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SECTION 2
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I mm ed iate Management and
Diagno st ic A pp roaches
55
5
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Prehospital Management of
Vascular Injury
ROBERT H. JAMES and JASON E. SMITH
Introduction
Major hemorrhage is the leading cause of preventable death
in both civilian and military trauma patients.
since the beginning of the twenty-rst century improvements have been made in the care of trauma patients with
major hemorrhage. For the purposes of this chapter the
terms vascular injury and major hemorrhage will be used
interchangeably.
These improvements are, perhaps, best demonstrated
by examining the survival of wounded military personnel
during recent operations in Iraq and Afghanistan. The New
Injury Severity Score (NISS) associated with a 50% risk of
death increased from 32 to 60 over the period 2003–12
(Fig. 5.1).3 This improvement in survival is largely attributable to advances in the care of patients with major
hemorrhage.
In order to effectively manage vascular injury in the
prehospital environment, there are two key components.
Firstly (and most crucially), where possible, stop the bleeding. Secondly, mitigate blood loss with an appropriate volume replacement strategy, ideally with blood and blood
products, which may include the use of pharmacological
adjuncts. The advances seen during recent conicts were
due to several factors, but these can be grouped into these
two key areas. The near universal training in, and availability of, devices such as tourniquets (TQs) and hemostatic
dressings allowed the control of hemorrhage at the earliest
possible time, and the forward deployment of medical teams
with the capability to provide advanced resuscitative techniques ensured that replacement of lost blood volume was
managed in line with the latest resuscitation strategies.
In this chapter we will discuss the lessons learned during these conicts and attempt to translate their relevance
to the wider readership of this book. We will also explore
potentially life-saving techniques that have continued to
evolve since the cessation of major combat operations in
Afghanistan and those that may continue to evolve in the
future. In order to do this, we will consider bleeding coming from three distinct pseudoanatomical zones: extremity
hemorrhage, junctional hemorrhage (the groins, axillae,
and neck) and noncompressible torso hemorrhage (NCTH);
and discuss the current and future prehospital management of each of these types of bleeding. We will also briey
discuss the management of maxillofacial hemorrhage,
which can be life-threatening and requires specic, prehospital, management steps but does not t neatly into these
categories. Finally, we will analyze current thinking related
to volume replacement in the bleeding trauma patient,
explore the scientic rationale behind this thinking, and
attempt to provide some practical guidance for those trying
to resuscitate bleeding trauma patients.
56
3
1,2
However,
4
Stopping the Bleeding
EXTREMITY HEMORRHAGE
Principles
The extremities are the most commonly injured anatomical regions in those patients wounded on the battleeld.5 In
patients with battleeld injury in more than one body area,
82% will have an injury to at least one limb.5 As a result
of this, much of the guidance pertaining to management
of exsanguinating extremity injury is from military experience and literature. Although caution should be used when
translating experience from one sphere to another, a mangled or amputated limb caused by a motor vehicle collision
or industrial accident requires similar management to that
caused by an improvised explosive device (IED).6 Equally it
should be noted that “military” mechanisms of injury can
be experienced in civilian practice.
During American combat operations in Vietnam, exsanguination from wounded extremities was the most common cause of preventable death.8 This was in contrast to
the experience of American Special Forces personnel during combat operations in Somalia in the late 1990s. Here
US special forces used TQs for patients with catastrophic
extremity hemorrhage, which was not standard practice
during the Vietnam war or among the wider military or
civilian populations in the late 1990s. Case reports from
the conict credited the use of TQs with preventing death
from exsanguination.9 The potential value of TQ use was
recognized and in the later conicts in Iraq and Afghanistan, there was a resurgence in the use of TQs for extremity
injury, along with improvements in design. The UK military
were also early adopters of the new style TQs. In April 2006
they became personal issue for all UK personnel deploying
to operational areas. This adoption of TQs was one part of
a larger paradigm shift in care for battleeld casualties from
the familiar “ABC” to a revised “<C>ABC”.10 This placed the
control of catastrophic hemorrhage as the primary consideration when treating a wounded casualty. Reviews of the
use of tourniquets, as part of this new paradigm, by both
the British and American militaries again found them to be
life-saving.
The UK military’s approach to the management of
extremity injury was further conceptualized in a hemostatic
ladder (Fig. 5.2).13 This ladder covers the whole spectrum
of the management of catastrophic hemorrhage, including
in-hospital care. It should be noted that only the rst four
rungs on the ladder are applicable to prehospital care and,
when viewed through today’s lens, the ladder could be considered to be incomplete or even incorrect due to the omission of tranexamic acid and the inclusion of recombinant
activated Factor VII (rFVIIa).
11,12
7
14,15
Notwithstanding these
5 • Prehospital Management of Vascular Injury 57
1
NISS
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
Probability of Survival
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0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
Fig. 5.1 Cumulative probability of survival versus new injury severity score (NISS) for patients treated in Afghanistan and Iraq, 2003 to 2012. (With
permission from Penn-Barwell, et al. Improved survival in UK combat casualties from Iraq and Afghanistan: 2003–2012. J Trauma and Acute Care Surg.
2015;78(5):1014–1020.)
