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Actions Taken by Bystanders During Sudden Cardiac Arrest: Analysis of Emergency Medical Service Documentation in
Rafał Milewski1, Jolanta Lewko2, Gabriela Milewska3
1Department of Integrated Medical Care, Medical University of Bialystok, 15-096 Bialystok, Poland.
Insights
Bystander cardiopulmonary resuscitation (CPR) significantly increases survival rates for out-of-hospital cardiac arrest (OHCA) patients. Early defibrillation and alternative airway management also improve the chances of return of spontaneous circulation (ROSC).
Area of Science:
- Emergency Medicine
- Cardiology
- Public Health
Background:
- Sudden cardiac arrest (SCA) is a critical event requiring immediate intervention.
- The chain of survival emphasizes early recognition, CPR, defibrillation, and post-resuscitation care.
- Bystander actions are crucial in improving outcomes for out-of-hospital cardiac arrest (OHCA).
Purpose of the Study:
- To analyze OHCA cases and evaluate the impact of bystander interventions.
- To assess the effectiveness of cardiopulmonary resuscitation (CPR) initiated by bystanders.
- To determine factors influencing return of spontaneous circulation (ROSC) in OHCA patients.
Main Methods:
- Analysis of 49,649 dispatch records from an emergency medical team (EMT) in Bialystok (2018-2019).
- Comparison of ROSC rates based on whether bystanders performed CPR.
- Evaluation of ROSC rates related to specific cardiac arrest rhythms (VF/pVT, Asystole/PEA) and airway management techniques.
Main Results:
- ROSC occurred in 30.53% of cases with bystander CPR versus 2.35% without.
- ROSC rates were 58.62% for ventricular fibrillation (VF)/pulseless ventricular tachycardia (pVT) rhythms and 26.56% for asystole/pulseless electrical activity (PEA).
- Alternative airway management showed higher ROSC (83.33%) compared to intubation (58.73%) in VF/pVT OHCA cases.
Conclusions:
- Bystander CPR initiation is the most critical factor for achieving ROSC in OHCA.
- Defibrillation-indicated rhythms (VF/pVT) significantly increase the likelihood of ROSC.
- Alternative airway management techniques may offer superior outcomes in specific OHCA rhythms.
Abstract:
Background/Objectives: Sudden cardiac arrest (SCA) is a severe medical condition involving the cessation of the heart's mechanical activity. Following the chain of survival, which includes early recognition and calling for help, early initiation of cardiopulmonary resuscitation (CPR), early defibrillation, and post-resuscitation care, offers the greatest chances of saving a person who has experienced SCA. The aim of this study was to analyze cases of out-of-hospital cardiac arrest (OHCA) and assess the actions taken by bystanders. Methods: The input for analysis consisted of 49,649 dispatch records from the emergency medical team (EMT) at the Voivodeship Emergency Medical Station in Bialystok in 2018-2019. Results: Among the patients where bystanders performed CPR, the return of spontaneous circulation (ROSC) occurred in 30.53% of cases, whereas in the cases where the bystander did not perform CPR, ROSC occurred in 2.35% of cases. When cardiac arrest rhythm was ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT), ROSC occurred in 58.62% of cases, while there was asystole or pulseless electrical activity (PEA) present, ROSC occurred in 26.56% of cases. In patients who experienced OHCA in a VF/pVT rhythm and who underwent intubation, ROSC occurred in 58.73% of cases, whereas in patients who underwent alternative procedures for airway management, ROSC occurred in 83.33% of cases. Conclusions: The most significant factor influencing the occurrence of ROSC in patients is CPR initiation by bystanders. The presence of a rhythm that requires defibrillation increases the likelihood of achieving ROSC in the patient. Alternative methods for airway management appear to be more beneficial in VF/pVT rhythms.
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