Page 114 - 2022 Spring JSOM

as the provision of clotting factors and restoration of effective FIGURE 1 Study design for dilutions of canine WB with different
circulating volume in a shelf stable product. Furthermore, if products. WB was obtained from 10 MWD and diluted with either
cFDP could be reconstituted with HBOC rather than sterile cFDP reconstituted with sterile water, an HBOC, cFDP reconstituted
with HBOC, or a 1:1 mixture of HBOC and cFDP reconstituted
water, the resultant product would provide an overall reduc- with water to give an equivalent dilution. Dilutions were performed
tion to the volume infused, allowing the replacement of an at 10%, 25%, and 40%.
equal amount of coagulation factors and oxygen-carrying ca-
pacity in a more concentrated form and thus a shorter time to
deliver both products. Additionally, if the hemostatic capacity
and oxygen-carrying properties are not significantly adversely
affected by reconstituting cFDP with HBOC rather than sterile
water, this combination would potentially eliminate the need
for medics and other dismounted providers to carry sterile wa-
ter for cFDP reconstitution. This study proposes to examine
the feasibility of reconstituting cFDP with HBOC rather than
sterile water and evaluating hemostatic parameters at different
volumes in an in vitro model of resuscitation.

Similar work has been done with human blood, a different
18
HBOC (HBOC-201) and human FDP. This work showed concentration (STA R Max, Stago Corporation https://www
that reconstitution of human FDP with an HBOC similar to .stago-us.com/).
oxyglobin had only a modest impact on coagulation measures
and reduced dilutional impact in a resuscitation model. The
success with these human products gives credence to the no- Statistical Methods
tion that similar success can be expected with canine products Descriptive statistics were reported as mean ± standard de-
using an FDA-approved HBOC and an cFDP product that is viation. One-way ANOVA tests were used to determine the
expected to be FDA cleared in the near future. intergroup differences between samples with Tukey’s test for
multiple comparisons. Data were analyzed using commer-
Materials and Methods cial statistical software (Graphpad Prism 8.1.2, https://www
.graphpad.com/). Significance was set at p < .05.
This experiment was approved by the DoD Military Working
Dog Veterinary Services’ (DODMWDVS) Institutional Animal
Care and Use Committee (protocol number 2020–02). Whole Results
blood (WB) was collected from 10 MWDs stationed at Joint Sample Population
Base San Antonio-Lackland into three 4.5mL blood collection Ten healthy MWDs provided blood for this study. Six dogs
tubes containing citrate anticoagulant (3.2%, Becton Dickin- were Belgian Malinois, three were German Shorthaired Point-
son, https://www.bd.com/en-us). Each MWD was considered ers, and one was a German Shepherd. Six were intact males,
healthy based on history, physical exam, and results of the three were intact females, and one was a spayed female. The
most recent complete blood count (CBC) and biochemical mean age of the MWDs in this study was 1.4 (± 0.7) years.
analysis as performed at the DODMWDVS.
PT/aPTT/Fibrinogen
Blood was maintained at room temperature and immediately For the PT measurement, there were no statistically significant
transported from the DoD Military Working Dog Center on changes from baseline (undiluted WB) at the 10% dilution, but
Lackland Air Force Base to the US Army Institute of Surgi- significant changes were seen with all combinations of prod-
cal Research for analysis, where it was analyzed on the day ucts at the 25% and 40% dilutions (Figure 2A). Additionally,
of collection. WB was placed into test tubes and diluted with when WB was diluted 40% with HBOC, the PT was signifi-
one of four products: cFDP (StablePlas, BodeVet, https://www cantly prolonged compared to the 40% dilution with cFDP.
.bodevet.com/) reconstituted with water, HBOC (oxyglobin There was no significant change in aPTT seen at any dilution
HB–200, HbO2 Therapeutics, https://www.hbo2therapeutics. with any of the products (Figure 2B). On the other hand, there
com/), cFDP reconstituted with an equal volume of HBOC, or was a statistically significant decrease in fibrinogen when WB
an equal volume of cFDP and HBOC at a 1:1 ratio (Figure 1). was diluted at 10% with HBOC but no change with a 10%
cFDP products were prepared by splitting the dried powder dilution of any other product mixtures (Figure 2C). At 25%
into two equal aliquots by mass (NewClassic SG (ML802E), dilution, all of the products created significant drops in fibrin-
Mettler Toledo, https://www.mt.com//) and reconstituting in ogen compared to WB except for cFDP-only. Additionally, the
125mL of either sterile water or HBOC (half of the original dilution with 25% HBOC showed a very significant decrease
manufacturer-recommended reconstitution volume, maintain- in fibrinogen compared with not only WB but also with the
ing manufacturer intended concentrations). The investigators 25% dilution with cFDP. There was a significant decrease in
diluted the WB samples at 10%, 25%, or 40% to mimic clini- fibrinogen for all products at the 40% dilution, as well as a
cally relevant resuscitation volumes. significant decrease in fibrinogen in all mixtures containing
HBOC versus the cFDP-only 40% dilution.
The WB samples were analyzed using kaolin-activated thrombo-
elastography (TEG 5000, Haemonetics, https://teg.haemonetics Thromboelastography
.com/). Remaining sample was centrifuged for plasma at 2000g There was no change from baseline (undiluted WB) in reac-
for 20 minutes and analyzed for prothrombin time (PT), ac- tion time (R) with any of the products at any dilutions (Figure
tivated partial thromboplastin time (aPTT), and fibrinogen 3A). The only change from baseline with regard to the kinetics

112 | JSOM Volume 22, Edition 1 / Sping 2022