Video Streaming or Telephone Communication During Emergency Medical Services Dispatch Calls: A Cluster Randomized Clinical Trial.

Importance: Video streaming during emergency medical calls may enhance triage precision and optimize health resource allocation. However, its clinical safety and effect on key outcomes remain unexplored in randomized clinical trials. Objective: To assess whether video streaming during emergency calls reduces highest-urgency ambulance dispatches while ensuring safety through outcomes such as 24-hour hospital admissions among initially nonconveyed patients, mortality, and intensive care unit (ICU) admissions. Design, Setting, and Participants: This cluster randomized clinical trial was conducted across 4 months (January 1 through April 30, 2023) at a single emergency medical dispatch center serving 1.3 million residents in the Central Denmark Region. Matched pairs of dispatchers were randomized to manage calls using either telephone only communication (control) or video streaming (intervention). Calls were routed to the next available dispatcher who had been idle the longest. Data were analyzed using the intention-to-treat approach. Intervention: Dispatchers in the intervention group used secure, 1-way smartphone video streaming during emergency calls, while the control group followed standard telephone protocols. Main Outcomes and Measures: The primary outcome was the percentage of ambulances dispatched at the highest urgency level. Secondary outcomes included 24-hour hospital admissions among initially nonconveyed patients, ICU admission, mortality rates, and dispatch call duration. Results: Of 18 745 calls (patient median [IQR] age, 57 [31-76] years; 54.4% female), 8124 were received by 10 dispatchers randomized to video streaming and 10 621 by 10 dispatchers randomized to telephone-only communication. Video streaming was established in 3706 of the 8124 calls (45.6% [95% CI, 44.6%-46.7%]). Compared with the control group, the intervention group demonstrated a 5.0% absolute reduction (95% CI, 0.0%-10.1%; P = .049) in highest-urgency ambulance dispatches and no significant change (4.5% increase [95% CI, -1.1% to 10.0%; P = .11]) in nonconveyance. Hospital admissions among initially nonconveyed patients within 24 hours were reduced by 2.0% (95% CI, -3.7% to -0.2%; P = .03). Mean dispatch time was 3.7 minutes (95% CI, 3.4-4.0 minutes) in the video streaming group vs 3.2 minutes (95% CI, 2.9-3.4 minutes) in the telephone-only group, a difference of 0.5 minutes (95% CI, 0.1-0.9 minutes; P = .02). Mortality rates at 30 days and ICU admission rates were not statistically different between the 2 groups. Conclusions and Relevance: In this cluster randomized clinical trial assessing high-stakes emergency calls, video streaming reduced the frequency of highest-urgency ambulance dispatches and lowered hospital admissions among initially nonconveyed patients, but slightly increased dispatch times. These findings suggest that video streaming may improve triage accuracy and reduce hospital and prehospital resource use. Trial Registration: ClinicalTrials.gov Identifier: NCT05742412.