15 30
45 60 75
Year
concerns, the principles of the hemostatic ladder remain
valid and provide a good representation of the care provided
to injured personnel, and remain as a guide to the management of casualties today.
A stepwise approach starting with direct pressure and
elevation, using a First Field Dressing (FFD) or equivalent, is
usually the rst technique that should be used in the management of bleeding extremity injuries. If necessary, this
can then be followed by the use of hemostatic agents (see
later). If these measures fail to control hemorrhage, a TQ
should then be applied.
In addition to allowing easy conceptualization of the
principles of management of catastrophic hemorrhage,
there are other great strengths to this model. First, there
is an acknowledgement that there are times when the
stepwise approach advocated should not be followed.
One example is during “care under re” (CUF) when a TQ
should be applied immediately due to the tactical situation.
However, it can be extrapolated that there are also clinical
situations where moving straight to TQ application may
be appropriate. This may be due to the state of the limb
itself, i.e., mangled or amputated with catastrophic hemorrhage, or due to competing priorities in the care of the
patient, e.g., concomitant airway obstruction or complete
ventilatory failure requiring emergency management. In
other words, there are occasions when the use of a TQ
is the most expeditious way to manage exsanguination
Fig. 5.2 The hemostatic ladder for the management of hemorrhage.
rFVIIa, Recombinant activated Factor VII. (With permission from
Moorhouse I, et al. A realistic model for catastrophic external
hemorrhage training. J R Army Med Corps. 2007;153(2):99–101.)
and thus should be used in order to allow timely management of other injuries, even if a more time-consuming
approach, such as direct pressure with or without hemostatic gauze, may also work.
This is a situation where expert clinical judgement is
required. Another example of when it may be advisable to
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jump some rungs of the ladder is if the number of patients
outmatches the number of clinicians available to deal with
them – the National Ambulance Resilience Unit recommends the use of TQs to manage extremity hemorrhage in a
major incident.16 The nal situation where TQ use is appropriate, without escalating through the hemostatic ladder,
is when operating in a chemical, biological, radiological,
or nuclear (CBRN) environment. Here the requirement
to keep the casualty as well protected as possible from the
CBRN hazard, as well as the encumbrance for the clinician
of operating in personal protective equipment (PPE), necessitates the use of TQs.
17
In addition, the decision to use a TQ should be reviewed at
the earliest appropriate point and de-escalated back down
the hemostatic ladder if appropriate.
13
Practicalities
Simple measures often save lives. Direct pressure can often
stop signicant bleeding, at least until a more denitive
means of controlling the bleeding is possible. If simple
direct pressure is not successful, hemostatic dressings
should be considered. This is likely to be especially helpful
in situations where there is a wound cavity to pack, e.g.,
a gunshot wound. UK military guidelines suggest a twoperson approach to the application of their hemostatic
dressing of choice (Celox). One person removes the FFD,
which was applied in order to manage the wound with
direct pressure, as the other tightly packs the hemostatic
dressing into the wound cavity. The rst operator then
reapplies direct pressure through another FFD for three
minutes.18 The direct pressure here is key: the hemostatic
dressing should be seen as an adjunct to direct pressure,
not as an alternative. Further discussion about hemostatic
dressings can be found below in the “Junctional Hemorrhage” section.
As discussed previously, TQs have been shown to be life-
11,12
saving.
Whereas the manner of application depends on
the exact model of TQ used, certain principles are ubiquitous (Box 5.1).
When TQs are applied for the correct indication, the risk
of ischemic injury to the limb is outweighed by the risk of
death from exsanguination. It should be noted that arterial
Box 5.1 General Principles for Applying an
Arterial Tourniquet (TQ)
1. Application of a TQ should occur in:
a. Limb amputation with bleeding
b. Catastrophic hemorrhage
c. In the additional situations outlined in the text
2. Unless involved in CUF or in a CBRN environment, apply the TQ
5–7.5 cm above the bleeding site directly to skin.
3. Tighten the TQ until bleeding stops. Remember, some oozing
from bone ends may continue, but this will be low pressure
and amenable to pressure control.
4. If bleeding is not controlled or the TQ is being applied for an
above-knee amputation, apply a second TQ proximal to the
first one.
5. Note TQ application time.
CBRN, Chemical, biological, radiological, or nuclear; CUF, care under fire.
19
TQs are routinely used in elective surgery. It should also be
noted that injury to the limb is rare if a TQ is in place for
less than 2 hours, although this evidence relates to elective
surgical patients and may not be applicable to hypovolemic
trauma patients.
6 hours is likely to lead to muscle damage necessitating
amputation.
20,21
Application of a TQ for longer than
21
Appropriate removal of a TQ is another area for consideration – see Box 5.2 for the key principles. If the TQ has
been in place for more than 6 hours, removal should only be
undertaken with cardiac monitoring and with appropriate
equipment for resuscitation to hand.
JUNCTIONAL HEMORRHAGE
Principles
Junctional hemorrhage, or bleeding from a junction
between the torso and the extremities, is by denition not
amenable to traditional extremity TQ use. This is either
because it is not possible to get proximal to the wound in
order to apply a TQ (in the axillae and groins) or because an
ischemic zone distal to the TQ is not feasible (in the neck).
