Out-of-hospital cardiac arrest (OHCA) occurs when the heart unexpectedly stops beating outside of a hospital or medical facility. This sudden cessation of the heart’s pumping function leads to an immediate loss of blood flow and oxygen to vital organs. OHCA is a life-threatening emergency demanding swift intervention, as time is critical for survival. Globally, the estimated survival rate for patients experiencing OHCA remains low, often less than 10%.
The Most Common Locations
Most out-of-hospital cardiac arrests occur in residential settings, with approximately 70% to 73.9% happening in homes. This means the life a bystander might save is often a family member or friend. Public settings account for about 15.1% to 16.3% of OHCAs. Nursing homes and long-term care facilities represent another significant location, accounting for around 10.3% to 10.9% of incidents.
Factors Influencing Occurrence
The prevalence of OHCA in residential settings is influenced by several factors. Individuals experiencing OHCA in homes are often older, with a median age of 65 years, and may have pre-existing conditions. Over 50% of these events are unwitnessed, meaning no one is present to immediately identify the cardiac arrest.
Even when witnessed by family members, bystander cardiopulmonary resuscitation (CPR) may be less likely to be initiated compared to events witnessed by non-family members. In contrast, OHCAs in public places are more frequently witnessed, leading to a higher likelihood of resuscitation attempts.
Nursing homes, despite having healthcare workers present who can initiate immediate CPR, still show low survival rates for OHCA. This may be due to the elderly population often having significant comorbidities, which can complicate outcomes.
The Impact of Immediate Action
The location of an OHCA significantly impacts the chances of survival, especially through immediate bystander intervention. If performed immediately, CPR can double or triple the chance of survival. For every minute without intervention, the probability of survival decreases by 7% to 10%.
Early recognition of cardiac arrest and prompt activation of emergency services are crucial first steps. Immediate CPR and Automated External Defibrillator (AED) use are vital, as early defibrillation can increase survival rates to 70% or more within minutes.
In residential settings, bystanders are often family or friends, making their readiness to act important. Bystander CPR has been associated with a 24% higher likelihood of surviving to hospital discharge in older adults.
Empowering Community Response
Equipping individuals and communities with the knowledge and skills to respond to OHCA can improve outcomes. Learning CPR is a practical step, with various organizations offering training courses. Many resources, including online platforms, can teach CPR in as little as 15 minutes.
Knowing the location of AEDs in public spaces and how to activate emergency medical services quickly are also important. Registering community AEDs with emergency services can help direct bystanders to the nearest device during an emergency. Community interventions, such as public CPR training and awareness campaigns, can increase bystander CPR rates and improve overall survival.