Effectiveness of Video-assisted Cardiopulmonary Resuscitation Under Special Circumstances: a Randomized Controlled Simulation Study

Out-of-hospital cardiac arrest (OHCA) remains a major global health concern and one of the leading causes of mortality in industrialized nations. Despite various public health initiatives aimed at increasing layperson engagement in early intervention, bystander cardiopulmonary resuscitation (CPR) rates continue to vary widely across countries, ranging from 13% to 82%. Survival after OHCA is strongly associated with the early recognition of cardiac arrest, rapid activation of emergency medical services (EMS), and immediate initiation of effective CPR. In most cases, the first responder is a layperson who contacts the emergency dispatcher-making dispatcher-assisted CPR a critical link in the chain of survival.

Telephone-assisted CPR (T-CPR), where the dispatcher provides audio instructions, is a widely adopted and effective method to initiate life-saving efforts. However, the lack of visual feedback limits its potential: the dispatcher cannot observe the victim's condition, the responder's technique, or the scene dynamics. As a result, certain errors may go uncorrected, and the quality of CPR may be suboptimal.

With advancements in communication technology, real-time video communication between dispatchers and callers has become feasible. Video-assisted CPR (V-CPR) allows dispatchers to visually assess the situation, provide tailored feedback, and correct lay responder errors during the intervention. Several simulation studies have demonstrated that V-CPR can improve CPR performance compared to T-CPR, particularly in terms of compression rate, hand placement, and technique. However, the evidence regarding its superiority in achieving guideline-recommended compression depth remains mixed. Furthermore, the added complexity of initiating a video call and ensuring optimal camera positioning can delay CPR initiation and affect its effectiveness.

While prior studies have explored the technical feasibility and clinical benefits of V-CPR, the influence of environmental and situational variables-such as background noise, poor lighting conditions, or the presence of distractions-remains underexplored. These factors are highly relevant in real-world emergencies and may impact both the lay responder's performance and the dispatcher's ability to guide the process effectively.

Our study aimed to address this gap by conducting a simulation trial to compare the effectiveness of T-CPR and V-CPR under both ideal and environmentally challenging conditions. By systematically examining the impact of common distracting factors, our goal was to better understand the limitations and potential of video-assisted emergency guidance in realistic layperson resuscitation scenarios.