Page 130 - JSOM Winter 2021

hemorrhagic shock needs to be reevaluated and the military Several studies in recent Overseas Contingency Operations
focus on prehospital blood products as the resuscitation fluid have demonstrated improved survival when whole blood was
of choice for combat injuries requiring resuscitation needs to used to resuscitate casualties in hemorrhagic shock. 2,30,31 The
be strengthened. 33 2014 TCCC reexamination of fluid resuscitation options for
casualties in hemorrhagic shock found that whole blood was
The following is a review of fluid resuscitation options in hem- 1
orrhagic shock with recent literature updates included. the optimal fluid for that purpose. This demonstrated survival
benefit is much enhanced when the casualties being treated are
critically injured and when whole blood administration begins
Discussion
as soon as possible after the onset of shock.
(1) Is there a specific blood product that is preferred
over others for resuscitation of casualties in hemorrhagic Whole Blood – Modern Use on the Battlefield
shock in TCCC? Whole blood is a generic term for unfractionated blood col-
lected in a single bag that includes an anticoagulant solution
Whole Blood – A Brief History of Combat Use to sustain red blood cell integrity. To understand the risks and
The use of whole blood as the best option for resuscitating
wartime casualties in hemorrhagic shock is a lesson that has benefits of whole blood transfusions, it is important to dif-
been learned by the US military three separate times in three ferentiate the various methods of collection, storage, and use.
separate conflicts. Dr. Walter Cannon was a strong advocate There are four primary options for whole blood on the mod-
5
for using whole blood to treat casualties in hemorrhagic shock ern battlefield.
in World War I. During the period after World War I, how- • CS-LTOWB is collected by blood banks, screened for
ever, physicians and physiologists began to consider shock as transfusion-transmittable infections, and tested to en-
being primarily due to loss of plasma volume from the intra- sure low titers of anti-A and anti-B antibodies. It is
vascular space, suggesting that plasma might be just as good thus FDA compliant and is a universal donor option
as whole blood. It was also logistically easier to ship units of for blood transfusions. The ASBPO has increased the
dried plasma to frontline troops. production and delivery of this type of stored blood to
combat theaters. It does, however, require storage in the
These two factors combined to make plasma the preferred recommended cold conditions, which imposes logistical
fluid to use for resuscitation from hemorrhagic shock at the issues for combat units. Both safety and Department of
start of World War II. As a result, early in World War II, the Defense policy require that FDA-compliant blood prod-
US Army Surgeon General declined to supply whole blood to ucts be used for combat casualties unless such products
combat units. During the course of the war, however, surgeons are not available or are deemed to be not clinically ef-
like Colonel Edward Churchill noted that American casualties fective by the providing physician. The increasing
35
who were being treated with plasma were faring less well than availability of portable blood coolers for use on the
34
British casualties who were being treated with whole blood. battlefield now often makes this option feasible even in
Additionally, the use of pooled plasma products entailed an far-forward environments, especially when the military
increased risk of hepatitis.
operation being supported entails the use of tactical air-
Colonel Churchill subsequently requested that whole blood be craft or vehicles. 5
supplied to US Army combat forces. Churchill’s request was • Fresh LTOWB is collected from donor pools of individ-
denied. This story subsequently found its way to the New York uals who have been prescreened to ensure that they were
Times. The Times ran a story in August of 1943 and the US free from transfusion-transmittable infections and that
military restarted its whole blood program shortly thereafter. their Type O blood contains low titers of anti-A and
In Okinawa alone, over 40,000 pints of whole blood were re- anti-B antibodies. These prescreened donors are thus
portedly used for casualties. 34 able to act as relatively low-risk sources of universal
donor whole blood when needed in far-forward envi-
Despite whole blood having been “re-discovered” by the US ronments. The 75 Ranger Regiment has demonstrated
th
military as the preferred resuscitation fluid for casualties in the feasibility of establishing such a program in front-
shock in World War II, this important aspect of care was again line combat units with their Ranger Type O Low Titer
lost in the mid-1970s, when transfusion practice moved from (ROLO) effort. Fresh whole blood can be stored at
11
the use of whole blood to using individual blood component room temperature for 24 hours, and some data suggests
(RBCs, plasma, or platelet) therapy after blood fractionation this timeframe may be safely extended to 72 hours. It
36
became technologically feasible. This change occurred despite can also be refrigerated within 8 hours at which point it
the lack of evidence for the benefit of this strategy when used becomes known as stored whole blood.
for patients in hemorrhagic shock. 1
• Fresh group O unititered whole blood is also collected
Another development in fluid resuscitation that occurred from donor pools in combat settings when neither of the
during the Vietnam era was the thought that adequate fluid first two options for whole blood are available. The risk
resuscitation could be accomplished with crystalloid solutions of transfusion reactions from type O donors with un-
if the volume provided was approximately three times the vol- known levels of anti-A and anti-B antibodies has been
ume of estimated blood lost in order to account for the fact shown to be low, but the risk of transfusion-transmitta-
that only about one-third of the crystalloid solution infused re- ble infections remains. This option for obtaining whole
mained in the intravascular space. This led to the emergence of blood when FDA-compliant whole blood is not available
fluid overload syndromes during the Vietnam conflict. Excess has been used widely in combat support hospitals. 31
fluid in the pulmonary system was dubbed “Da Nang Lung” • Type-specific fresh whole blood provides for ABO-
and was the best-known entity, but fluid overload in the abdo- identical transfusions but entails the risk of a fatal he-
men and the brain can be deadly as well. molytic reaction in the event of an ABO-mismatch due

128 | JSOM Volume 21, Edition 4 / Winter 2021