This document discusses mass casualty and terrorism incidents from a medical perspective. It begins by outlining the levels of hospital involvement needed to respond, from the emergency department being busy initially to operating theaters, critical care, and general wards being involved for prolonged periods over weeks to months. It notes differences and similarities between terrorism incidents and other disasters. Key aspects discussed include communications throughout response, situation awareness, leadership, triage challenges when most severely injured may not arrive first, and the mechanisms of blast injury particularly for bombs including primary, secondary, tertiary and quaternary effects. Resources on emergency preparedness, resilience and response as well as primers on mass trauma and blast injuries are provided.

1. Mass Casualty and Terrorism
Mark Midwinter MD FRCS
Professor Clinical Anatomy
School of Biomedical Sciences

3. https://www.nationaltraumacentre.nt.gov.
au/

8. https://www.start.umd.edu/gtd/

9. Threat
http://economicsandpeace.org/wp-
content/uploads/2015/11/Global-Terrorism-Index-
2015.pdf

11. The problem of perspective
Tension: individual versus the greatest benefit

12. • The emergency department will be very busy in
the initial stages of a hospital response.
• Progressively, deeper parts of the hospital
become involved (operating theatres, critical care,
general wards etc.)
• Duration of activity increases:
• Hours to weeks for operating theatres,
• Days to weeks for critical care
• Weeks to months for general wards.
• Associated services (catering, sterilizing services,
laundry suppliers, administrative support) will also
have higher activity levels for a prolonged period
following an incident.

14. Terrorism versus other disasters
Differences and similarities:
• Targeted
• Threat
• Location
• Mechanisms
• Hostile patients
• Contamination

15. Communications – along the whole pathway.
Dissemination
Situation awareness
CRM:
• Leadership
• Followership

16. The most severely injured do not necessarily arrive
first.
Capacity predications are fluid at best.
Triage

17. • The four basic mechanisms of blast injury are termed
as primary, secondary, tertiary, and quaternary.
• “Blast Wave” (primary) refers to the intense over-
pressurization impulse created by a detonated HE.
• Blast injuries are characterized by anatomical and
physiological changes from the direct (or reflective)
over-pressurization force impacting the body’s surface.
• The “blast wave” (over-pressure component) should be
distinguished from “blast wind” (forced super-heated
air flow).

20. Blast Brain Injury
The blast wave affects the brain immediately upon impact with the skull. Pressure in the
brain returns to normal after only a few milliseconds, but brain motion can occur for
hundreds of milliseconds after impact.
Blast Wave Transmission milliseconds
Brian l. Edlow, Massachusetts General Hospital; from the Journal of Neuropathology and Experimental
Neurology

21. Emergency
Preparedness,
Resilience and
Response (EPRR)
https://www.england.
nhs.uk/ourwork/eprr/
gf/

22. Resources
https://www.cdc.gov/masstrauma/preparedness/primer.pdf
• https://www.rcemlearning.co.uk/references/blast-
injuries/
• https://www.acep.org/blastinjury/#sm.001phe4xy1cv9dpb10idb4f
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