Once again much of the data and experience related to the
management of injuries to these areas comes from military
evidence and experience. A review of US fatalities during
Operations IRAQI FREEDOM (OIF) and ENDURING FREEDOM (OEF) found that by the end of OEF junctional hemorrhage had surpassed extremity hemorrhage as the leading
cause of potentially avoidable death from compressible hemorrhage.1 These deaths are avoidable because, although not
amenable to TQ use, bleeding in junctional areas is easily
accessible and potentially compressible. Therefore, relatively
straightforward treatment options, which can be employed
by nonspecialist physicians and, indeed, by nonvocational
medics, exist for managing hemorrhage in these areas. This
is particularly the case with the widespread adoption of
hemostatic agents. The widespread use of these dressings,
along with the resurgence of TQs, must be considered one
of the positive legacies of these conicts.
Practicalities in the Management of Junctional
Hemorrhage
There are additional complexities in managing vascular
injury in the neck. Therefore, the management of the neck
will be considered separately to the management of bleeding in the axillae and groins.
Box 5.2 Principles for Removal of an Arterial
Tourniquet (TQ)
1. An alternative method of hemorrhage control should be in
place prior to removal of a TQ.
2. This should only be undertaken in a controlled environment
where the casualty can receive careful assessment and rapid
treatment if they were to deteriorate.
3. Do not remove the TQ; merely loosen it.
4. If alternative methods of hemorrhage control are not successful, re-tighten the TQ.
18
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Axillae and Groins. The basic principles of controlling
hemorrhage from these areas again follow the hemostatic
ladder in Fig. 5.2, although TQ use is not an option. There is
little difference in the requirement for direct pressure with
or without the addition of a hemostatic dressing. However,
the severity of injuries caused by IED blasts, especially
during the conict in Afghanistan, sometimes exceeded the
capacity for management by direct pressure ± hemostatic
dressing. As such, novel techniques and devices have been
investigated and, in some cases, have begun to be used.
Neck. Vascular injury in the neck occurs in 3% of blunt
and 20% of penetrating craniocervical injuries.
22,23
The
number of important anatomical structures in the neck
makes this a unique and challenging area in which to
manage vascular injury. There is a spectrum of clinical
syndromes that need to be considered:
1. Injury to neck vessels may lead to exsanguination due to
external catastrophic hemorrhage.
2. Contained hemorrhage from an injury to a neck ves-
sel, especially an artery, may lead to development of a
hematoma that compresses other structures in the neck,
crucially the airway, leading to life-threatening airway
obstruction.
3. Dissection of neck vessels may lead to neurological
sequelae, ranging from subtle ndings on neurological
examination to profound decit or stroke.
To discuss the management of each of these syndromes
in turn:
1. For external catastrophic hemorrhage, direct pres-
sure ± a hemostatic dressing is again the approach
of choice. However, the pressure applied may in itself
cause airway compromise. Therefore, if the option to
denitively secure the airway (with a cuffed tube in the
trachea) is available, then this should be considered as
part of the initial management. An additional or alternative method for control of hemorrhage is Foley catheter balloon tamponade. This requires the insertion of
a Foley catheter into the wound track and the ination
of the balloon with 10 to 15 mL of water. The catheter
is clamped to ensure there is no bleeding through the
lumen of the catheter. It may then be advisable to close
the neck wound around the catheter.22 Successful cessation of bleeding in as many as 85% of patients has
been reported with this technique, although it should
be noted that in this case series the neck wounds were
caused by a low velocity mechanism.22 There is a possibility of patient deterioration following the insertion
of the balloon (usually due to excessive vagal stimulation), so if this happens the balloon should be deated,
and alternative methods of hemorrhage control
sought.
24
2. The rst requirement for the successful management
of neck vascular injury with contained hemorrhage is
a high index of suspicion. Very small entry wounds can
cause signicant vascular injury. The symptoms and
signs of neck vessel injury may at rst be subtle. Potential indicators of a neck vessel injury are a wound deep
to platysma, hoarse voice, expanding hematoma, pulsatile mass, and stridor.
Patients with these signs, especially expanding hematoma or stridor, will require denitive airway control.
Irrespective of the difculty that this airway is likely to
present, there is a strong argument for prehospital intubation of these patients. This is true despite the lack of
access to both additional support (e.g., from anesthetics and ENT) and the full complement of difcult airway
equipment. Exceptions to this rule are if transfer time
to a facility equipped to manage the injury is extremely
short or appropriately skilled and equipped personnel
are not available to denitively secure the airway prehospital.24 This is because these airways will, with time,
deteriorate, sometimes rapidly. This is another decision
requiring expert clinical judgement.
When considering intubating these patients, the most
experienced and skilled intubator should undertake the
rst attempt.25 The patient should be optimized and positioned, and all appropriate procedures to ensure the highest chance of rst pass success should be undertaken,
e.g., adequate paralysis, the use of checklists, and use of
a bougie.25 The intubator should be prepared for blood
in the airway and, as such, adequate suction should be
available. Equally, all members of the team should be
prepared for a failed intubation and a well-rehearsed and
robust plan for this eventuality must be in place.
