Opinion

VIEWPOINT
Implications of Combat Casualty Care
for Mass Casualty Events

Eric A. Elster, MD
Norman M. Rich

Department of Surgery,

Uniformed Services

University of the Health

Sciences, Bethesda,

Maryland, and Naval

Medical Research

Center, Silver Spring,

Maryland.

Frank K: Butler, MD

United States Army

Institute of Surgical

Research, Joint Base

San Antonio, Ft Sam

Houston, Texas.

Todd E. Rasmussen, MD

Norman M. Rich

Department of Surgery,

Uniformed Services

University of the Health

Sciences, Bethesda,

Maryland, and United

States Army Institute of

Surgical Research, Joint

Base San Antonio, Ft

Sam Houston, Texas.

Corresponding
Author: Eric A. Elster,

MD, Department of

Surgery, Uniformed

Services University of

the Health Sciences,

4301 Jones Bridge Rd,

Bethesda, MD 20814

([email protected]).

Violence from explosives and firearms results in mass
casualty events in which the injured have multiple pen-
etrating and soft tissue injuries. Events such as those in
Boston, Massachusetts; Newtown, Connecticut; and Au-
rora, Colorado, as well as those in other locations, such
as Europe and the Middle East, demonstrate that civil-
ian trauma may at times resemble that seen in a com-
bat setting. As the civilian sector prepares for and re-
sponds to these casualty scenarios, research and trauma
practices that have emerged from the wars in Afghani-
stan and Iraq provide a valuable foundation for respond-
ing to civilian mass casualty events. Several lessons
learned by the US military were implemented duringthe
response to the bombings in Boston in April of this year.

Military research has found thatapproximately 25%
of persons who die as a result of explosive or gunshot
wounds have potentially survivable wounds.’ These in-
dividuals have injuries that are not immediately or nec-
essarily lethal and have a chance to survive if appropri-
ate care is rendered in a timely fashion. The military has
learned that implementation of evidence-based, clini-
cal practice guidelines can reduce potentially prevent-
able death.^ Certain aspects of these lessons also apply
to multiple casualty scenarios in civilian settings.

The care of wounded military service personnel is
based on an integrated trauma system and involves
timely point-of-injury intervention, coordinated pa-
tient transport, whole blood or blood component-
based resuscitation, and initial operatingfocused on con-
trol of hemorrhage and optimizing patient physiology.
Referred to as damage control surgery, this approach in-
volves abbreviated techniques instead of longer defini-
tive operations. The principles of combat casualty care
should be considered in 3 phases: point of injury, dur-
ing transport to the hospital, and hospital-based treat-
ment. The wars have highlighted the importance of a
trauma system to coordinate these phases and im-
prove survival. In implementing this strategy, the mili-
tary developed the Joint Trauma System, which is de-
signed to provide wounded troops an optimal chance for
survival and recovery.

Care at the Point of Injury
The majority of wartime deaths occur in the out-of-
hospital setting. The point of injury component of care is
termed tacticalcombatcasualtycare. During the past de-
cade, this phase has been transformed to introduce and
integrate elements of medical care with military tactics.
Combat units are now trained in tactical combat casualty
care, a strategy that has reduced preventable death.^’^
Kotwal et aP reported that the 75th Ranger Regiment’s
implementation of a system based on tactical combat ca-
sualty care was associated with a historically low 3% inci-

dence of preventable death. Moreover, none ofthe regi-
ment’s 32 fatalities died of preventable causes duringthe
out-of-hospital phase of care. The critical elements ofthe
protocol include early control of hemorrhage using tour-
niquets for extremity bleeding and hemostatic dressings
for bleeding not amenable to tourniquets.

Care During Transport
Evacuation is the next step in the continuum. Findings
from military research have shown improved survival as-
sociated with the use of more advanced en route care
capability. Mabry et al’* demonstrated a 66% reduction
in mortality among patients evacuated by critical care
flight paramedic teams (16 deaths among 202 pa-
tients) compared with casualties transpoited by basic
emergency medical technicians (71 deaths among 469
patients). The survival benefit was attributed to higher
levels of trainingand experience amongflight paramed-
ics. Morrison et al^ extended these observations in a
study of injured military personnel evacuated by the
United Kingdom’s physician-led platform (aircraft or air-
frame used to transport patients) referred to as the medi-
cal emergency response team-extended (M£RT-£).nths
report, there was a 33% reduction in mortality in the
most severely injured who underwent evacuation with
MERT-E (47 deaths among 385 patients) compared with
those evacuated with conventional platforms (36 deaths
among 198 patients). Many ofthe advanced evacua-
tion platforms include the capacity to administer blood
and blood components and to provide other lifesaving
interventions priorto reachingthe hospital. The person-
nel on these advanced platforms may be acute care nurse
practitioners, flight nurses, critical care flight paramed-
ics, or critical care trained physicians.

