Operational Characteristics and System Readiness of Advanced Water-Based EMS Units Along the Chao Phraya River in Bangkok: A Retrospective Descriptive Study.

INTRODUCTION: Water-related emergencies are a major urban public health concern, particularly along Bangkok's heavily trafficked Chao Phraya River. Between 2019 and 2023, Bangkok reported the third-highest drowning mortality rate in Thailand. Although advanced water-based emergency medical service (EMS) units have operated for more than three decades, their operational characteristics have not been systematically evaluated. OBJECTIVE: To describe the operational characteristics and system structure of advanced water-based EMS units operating along the Chao Phraya River in Bangkok. METHODS: A retrospective descriptive study analyzed operational data from January 1, 2021, to December 31, 2023, using mission report databases from the Bangkok Metropolitan Administration EMS Center and three designated advanced water-based EMS units. Key variables included annual incident notifications, mission characteristics, operational outcomes, and system structure. RESULTS: Descriptive evaluation identified several system limitations across all units, including inadequate docking infrastructure, shortages of specialized medical equipment, and the absence of standardized clinical protocols and performance monitoring. Comprehensive quantitative analysis was not possible for Units 2 and 3 because of incomplete operational records. Unit 1 recorded 28, 71, and 52 incident notifications in 2021, 2022, and 2023, respectively, resulting in 11, 50, and 18 EMS missions. Medical assistance was provided in 1, 11, and 9 cases, respectively. These findings are presented descriptively and should not be interpreted as comparisons between units because comparable operational data were unavailable for Units 2 and 3. CONCLUSION: Available data indicate important gaps in infrastructure, documentation, standardized reporting, and performance monitoring within Bangkok's water-based EMS system. Strengthening the system will require improved docking infrastructure, standardized medical equipment, digitized reporting systems, and the implementation of continuous quality improvement processes.