25
3. Prehospital management of vessel dissection is limited
to having an index of suspicion, supportive measures
including Prehospital Emergency Anesthesia (PHEA)
dependent on the patient’s neurological state, and transfer to an appropriate facility capable of managing the
patient’s holistic care.
Hemostatic Dressings
We have already introduced the subject of hemostatic dressings, so will now explore in more detail what these items are
and examine the pros and cons of individual formulations.
Hemostatic dressings can be grouped by their mecha-
nism of action into26:
1. Those that concentrate clotting factors
2. Muco-adhesive agents
3. Procoagulant factor supplements
Factor concentrators were the original hemostatic
agents. They are presented as loose or encapsulated granules and act by rapidly absorbing water, bringing platelets
and clotting factors into closer contact with each other and
therefore stimulating coagulation. The agent most commonly used initially was QuickClot. However, there were
concerns about an exothermic reaction from the activated
agent causing burns, and also concern about difculty
removing the product from the wound further along the
care pathway, and so the use of this agent has declined.
27
Muco-adhesive agents form a seal around the bleeding
site and thus encourage coagulation.26 These products are
usually made from chitosan impregnated gauze and include
Celox and HemCon.
Procoagulant factor supplements such as QuickClot
Combat Gauze deliver a high local concentration of clotting
factors and thus activate the coagulation cascade.
26
Agreed criteria that make an ideal hemostatic dressing
can be found in Box 5.3.
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Box 5.3 Features That Make an Ideal
Hemostatic Dressing
1. The ability to stop large vessel bleeding within 2 minutes
2. Approved by national medical device/drug licensing agency
3. Effective on wounds not amenable to a tourniquet
4. Flexible and easily removable
5. Be ready to use without mixing or preparation
6. Be simple to apply with minimal training, including by the
casualty
7. Be lightweight and durable
8. Have a minimum 2-year shelf life and stable at extremes of
temperature
9. Be safe to use
10. Be relatively inexpensive
11. Be nontoxic with no side-effects
12. Is biodegradable and bioabsorbable
Three recent systematic reviews have examined the ef-
cacy of the different types of hemostatic dressing.
27,28
29–31
All
were narrative reviews due to the heterogeneity of included
studies, and all found that the hemostatic dressings were
effective. However, evidence comparing one particular formulation to another was both scarce and contradictory.
Complex or Novel Options
Given that there are described instances of hemostatic
dressing failure, further options are potentially required for
the management of junctional hemorrhage. These options
can again be considered in two broad camps. Those methods relying on local effect to control hemorrhage and those
methods aimed at gaining proximal control of bleeding.
Fig. 5.3 The XSTAT 30 from RevMedX. (Personal correspondence James/
Musho. With Permission.)
Methods Relying on Local Effect. Several devices are
either being trialed or have recently started being used
clinically for the management of junctional hemorrhage.
Most are unlikely to be of use in managing vascular
injury in the neck, although there are promising results
for their use in axillary or groin hemorrhage. Whereas
the devices themselves are new, the principle they rely on
is the augmentation of direct pressure with or without the
additional use of hemostatic dressings.32 One of the more
novel solutions is a device, much like a large syringe, which
allows chitosan-soaked, cellulose sponge to be injected into
an axillary wound (Fig. 5.3) and then secured with normal
bandages. This has Food and Drug Administration (FDA)
approval for use in axillary wounds, and has undergone
initial clinical trials with promising results, but intrathoracic,
intrapelvic, or intraabdominal use is contraindicated.
33,34
Other devices (the Combat Ready Clamp [CRoC], the
Junctional Emergency Tool [JETT], the SAM Junctional
Tourniquet [SAM-JT], and the Abdominal Aortic Junctional
Tourniquet [AAJT]) use clamps or inatable bladders to provide direct pressure over the wound. There have been some
case reports of their use in both axillary and groin hemorrhage with good effect. Many of the devices were deemed to
be too bulky or fragile to be an ideal solution for prehospital use, but the SAM-JT (Fig. 5.4), essentially a SAM pelvic
binder with the addition of an inatable bladder, received
positive feedback from US armed forces medics in a preclinical trial.
35
Fig. 5.4 The SAM JT. A junctional tourniquet. (With permission from van
Oostendorp SE, et al. Prehopsital control of life-threatening truncal and
junctional hemorrhage is the ultimate challenge in optimizing trauma
care; a review of treatment options and their applicability in the civilian
trauma setting. Scand J Trauma Resusc Emerg Med. 2016;24:110–123.)
The nal device worthy of mention is the iTClamp. This
is unique in that it may be used in neck wounds as well as
groin or axillary wounds. It is a mechanical clamp with
needle-like teeth that is applied to a wound and approximates the skin edges in order to tamponade bleeding. In
one trial, when used in this manner, it failed to adequately
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control bleeding from a neck wound, but when the cavity was packed with hemostatic gauze and the iTClamp
re-applied, bleeding was controlled.36 There are also case
reports of successful use in groin hemorrhage.
37,38
Methods for Gaining Proximal Control of Blee-ding.
