Pre-hospital Timings and Life-saving Interventions in Trauma Related Mass Casualty Incidents: Investigating Delays, Interventions, and Barriers to Care

Abstract

Introduction: Mass casualty incidents (MCIs) are rising globally, resulting in nearly two million fatalities and countless injuries over the past two decades. Delays in pre-hospital time (PHT) during MCIs contribute to preventable deaths, particularly among those requiring life-saving interventions. Decisions regarding these essential interventions often rely on assumptions, which can potentially undermine the effectiveness of triage and worsen patient outcomes. The overall objective of this thesis was to examine PHT in trauma-related MCIs, including its associated delays, and measure the average timings for performing MCI life-saving interventions.

Methods: A systematic review was conducted to identify trauma-related MCI reports that described PHTs and the factors associated with delays. This was followed by a simulation study at two training centres, where physicians and paramedics performed 16 predefined life-saving interventions in a controlled pre-hospital environment. These interventions were selected based on a previously conducted narrative literature review, and the duration of each was recorded and analysed. Finally, an international cross-sectional survey was disseminated through professional networks to pre-hospital care providers to explore perceived barriers contributing to PHT delays during trauma-related MCIs.

Results: The systematic review identified 14 eligible studies, with pre-hospital times ranging from 35 minutes to over 8 hours. Delays were most often linked to scene safety concerns, complex environments, and triage decisions rather than casualty numbers. In the simulation study, 20 pre-hospital care providers completed nearly all life-saving interventions in under 130 seconds, except for rapid sequence intubation, which required a median of 348 seconds (IQR: 329–366 seconds). Preparation and post-placement steps caused the most significant delays in advanced interventions. Participants tended to overestimate the time required to perform each intervention, with notable differences observed in supraglottic airway insertion, cricothyroidotomy, needle decompression, and finger thoracostomy (all p < 0.05). The international survey (n = 225, 54 countries) revealed that communication failures (84%) and geographic barriers (80%) were the leading contributors to prolonged PHT. Equipment shortages and hospital distance were more prominent in low-resource settings (75% and 63%, respectively). Qualitative results also indicated that resource limitations posed greater challenges in low- or middle-income countries, whereas respondents from high-income countries more frequently cited policy and administrative barriers. Most participants cited regular training (95%) and prior MCI experience (90%) as critical for improving PHT.

Conclusion: Collectively, delays during MCIs are multifactorial, involving geographical, logistical, procedural, and perceptual challenges. The simulation study demonstrated that most life-saving interventions can be delivered rapidly, supporting their inclusion in MCI triage protocols. Findings from this thesis highlight the need for enhanced communication systems, targeted training, and context-specific response planning to mitigate pre-hospital delays and improve outcomes for critically injured patients in mass casualty settings.