Page 113 - 2022 Spring JSOM

An Ongoing Series

Hemoglobin-Based Oxygen Carrier for the Reconstitution of
Canine Freeze-Dried Plasma in an In Vitro Model of Resuscitation

Thomas H. Edwards, DVM, MS, DACVECC*; Michael A. Meledeo, PhD;
Grantham C. Peltier, MS; Alice F. Henderson; Rachel M. Hammill;
Colby S. McIntosh; James A. Bynum, PhD

ABSTRACT
Military working dogs (MWDs) are force multipliers that are restoration of effective circulating volume while minimizing the
at risk for severe trauma when employed on the battlefield. aforementioned complications from crystalloids and colloids.
2,3
When in severe hemorrhagic shock, MWDs require both oxy- However, traditional blood products have logistical challenges
gen-carrying capacity and replacement of vascular volume and to include the requirement of different cold storage conditions
coagulation factors. The objective of this study was to evaluate for different products and relatively short shelf lives. 4,5
the hemostatic capacity of canine freeze-dried plasma (cFDP)
with a Food and Drug Administration (FDA)-approved hemo- Previous studies have documented the injuries sustained by
globin-based oxygen carrier (HBOC) in an in vitro model of re- military working dogs (MWDs) on the battlefield, which are
suscitation. Whole blood (WB) was collected from 10 MWDs, similar to those sustained by their human counterparts. Rec-
6–8
and these samples were diluted by 10%, 25%, or 40% with ommendations have been made that severely injured MWDs
either cFDP (reconstituted with water), HBOC, cFDP (reconsti- (and canines in general) would likely benefit from similar he-
tuted with HBOC), or an equal volume of a 1:1 ratio of cFDP mostatic resuscitation protocols that are recommended for
(reconstituted with water) and HBOC. Hemostatic parameters severely injured people in hemorrhagic shock. 9–11 Though
were minimally changed based on evaluation of prothrombin veterinary medical and surgical resources are well established
time, activated partial thromboplastin time, fibrinogen and for MWDs in mature theaters, resources are lacking in highly
thromboelastography at the 10% and 25% dilutions, and pa- tactical and far-forward environments. These austere environ-
rameters consistent with a hypocoagulability were seen at di- ments complicate the logistics of getting canine specific blood
lutions of 40%. Based on the results of this study, additional products to injured MWDs. This has led to interest in find-
12
research is warranted to determine if cFDP reconstituted with ing blood products or blood substitutes that do not pose sig-
HBOC is a viable resuscitation product in canine trauma. nificant logistical hurdles. The Department of Defense (DoD)
has sponsored two companies to develop cFDP, and a recent
Keywords: canine; hemoglobin-based oxygen carrier; freeze- study showed that one of the products, when reconstituted
dried plasma; oxyglobin; thromboelastography; dogs with sterile water per manufacturer’s specifications, performs
13
similarly to canine fresh frozen plasma. An HBOC that is
FDA approved for use in dogs (HB-200-Oxyglobin) is no lon-
ger commercially available but may become available in the
Introduction
future. This product has a long track record of successfully
Fluid resuscitation is a cornerstone of hemorrhagic shock man- treating anemic dogs with few significant side effects. 14–16 Ox-
agement in both humans and animals. The use of crystalloid yglobin has the advantage of long shelf life (labeled for 36
and colloid solutions to restore effective circulating volume months), is stable at room temperature, and can be infused
has been the standard of care for years. However, crystalloids without the concern for transfusion mismatch while delivering
and synthetic colloid-based resuscitation strategies can cause oxygen-carrying capacity to the recipient. 17
a hypocoagulability by way of a significant hemodilution of
red blood cells, platelets, and coagulation factors as well as The combination of cFDP and HBOC is an extremely attrac-
impaired platelet function and fibrin formation. Alternatively, tive option for resuscitating severely injured canines, particu-
1
resuscitation with blood products to include whole blood, larly in austere environments. This combination of products
packed red blood cells, platelet products, and plasma allow for potentially allows for both oxygen carrying capacity as well
*Correspondence to ugadvm2006@hotmail.com
LTC (Ret) Thomas H. Edwards, Dr Michael A. Meledeo, Grantham C. Peltier, SPC Alice F. Henderson, SSG Rachel M. Hammill, Colby S.
McIntosh, and Dr James Bynum are all affiliated with the US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX. LTC (Ret)
Edwards is also an adjunct professor at Lincoln Memorial University College of Veterinary Medicine and a critical care specialist at BluePearl
Veterinary Specialists in San Antonio, TX.

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