There is cross-over between these techniques and the
techniques used for management of NCTH. Here a discussion
of the implications of the use of these methods in junctional
hemorrhage will be undertaken, with further detail in the
management of NCTH provided in the relevant section.
The rst and most widely used prehospital technique is
resuscitative thoracotomy (RT). In the management of groin
hemorrhage, the aim of RT is to access and compress the
descending aorta. This is usually only performed once the
patient has suffered a traumatic cardiac arrest (TCA). The
role of prehospital RT in penetrating trauma, especially stab
wounds in the “cardiac box,” is well-established in both the
literature and practice.
39,40
A simple technique for opening
the chest using the “clamshell” approach is advocated
giving excellent exposure to the thoracic contents, although
the most cranial structures are still difcult to access.41
Notwithstanding the consensus regarding prehospital RT
for penetrating trauma, the situation in blunt injury or for
obtaining proximal aortic control in groin hemorrhage
is controversial, with resuscitative endovascular balloon
occlusion of the aorta (REBOA) being the more commonly
described technique for achieving hemorrhage control.42
This position contrasts somewhat with the military evidence.
In his review of RT following wartime injury, Morrison
reports 21.5% survival following RT; just over 46% of
these patients had an extremity injury with an abbreviated
injury score greater than 2, and 97% of them had aortic
control as part of their resuscitation.43 These data suggest
that RT for exsanguinating junctional hemorrhage may
not be futile. However, it should be noted that this study
describes in-hospital resuscitative thoracotomy.43 They found
worse survival in those patients sustaining cardiac arrest
prehospital (0%) compared to those arresting en-route to a
medical treatment facility (MTF) (10%) or arresting within
the MTF (42%). However, they also found that survivors had
a signicantly shorter time from arrest to thoracotomy (6.15
vs. 17.7 minutes).43 Patients in this case series had to wait
until ED arrival for thoracotomy to be undertaken. Although
Morrison suggests that RT in patients arresting in the eld
is futile, it is difcult to ascertain whether it was the arrest
in the prehospital environment that led to poor outcomes or
the delay in thoracotomy being performed, and as such we
cannot conclude from this paper whether prehospital RT
would have been of benet or whether it should necessarily
preclude the use of prehospital thoracotomy for control
of junctional hemorrhage.43 As such it is important to be
realistic about the likely success of prehospital RT and be
cognizant of the reduced resources available to clinicians
in the prehospital environment, the relative lack of surgical
expertise of prehospital physicians (who are usually not
surgeons) compared to in-hospital surgeons, and the less
favorable environment in which prehospital physicians are
forced to operate. Further evidence guiding TCA management
suggests that RT should be part of the management of patients
with TCA, many of whom will have suffered exsanguinating
junctional hemorrhage, and not merely viewed as a lastditch attempt in those destined to die.
44
The timing of prehospital RT is also an area worthy of
discussion. Many patients in TCA are in fact in a low cardiac
output state (LCOS).45 Thus ascertaining how far into their
apparent TCA thoracotomy should be undertaken is challenging. Traditionally, prehospital RT is only undertaken in
patients in TCA, as dened by a lack of a central pulse. However, the disease process may already be very advanced by
this time, resulting in a pathophysiological and biochemical
milieu that is resistant to attempts at resuscitation. There
certainly seems to be some physiological rationale to intervening earlier in patients in whom RT may be the denitive
procedure in reversing their disease process. Equally this is
supported by the literature base, with reduced time from
arrest to RT associated with improved survival.
43
As described previously, the use of REBOA instead of RT
for proximal aortic control has been advocated by various
authors. A more detailed discussion of REBOA is available
in Chapter 11, but we will mention the specic prehospital implications of REBOA. It has only been performed
in the prehospital environment by one service, London’s
Air Ambulance (LAA). They have demonstrated that with
the correct equipment and training, it is feasible to undertake REBOA in the civilian prehospital setting.46 Prehospital REBOA is limited to zone 3 placement only (where the
REBOA balloon is landed between the caudal renal artery
and the aortic bifurcation). As such there is only prehospital
experience of using REBOA for pelvic or more distal hemorrhage. Its use in the prehospital environment is challenging.
There is a failure rate of up to 32%, and signicant concerns
about the risk of arterial thrombus formation exist wherever
REBOA is carried out as a percutaneous technique.46 However, in case series those patients in whom REBOA was successful had an improvement in systolic BP of 66 mm Hg, and
both prehospital cardiac arrest and death from exsanguination were signicantly reduced (0% vs. 50% P = .021; 0% vs.
67% P = .004, respectively).46 There was also a suggestion
of improved survival (62% vs. 33%), although this failed to
reach statistical signicance (P = .350) and due to the study
design attributing this to REBOA, is not appropriate.
46
NON-COMPRESSIBLE TORSO HEMORRHAGE
Bleeding within the torso is arguably one of the greatest
challenges facing prehospital providers. To facilitate the
discussion of this pathology, it can be subdivided into three
broad sections: thoracic, abdominal and pelvic hemor rhage.
However, given the noncompressible nature of hemorrhage
in these body cavities there are certain principles that apply
to all areas, which will be discussed initially.