Hospital-Based Care
The receiving trauma center provides the third phase of
care. The US military’s hospital-based experience with
multiple casualty scenarios following single explosive
events was documented in the 2009 Balad Air Base (in
northern Iraq) report,® which described strategies used
to mitigate morbidity and mortality in 50 injured pa-
tients following 3 consecutive explosive events and
quantified estimates of casualty surge capacity. Man-
agement ofthe most severely injured patients with com-
plex penetrating wounds included strategies of dam-
age control resuscitation; treatment of hemorrhagic
shock with whole blood or balanced ratios of blood com-
ponents such as plasma, platelets, and cryoprecipitate
instead of crystalloid solutions; and damage control sur-
gery. These approaches to combat casualty care are out-
lined in the Joint Trauma System clinical practice
guidelines.^

jama.com JAMA August 7,2013 Volume 310, Number S 475

Opinion Viewpoint

Damage control resuscitation is based on results of military re-
search showing a survival benefit associated with administration of
equal ratios of plasma, packed red blood cells, platelets, and more re-
cently tranexamicacid.^-^ Damage control surgery involves perform-
ing only necessary amounts of operating to control bleeding, de-
bride nonviable tissue, stabilize fractures, and restore extremity
perfusion. Application of damage control surgery means that more
definitive operations are delayed until initial resuscitation has been
completed. The Balad report also documented the value of parallel
operating, which involves having more than 1 surgical team simulta-
neously tendingtoa patient to reduce anesthesia and operative time.®
For example, a patient with extremity injuries as well as and head and
neck injuries may have 2 teams composed of general and orthopedic
surgeons operating on these different anatomic locations at the same
time. Although this strategy does not apply to all cases, it can be used
for patients with multiple extremity fractures or penetratingand soft
tissue injuries to several different anatomic locations.

The military has also demonstrated the effectiveness of oper-
ating on multiple patients simultaneously in a single operating room.^
During the surgical surges in Balad, Iraq, more than three-fourths of
initial operations (involving a total of 50 patients) were performed
in rooms with more than 1 patient without adverse outcomes and
an overall 8% mortality. Practices like these demonstrate how space,
personnel, operating room tables and supplies, and anesthesia equip-
ment can be used effectively to perform lifesaving operations at a
pace greater than that of routine conditions.

The Balad report projected that three-quarters of patients in-
jured enough to require admission to the hospital would need an op-
eration and that nearly 4 procedures would be required per opera-
tion to manage penetrating injuries.® Findings from the US military
demonstrated that 110 procedures were performed during 40 op-
erations on 38 patients in the first 24 hours. The report also showed
that a balanced, blood component-based resuscitation was achiev-
able in the setting of a multiple-casualty event. The report esti-
mated that an average of just more than 3 units of packed red blood

cells, plasma, and platelets would be required per hospitalized ca-
sualty. The report also characterized intensive care unit and venti-
lator requirements, demonstrating that 1 nurse and 1 ventilator would
be anticipated for every 2 admitted casualties. The Balad report con-
firmed that many patients injured during explosive events re-
quired multiple operative interventions (191 procedures were per-
formed during 75 operations, translating to 3.8 procedures per
patient) in the days after the initial or index procedure (ie, a second-
ary wave of operating).®

Lessons From Wartime Trauma Care
These lessons from the wars in Afghanistan and Iraq are a product of
the nation’s investment in military trauma care and combat casualty
care research. However, few military clinical practice guidelinesare the
result of standard, randomized clinical trials. Instead, these lessonsare
the result of a process of focused empiricism, or by “identifying what
works and what does not, refining it over time and embracing a cul-
ture of continuous process improvement.”‘” This pragmatic ap-
proach adopted for military combat casualty care has allowed for rapid
adoption of lifesaving strategies through practical methods. In this con-
text, the evidence base supporting the milita ry’sdinical practice guide-
lines is driven by the results of basic science, translational large ani-
mal research, and retrospective cohort analyses. Despite the lack of
randomized trials, the net outcome of the military’s approach and other
improvements in trauma care is the lowest case fatally rate for US ser-
vice personnel recorded in the history of war.

As the United States and other nations continue to prepare for
casualty scenarios from explosives or mass shooting events involv-
ing civilians, lessons from wartime trauma careand resuscitation may
be helpful in planning responses. The trauma practices that have re-
sulted from more than a decade of combat casualty care and re-
search are transferable to the civilian world. Continuing to trans-
late these lessons from war should provide a foundation to help
reduce mortality and morbidity among civilians injured in future mass
casualty events.

ARTICLE INFORMATION

Conflict of Interest Disclosures: All authors have
completed and submitted the ICMJE Form for
Disclosure of Potential Conflicts of Interest and
none were reported.

Disclaimer: The views expressed in this article are
those of the authors and do not reflect the official
policy of the US Departments of the Army, Navy, or
Defense: the Federal Bureau of Investigation: the
US Department of Justice, or the US government.

Copyright Protection: Our team comprises military
service members and employees of the US
government. This work was prepared as part of our
official duties. Title 17 US Code 105 provides that
“Copyright protection under this title is not
available for any work of the US government.” Title
17 US Code 101 defines US governmental work as
work prepared by a military service member or
employee of the US government as part ofthat
person’s official duties.

Additional Contributions: We thank David S.
Wade, MD, chief medical officer for the Federal
Bureau of Investigation, for his for support and
insightful guidance on this article, for which he
was not compensated beyond his normal salary.

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