Factors Associated with the Number of Injured and Fatalities in Motor Vehicle Intentional Mass-Casualty Incidents: A Timely Aid for Scaling the Emergency Response

INTRODUCTION

Intentional mass-casualty incidents (IMCIs) involving motor vehicles (MVs) as weapons represent a growing trend in Western countries. This method has resulted in the highest casualty rates per incident within the field of IMCIs. Consequently, there is an urgent requirement for a timely and accurate casualty estimation in MV-induced IMCIs to scale and adjust the necessary health care resources.

STUDY OBJECTIVE

The objective of this study is to identify the factors associated with the number of casualties during the initial phase of MV-IMCIs.

METHODS

This is a retrospective, observational, analytical study on MV-IMCIs world-wide, from 2000-2021. Data were obtained from three different sources: Targeted Automobile Ramming Mass-Casualty Attacks (TARMAC) Attack Database, Global Terrorism Database (GTD), and the vehicle-ramming attack page from the Wikipedia website. Jacobs' formula was used to estimate the population density in the vehicle's route. The primary outcome variables were the total number of casualties (injured and fatalities). Associations between variables were analyzed using Spearman's correlation coefficient and simple linear regression.

RESULTS

Forty-six MV-IMCIs resulted in 1,636 casualties (1,430 injured and 206 fatalities), most of them caused by cars. The most frequent driving pattern was accelerating whilst approaching the target, with an average speed range between four to 130km/h and a distance traveled between ten to 2,260 meters. The people estimated in the MV-IMCI scenes ranged from 36-245,717. A significant positive association was found of the number affected with the estimated crowd in the scene (R2: 0.64; 95% CI, 0.61-0.67; P <.001) and the average vehicle speed (R2: 0.42; 95% CI, 0.40-0.44; P = .004).

CONCLUSION

The estimated number of people in the affected area and vehicle's average speed are the most significant variables associated with the number of casualties in MV-IMCIs, helping to enable a timely estimation of the casualties.

Mass casualty, intentional vehicular trauma and anaesthesia

The use of motor vehicles to initiate mass casualty incidents is increasing in frequency and such events are called intentional vehicular assaults. Perpetrators are inspired by a range of terrorist ideologies or have extremist views, criminal intent, or mental health issues. Assaults using a motor vehicle as the principal weapon of attack are easy to launch and require little to no forward planning. This makes them difficult for police and security agencies to predict, prevent, or interdict. With the increasing frequency of intentional vehicular assaults, anaesthesiologists in various settings may be involved in caring for victims and should be engaged in preparing for them. This narrative review examines the literature on vehicle assaults committed around the world and provides an overview of the unique injury patterns and considerations for the pre-hospital, perioperative, and critical care management of victims of these mass casualty events. The article discusses planning, education, and training in an attempt to reduce the mortality and morbidity of intentional vehicular assaults.