Considerations for All Torso Hemorrhage
Even in the most advanced prehospital services there is a
limit to the amount of resources that can be carried. This
means an extremely nite supply of blood products, when
considering the volume that is likely to be required in order
to treat exsanguinating hemorrhage, and a limited range of
possible interventions.
One of the keys for prehospital personnel managing
patients with NCTH is early recognition of the pathology.
When assessing patients for concealed, life-threatening
bleeding, an over-reliance on physiological parameters and
monitoring is potentially harmful. Patients do not always
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demonstrate the classic picture of hypotension and tachycardia, which was identied as long ago as the First World
War.47 Further study during the Second World War demonstrated that only 27% of shocked patients displayed the
classic picture of tachycardia and hypotension in the rst
hour following injury – the time when they are likely to be
seen by prehospital providers.48 A global overview of the
patient, taking into account their mechanism of injury,
features found on clinical examination such as the state of
their peripheral vasculature, their color (especially of the
gums), presence of sweating, how they feel to touch, and
nally physiological parameters, may allow more accurate
recognition of a bleeding patient.49 A simple algorithm
has been suggested with high accuracy (91%) for prehospital physicians to predict the requirement for in-hospital
blood transfusion, a surrogate of signicant blood loss. This
involves an assessment of whether the patient is bleeding,
if the systolic blood pressure is less than 90 mm Hg, and if
the patient fails to respond to initial crystalloid infusion.50
However, the rst criterion within this algorithm is clearly
subjective, as this study evaluated the performance of left
atrial appendage physicians. This group has regular exposure to bleeding trauma patients and access to a wealth of
institutional knowledge about accurate recognition of these
patients. As such, this algorithm may not work in a different
situation. This study may suggest that the judgement of an
experienced clinician may be the key in recognition of the
bleeding trauma patient.
As mentioned, denitive treatment for this type of bleeding is difcult on scene. Even temporizing measures are
challenging (see later). However, a package of care has been
described that should be applied to all bleeding patients,
which has elements that are applicable to those with NCTH.51
One of the key principles is the minimization of scene times.
However, if there is treatable pathology that can be managed
by the prehospital team, a universal “scoop and run” philosophy may lead to harm.52 Correctly managing this dilemma
again suggests the requirement for expert on-scene clinical
decision-making. Interestingly, there is a lack of literature
describing how to ensure shorter scene times, although we
would suggest that the crucial elements are rapid decisionmaking and excellent nontechnical skills.
53
Coupled to short on-scene times, careful patient handling
is important and simple changes can lead to a signicant
improvement in this area. This means minimizing forces that
could lead to disruption of clots. For example, in one study, a
change in practice from the use of longboards to using a split
orthopedic scoop stretcher for patient transfer reduced the
amount of rotational movement experienced by a patient
from 510 degrees to 170 degrees during the course of their
transfer from incident scene to the resuscitation room bed.51
The nal interventions are the administration of blood products and the use of tranexamic acid (TXA) (see later).
51
Thoracic Hemorrhage
The primary on-scene intervention that can be performed
for the management of life-threatening bleeding in the
chest is RT. As discussed previously, this is usually only performed once the patient is in TCA, although there may theoretically be a role for earlier intervention. Most survivors of
prehospital RT suffer from cardiac tamponade, usually due
to a low-velocity, penetrating injury to the right ventricle.40
It should be noted that tamponade can occur following
blunt injury, typically secondary to tearing the right atrial
appendage.54 Theoretically, this should be equally amenable
to RT, although the overall physiological insult is likely to
be greater in blunt trauma with, as in this case, injuries to
other structures in the chest, as well as concomitant injuries to other body areas more likely. In addition, the most
recent consensus statement from the Faculty of Pre-Hospital Care of the Royal College of Surgeons of Edinburgh
sees blunt injury as a contraindication to RT.55 However, the
same document acknowledges the difculty of diagnosing
tamponade in the prehospital setting, a pathology proven to
be amenable to RT, and conicts with accepted practice by
several well-respected prehospital organizations.
56
As well as the relief of tamponade, there are other procedures that can be performed to aid the management of
intrathoracic hemorrhage. In particular bleeding from the
lung can be managed by hilar clamping, lung twist, or compressing the lung with an “inco pad.”
When considering the appropriateness of prehospital RT, access to timely and expert onward care must be
considered. There is little benet in undertaking RT if the
nearest ED is several hours away. Particularly in the case
of the patient with life-threatening hemorrhage, aggressive damage control resuscitation is likely to be required
concomitantly, or at least very shortly after RT.
43
Abdominal Hemorrhage
RT with aortic control is also an option for the management
of intraabdominal hemorrhage. Again, some survivors have
been reported from the use of this procedure in-hospital.43
Prehospital laparotomy to allow four quadrant packing is
not routinely performed, and is probably not feasible. This
is due to the requirement for large blood volumes once any
tamponading effect of the abdominal wall is released, a lack
of surgical expertise, and limitations of equipment in the
prehospital environment.
Zone 1 REBOA, where the balloon is placed between the
left subclavian artery and the coeliac artery, has been suggested as a technique for the control of abdominal hemorrhage.57 This has never been performed prehospital and
therefore all data regarding its use must be extrapolated
from the in-hospital setting. Prehospital zone 1 REBOA is
feasible: access to the femoral vessels should be no more
difcult than for zone 3 REBOA. A fuller discussion of the
physiological effects of zone 1 versus zone 3 REBOA is
beyond the scope of this chapter, but further information is
available in Chapter 11.
