AUTOMATIC EMS ALERT WITH REAL-TIME PATIENT LOCATION AFTER WCD SHOCK DELIVERY: IMPROVING THE CHAIN OF SURVIVAL

Abstract

BackgroundVentricular fibrillation (VF) commonly occurs at home and is unwitnessed. Wearable cardioverter defibrillators (WCD) are effective in terminating VF, but patients may need assistance afterwards.ObjectiveTo evaluate feasibility of a novel shock alert system linking a WCD (ASSURE® WCD system, Kestra Medical Technologies) to Emergency Medical Services (EMS).MethodsWCD shock delivery triggers creation of a shock event message via patient app including location derived from GPS, cellular and WiFi networks. The message is transferred to an emergency response data platform (ERDP) which determines physical address and associated local EMS, and displays this information to a public safety call center via web portal (Figure 1).Simulations of message transfer were performed to evaluate compliance with applicable standards for time to alarm (UL 1635 Digital Alarm Communicator System Units) and reliability of triggering devices (UL 1637 Home Health Care Signaling Equipment). A waveform generator was used to input VF into the WCD. An automated test system recorded total shocks and shock event messages received by the ERDP. Throughput was compared to the standard for rate (max missed messages 38/100,000) and time (max delay <90s).Simulated complete shock alert process duration was measured over repeated tests using a waveform generator and WCD at a remote test location.ResultsWCD delivered 8,680 shocks and transferred 8,680 (100%) shock event messages to the ERDP. Mean time to transfer was 5.2 ± 3.4 s exceeding compliance standard throughput requirements with 95% confidence.For the simulated complete shock alert process, mean time from VF onset to dispatch operator call was 57 ± 3 s in three tests.Conclusions BackgroundVentricular fibrillation (VF) commonly occurs at home and is unwitnessed. Wearable cardioverter defibrillators (WCD) are effective in terminating VF, but patients may need assistance afterwards. Ventricular fibrillation (VF) commonly occurs at home and is unwitnessed. Wearable cardioverter defibrillators (WCD) are effective in terminating VF, but patients may need assistance afterwards. ObjectiveTo evaluate feasibility of a novel shock alert system linking a WCD (ASSURE® WCD system, Kestra Medical Technologies) to Emergency Medical Services (EMS). To evaluate feasibility of a novel shock alert system linking a WCD (ASSURE® WCD system, Kestra Medical Technologies) to Emergency Medical Services (EMS). MethodsWCD shock delivery triggers creation of a shock event message via patient app including location derived from GPS, cellular and WiFi networks. The message is transferred to an emergency response data platform (ERDP) which determines physical address and associated local EMS, and displays this information to a public safety call center via web portal (Figure 1).Simulations of message transfer were performed to evaluate compliance with applicable standards for time to alarm (UL 1635 Digital Alarm Communicator System Units) and reliability of triggering devices (UL 1637 Home Health Care Signaling Equipment). A waveform generator was used to input VF into the WCD. An automated test system recorded total shocks and shock event messages received by the ERDP. Throughput was compared to the standard for rate (max missed messages 38/100,000) and time (max delay <90s).Simulated complete shock alert process duration was measured over repeated tests using a waveform generator and WCD at a remote test location. WCD shock delivery triggers creation of a shock event message via patient app including location derived from GPS, cellular and WiFi networks. The message is transferred to an emergency response data platform (ERDP) which determines physical address and associated local EMS, and displays this information to a public safety call center via web portal (Figure 1). Simulations of message transfer were performed to evaluate compliance with applicable standards for time to alarm (UL 1635 Digital Alarm Communicator System Units) and reliability of triggering devices (UL 1637 Home Health Care Signaling Equipment). A waveform generator was used to input VF into the WCD. An automated test system recorded total shocks and shock event messages received by the ERDP. Throughput was compared to the standard for rate (max missed messages 38/100,000) and time (max delay <90s). Simulated complete shock alert process duration was measured over repeated tests using a waveform generator and WCD at a remote test location. ResultsWCD delivered 8,680 shocks and transferred 8,680 (100%) shock event messages to the ERDP. Mean time to transfer was 5.2 ± 3.4 s exceeding compliance standard throughput requirements with 95% confidence.For the simulated complete shock alert process, mean time from VF onset to dispatch operator call was 57 ± 3 s in three tests. WCD delivered 8,680 shocks and transferred 8,680 (100%) shock event messages to the ERDP. Mean time to transfer was 5.2 ± 3.4 s exceeding compliance standard throughput requirements with 95% confidence. For the simulated complete shock alert process, mean time from VF onset to dispatch operator call was 57 ± 3 s in three tests. Conclusions