCLUSION

Crowding in local ambulance demand was associated with less ambulance dispatched within 1 km and delayed response to the scene in OHCA. Strategies to mitigate and adjust to ambulance demand crowding may be considered for better EMS response performance.

Comparison between dispatcher-assisted bystander CPR and self-led bystander CPR in out-of-hospital cardiac arrest (OHCA)

INTRODUCTION

Bystander cardiopulmonary resuscitation (CPR) is an important prognostic factor for outcome in out-of-hospital cardiac arrest (OHCA). The dispatcher-assisted (DA) bystander CPR program has increased the rate of bystander CPR by targeting bystanders with a lower level of CPR training. We evaluated the effects of dispatcher-assisted bystander CPR and self-led bystander CPR.

METHODS

A retrospective analysis was performed using a nationwide OHCA database from 2014 to 2018. Adult EMS-treated OHCA patients with presumed cardiac origin were enrolled. OHCAs were classified into 3 groups according to the type of bystander CPR (DA bystander CPR vs. self-led bystander CPR vs. no bystander CPR) provided. The primary outcome was good neurologic recovery at hospital discharge. A multivariable logistic regression model was used to estimate the association between the type of bystander CPR and outcomes.

RESULTS

A total of 91,557 eligible OHCA patients was enrolled in the final analysis. The proportion of patients with favorable neurologic outcomes was highest with self-led bystander CPR (9.0% for self-led bystander CPR, 5.2% for DA bystander CPR and 3.2% for no bystander CPR, p < 0.01). Self-led bystander CPR was associated with better neurological recovery than DA bystander CPR (aOR with 95% CI (DA-CPR as reference): 0.63 (0.58-0.69) for no bystander CPR, 1.28 (1.17-1.40) for self-led bystander CPR).

CONCLUSION

Although DA CPR was associated with better neurologic outcomes than no bystander CPR, good neurologic outcomes were most strongly associated with self-led bystander CPR.