In terms of the desirability of undertaking zone 1 REBOA,
the evidence is mixed. One Japanese case series describes
the use of REBOA as a temporizing measure, pending
angioembolization of abdominal solid viscus bleeding.
Numbers are small (seven patients) but they report an 86%
survival with no complications of REBOA.58 One patient
died as a result of head injury.58 Interestingly, however,
they also describe how they let the balloon down every
20 minutes and rapidly transfused blood products: this
would not be possible in the prehospital environment due
to the inability to carry large amounts of blood. Another
Japanese study reported worse survival in patients treated
with REBOA, although this could be due to the manner in
which REBOA was employed as a last-ditch technique.
32,59
5 • Prehospital Management of Vascular Injury 63
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Timely and accurate decision-making again seems key in
the effective use of REBOA. It must be considered in the
appropriate patient group and, when necessary, employed
as early as is feasible; as with RT, it should be seen as an
integral part of the resuscitation effort, and not something
to try once all else has failed.
44
As with junctional hemorrhage there are some novel
techniques for the management of intraabdominal hemorrhage. Once more, most of these techniques involve the
use of pressure to tamponade bleeding. There is a theoretical possibility that an externally applied tourniquet could
help to tamponade intraabdominal bleeding.32 In both
preclinical trials and in elds other than trauma, external
abdominal pressure has been shown to effectively arrest
aortic blood ow or massive obstetric hemorrhage, respec-
60,61
tively.
However, This is likely to be more applicable to
pelvic bleeding due to the most likely sources of signicant
intraabdominal bleeding being relatively proximal, especially in blunt injury.
Internal compression of abdominal hemorrhage can
be applied via gas insufation or self-expanding foam.
62,63
Porcine models of intraabdominal hemorrhage have found
reduced bleeding in both visceral and vascular models
of injury.
62,64
This has been shown to be plausible in the
prehospital environment with the use of a portable CO2
insufator.62 There are theoretical risks associated with
abdominal insufation. Amongst them are the risk of tension pneumothorax if concomitant diaphragmatic injury
is present and, in patients with head injury, raised intraabdominal pressure potentially leading to raised intracranial
pressure (ICP).65 It should be noted that in elective surgery,
abdominal insufation with CO2 in patients with diaphragmatic defects has not led to physiologically compromising
pneumothorax.
66
Intraabdominal foam is a second option for intraabdominal pressure control of hemorrhage. Once injected,
the foam expands up to 35 times, engulfs the organs, and
becomes solid, thus tamponading the bleeding.
this has proved effective in both porcine and cadaveric
models of solid viscus and vascular injury.
32,67
68–70
Again this
So far
is potentially feasible within the prehospital environment.
However, in addition to the concern about raised ICP
already outlined, there are specic concerns related to the
use of foam. First, once the foam has been deployed, the
patient requires a laparotomy to remove it. It is usual at
this point that there is some injury to the bowel requiring
repair or even resection.
68,70
Second, similar to concerns
about air entering the pleural cavity in abdominal insufation, if a diaphragmatic injury is present, there are concerns that foam could enter the pleural cavity and cause
a “foamothorax.”67 Experimental results suggest that this
may be a problem in larger diaphragmatic tears, which
are usually associated with blunt rather than penetrating injury. As such, caution may need to be exercised
when using foam for patients with blunt intraabdominal
hemorrhage.
67
The nal category of possible prehospital treatments for
intraabdominal hemorrhage proposed in the literature base
are energy-based hemostatic devices. All seem to be some
way from being in a format that could be reliably deployed
prehospital, and there are signicant challenges with their
use in the prehospital environment.
65
Pelvic Hemorrhage
Prehospital management of pelvic hemorrhage can again
be challenging. There are two key techniques. First is the
use of a pelvic circumferential compression device (PCCD).
This term encompasses both specically designed pelvic
binders and improvised devices such as bed sheets.
Although a full description of the classication of pelvic
fractures is outside the remit of this chapter, some understanding is necessary to understand the utility of these
devices. A simple explanation of pelvic fracture mechanisms is that they can occur due to anteroposterior (AP),
lateral, or vertical force, or indeed due to a mixture of these.
This underpins the Young-Burgess classication. These can
lead to different fracture patterns. The fracture most amenable to pelvic binder use is that resulting from an AP force,
which causes the pelvis to fracture in an “open-book” pattern with disruption of the symphysis pubis and sacroiliac
joint(s). Application of a pelvic binder in this situation aims
to reduce intrapelvic volume and thus tamponade bleeding, which is often of low-pressure, venous origin. On the
other hand, if the injury has been caused by a lateral force
it is easy to see that a pelvic binder may simply replicate the
initial force that caused the injury. There are also concerns
about the possibility of PCCDs causing pressure necrosis or
even peroneal nerve palsy.
