*Mass Casulty and Blast Trauma*
By: OKmedic23
26 September 2004

Explosives can be categorized into two categories:

*High Order Explosives- TNT, C-4, Semtex, Nitroglycerin, Dynamite and Ammonium Nitrate Fuel Oil (ANFO).

*Low Order Explosives- Pipe Bombs, Gun Powder and Pure Petroleum based bombs

Both include ballistic and thermal injuries. High order explosive may also include blast wave injuries.


Blast Injuries may me caused by:

*Blast wave (overpressure)

*Secondary Blast Injury, caused by propelled objects

*Tertiary Blast Injury, being thrown into an object


The Blast Wave:

*Has a concussive effect

*3,000-8,000 meters/sec (5,000-14,000 mph)

*Affects tissues with air/tissue interface

*Distance from blast center greatly affects impact

*Tympanic Membrane ruptures at 5 psi above normal atmospheric pressure

*Pulmonary Injury at 10-15 psi above normal atmospheric pressure

*GI, Stomach and Large Bowel Injurie on account of air pockets

*"Blast Lung" simmilar to Pulmonary Contusion (internal bruising in lungs)

*Bloody Sputum

*Arterial air embolism


Secondary Blast Injury (OKC Bombing):

*Typically the exposed areas eg. head, neck etc.

*Consider the possibility of embedded foreign bodies


Tertiary Blast Injury:

*Deceleration Injury

*Thermal (usual 1deg flash burn)

*Toxins and Smoke


History has shown that of the persons that will present to the Emergency Department, 50 percent will show in the first hour. Double this figure and you should have a rough idea of how many you will see in the next 23 hours. Typically this first half will be less injured. They will usually arrive by private means. Only 25 percent of NYC-WTC 2001 victims arrived via EMS. Lesson, get them treated quickly, lacerations etc, and be prepared for the worst to still arrive in terms of severity.

Bombings are broken down into 3 Categories:

Immediate Structural Collapse - expect crush injuries, high fracture rates, and inhalation injuries.

Confined Space Bombings- expect higher rate of pulmonary blast injuries, pneumothoraxes, blast lung, tympanic membrane ruptures, higher rate of burns, and higher rate of solid organ injuries.

Open Air Bombings- increased rate of shrapnel or penetrating soft tissue injuries.

Most deaths will be immediate. ER deaths are statistically 1% or less. Usually the bottleneck in the ER will be the Chest Radiograph for screening of non critical victims.

All materials at this site not otherwise credited are Copyright © 1996 - 2004 Trip Williams. All rights reserved. May be reproduced for personal use only. Use of any material contained herein is subject to stated terms or written permission.