Page 114 - JSOM Summer 2022

Coagulopathy Associated With Trauma

A Rapid Review for Prehospital Providers

Jonathan Friedman, BSN, RN, FP-C ; Ricky Ditzel, BSHS, CCP-C, SO-ATP ;
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Andrew D. Fisher, MD, MPAS *
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ABSTRACT
The coagulopathy associated with trauma is a complex and The lethal triad is a combination of coagulopathy, acidosis,
convoluted process that is still poorly understood. However, and hypothermia, in which each component exacerbates the
there are recognized contributors to acute traumatic coagulop- others. The lethal triad is also described as iatrogenic due to
athy (ATC) and trauma induced coagulopathy (TIC) that are crystalloid fluid administration and inadequate hypothermia
universal. They are hypothermia, acidosis, and coagulopathy, prevention. Recently, hypocalcemia has been considered a dis-
also known as the lethal triad. Recently, with new understand- tinct part of iatrogenic coagulopathy secondary to blood prod-
ing of hypocalcemia’s role in trauma mortality, the term lethal uct administration containing citrate. In addition, patients
diamond has been coined to underscore calcium’s importance. often arrive hypocalcemic at the first role of care, thereby com-
Prehospital providers often unknowingly exacerbate ATC and pounding this issue. For many years, the best recommended
TIC with excessive crystalloid administration and poor hypo- prevention of the lethal triad in battlefield medicine was hy-
thermia prevention. This article will serve as an overview of pothermia prevention with the use of commercially manufac-
the physiologic and iatrogenic drivers of ATC and TIC, and tured external heating devices such as body warmers and fluid
will discuss how they can be prevented, assessed, and treated. warmers. More recently, there has been an increased use of
blood products – primarily whole blood – to address coagulop-
Keywords: lethal triad; critical care; prehospital; coagulopathy; athy and acidosis, along with trauma induced coagulopathy.
trauma; resuscitation; lethal diamond
Trauma-induced coagulopathy (TIC) is an overarching con-
cept with a spectrum of hypercoagulable and hypocoagulable
Introduction states and involves the exogenous (iatrogenic) and endogenous
(inherent) pathways (Figure 2). Acute traumatic coagulopa-
4–6
Traumatic injury and hemorrhage are the leading causes of thy (ATC) is a complicated aspect of the endogenous pathway.
death in the United States for ages 44 and under. Furthermore, The drivers of ATC are poorly understood, however, there
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hemorrhage is the leading cause of potentially preventable are basic mechanisms that are universal. This review, while
death in combat. In the US, the median time to death from only touching the surface of coagulopathy in trauma, is meant
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hemorrhage after hospital admission is 2 hours. To mitigate to increase understanding of the coagulopathy phenomenon
mortality and morbidity, there is an urgency to identify and in trauma and how treatments and resuscitation efforts are
treat life-threatening injuries and control hemorrhage. Inad- interrelated.
equate treatment of patients suffering from hemorrhage may
result in the lethal triad and its deleterious effects (Figure 1). ATC occurs within the first 30 minutes after injury and ex-
acerbates hemorrhage, whereas TIC can happen at any time
post trauma. First described in 2003, ATC exacerbates hem-
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orrhage in approximately 25% of severely injured patients
presenting with ATC. Classically, ATC was associated with
8,9
consumption of coagulation factors, acidosis, dilutional ef-
fects of crystalloids, and hypothermia.
FIGURE 1 The Both TIC and ATC may be measured using rotational throm-
lethal triad. boelastometry (ROTEM) (TEM International GmbH, https://
werfen.com/de/de) or thromboelastography (TEG) (Haemon-
etics, https://www.haemonetics.com/) and may be character-
ized by reduction in clot generation and strength, as well as
prolonged clotting times. 8,10 However, the overall incidence
and true definition of TIC is clouded due to the varying labo-
ratory values in published studies. 4

*Correspondence to anfisher@salud.unm.edu
1 Jonathan Friedman is affiliated with the Special Operations Medic Coalition, Kinston, NC, and a registered nurse and critical care paramedic.
2 Ricky Ditzel is affiliated with the Special Operations Medic Coalition, Kinston, NC, and is a postbaccalaureate student at Columbia University,
New York, NY. Dr Andrew D. Fisher is a physician affiliated with the Department of Surgery, University of New Mexico School of Medicine,
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Albuquerque, NM, and the Medical Command, Texas Army National Guard, Austin, TX.
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