72,73
Therefore, PCCDs should not
be applied thoughtlessly to all trauma patients. Box 5.4 out-
lines criteria for major trauma patients, with a mechanism
consistent with pelvic injury, who do not require PCCD
application.74 If a PCCD is used it should be seen as a treatment for bleeding and not merely a packaging device. Thus,
if they are applied, they should be applied early, if possible
prior to extrication.
74
The second prehospital technique for managing pelvic
bleeding is zone 3 REBOA. The principles of REBOA in pelvic
bleeding are identical to those in junctional hemorrhage.
MAXILLOFACIAL HEMORRHAGE
The nal area from which exsanguinating hemorrhage can
occur is the face. Successfully controlling massive maxillofacial hemorrhage requires specic equipment and expertise.
However, control is possible in the prehospital environment.
Maxillofacial hemorrhage is usually associated with signicant blunt force; for example, following a motor vehicle
collision or a fall from height.
The rst consideration when dealing with maxillofacial
hemorrhage is to secure the airway with a cuffed tube in
the trachea. The airway is almost always at risk because of
the large amounts of blood that will be within it. All PHEA
should be undertaken with the aim of maximizing the
Box 5.4 Major Trauma Patients Not Requiring
a Pelvic Binder
A pelvic binder need not be applied if all of the following criteria
are met:
1. Patient has a Glasgow Coma Score >13
2. Patient is not shocked
3. Patient does not have a distracting injury
4. No pain on clinical assessment of the pelvis
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64 SECTION 2 • Immediate Management and Diagnostic Approaches
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chance of rst-pass success. However, along with patients
with neck hematomas, this is a case where especial care and
preparation are required. It is advisable to preoxygenate the
patient in whatever position allows optimal blood drainage. This is most likely to be sitting up or in the left lateral
position. Further information about optimizing the chances
of intubation success is available in the section discussing
neck injury.
Having secured the airway, the facial skeleton must then
be realigned. This is done using three different devices. First,
nasal epistats (Fig. 5.5) should be inserted bilaterally. Do not
inate the epistats at this stage. Next, place appropriately
sized McKesson props (Fig. 5.6) and tie the chains together
to prevent them being accidentally displaced, ingested, or
inhaled. Secure a rigid cervical collar in the usual way.
At this point, the epistats can be inated, starting with the
posterior balloon.75 This aims to restore normal anatomy,
If the patient deteriorates as a result of this intervention,
the devices should be removed. It is possible to manually
replace the maxilla either as a temporizing measure prior
to the complete package of care being delivered, or if the
necessary equipment is not available.
SUMMARY
Bleeding is a signicant cause of death in trauma. Simple interventions, such as direct pressure and the use of
extremity tourniquets, can help in many cases. Application
of these simple interventions should follow a hemostatic
ladder similar to the example given in this chapter.
If bleeding is not directly compressible, the management
is more difcult and controversial. Expert clinical decisionmaking is often required in these cases. Depending on the
available skill set and geography, it may be appropriate to
treat these patients using a “scoop and run” approach.
Some on-scene interventions have been shown to work in
specic groups of patients. Innovative treatments for the
most difcult patients are being developed, but most are
some way from being ready for universal adoption.
Replacing Lost Volume
GENERAL CONCEPTS
Fig. 5.5 Nasal epistats for the management of maxillofacial hemor-
rhage. The white, 10-cc port is for inflation of the distal balloon and the
green, 30-cc port is for inflation of the proximal balloon. (With permis-
sion from Dr K Sharpe, personal photos.)
Fig. 5.6 McKesson props for the management of maxillofacial hemorrhage. The smooth surface is placed against the buccal mucosa. (With
permission from Dr K Sharpe, personal photos.)
Understanding the physiological principles behind volume
resuscitation of the trauma patient is probably the most
robust way to ensure optimized resuscitation for an individual trauma patient in front of a prehospital clinician.
There is a requirement for a nuanced approach to resuscitation that dees simple application of protocols. As such,
some time will be spent exploring the scientic rationale
behind how patients are resuscitated. There is evidence of
improved outcomes in bleeding patients treated prehospital
by expert teams.
4
The lethal triad is a concept familiar to most involved in
trauma care. The dangers of acidosis, hypothermia, and
coagulopathy have been understood for some time.76 Given
the universal acceptance of these factors as deleterious, a
sound resuscitation strategy must seek to minimize them.
Hypothermia is difcult to reverse in the prehospital environment. However, steps should be taken to minimize heat
loss, including minimizing exposure and packaging of the
patient with appropriate covering. It is worth mentioning
that this must be balanced by the requirement for access to
the patient, especially during the initial assessment of the
patient. On the other hand, the management of acidosis and
coagulopathy are more complex; both are caused by tissue
hypoperfusion. With respect to trauma patients, this hypoperfusion is predominantly secondary to bleeding. The best
way to prevent acidosis and coagulopathy is still somewhat
uncertain, and in order to understand why, it is necessary to
understand two competing theories. The rst is the paradigm
of care that states we should keep blood pressure low in
order to avoid “popping the clot”; the second is to ensure
maximum perfusion and thus prevent the undesirable
sequelae of hypoperfusion, such as acute traumatic coagulopathy (ATC; see later). Pressure and ow are linked but
are not analogous. If you consider these priorities, it is
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