Temporal trends in the incidence and outcomes of shock-refractory ventricular fibrillation out-of-hospital cardiac...

Area of Science:

• Emergency Medicine
• Cardiology
• Public Health

Background:

• Out-of-hospital cardiac arrest (OHCA) presents significant survival challenges.
• Refractory ventricular fibrillation (RVF) is a critical subtype of OHCA requiring intensive resuscitation.
• Understanding trends in RVF incidence and outcomes is crucial for improving patient survival.

Purpose of the Study:

• To analyze trends in the incidence and outcomes of RVF versus non-RVF in OHCA patients.
• To identify factors associated with RVF development and survival.
• To evaluate the impact of early interventions on RVF outcomes.

Main Methods:

• Retrospective analysis of OHCA cases in Victoria, Australia (2010-2019).
• Inclusion criteria: adults (≥16 years) with initial shockable rhythm and attempted resuscitation.
• Statistical analysis included logistic regression to assess RVF incidence, survival, and associated factors.

Main Results:

• RVF incidence declined from 7.7 to 5.6 per 100,000 population (p-trend=0.01).
• Survival to hospital discharge improved for both RVF (26% to 31%) and non-RVF (41% to 53%) groups.
• RVF was associated with reduced survival (OR=0.503); witnessed arrest, bystander CPR, and defibrillation improved outcomes.

Conclusions:

• The incidence of RVF in OHCA is decreasing, with concurrent improvements in survival rates.
• Early bystander cardiopulmonary resuscitation (CPR) and defibrillation are key factors in reducing RVF incidence.
• Continued focus on public access defibrillation and CPR training is vital for improving OHCA survival.