Page 64 - JSOM Fall 2025

more overfills than underfills for OG (P=.59). BC, PC, and OG PC averaged significantly higher than BC (P<.0001). The data
did not significantly differ in underfills (each P>.05), at least demonstrated that the majority of novices would use BC reluc-
in part due to the modest sample size for the expert group tantly, PC willingly, and OG eagerly in a combat environment.
(n=10).
Expert Group: Use in a Combat Environment
OG (mean 2.8 [SD 0.5]) averaged significantly higher than
User Ratings and Assessments
PC (mean 1.9 [SD 0.7] P<.0001) and BC (mean 1.0 [SD 0.5]
Novice Group: Confidence P<.0001) for the expert group (Table 1). PC averaged sig-
Confidence ratings for the novice group were significantly nificantly higher than BC (P<.0001). The majority of experts
higher for OG (mean mean 4.6 [SD 0.6]) than PC (mean 4.1 would use BC reluctantly, PC willingly, and OG eagerly in a
[SD 0.8] P<.0001) and BC (mean 3.0 [SD 1.2] P<.0001). PC combat environment.
confidence ratings were significantly higher than BC (P<.001).
Qualitative Responses: User Likes and Dislikes
Expert Group: Confidence Participants were asked to detail their likes and dislikes for each
Confidence ratings for the expert group were significantly technique. BC qualitative responses were generally negative.
lower for BC (mean 3.0 [SD 1.5]) than PC (mean 4.3 [SD = 0.7] The most common positive responses from both novices and ex-
P<.04) and OG (mean 4.7 [SD 0.5] P<.02). Confidence ratings perts were that BC prevents overfills and that BC is a “set it and
for PC were somewhat lower than OG (P=.10). forget it” or “self-stop” technique. However, some responded
that they like “nothing” about BC. Dislikes included that BC is
Novice Group: Accuracy, Easy to Use, Use in the Real World difficult to visualize and therefore difficult to judge whether the
For the novice group, OG was the most common choice and bag is filled or still filling, and that the BC progressively impedes
BC was the least common choice for accuracy, ease of use, and flow rates, which leads to underfills. BC is an additional piece
use in the real world (each P<.0001) (Table 1). of equipment that may be easily misplaced, requires the user to
remember to apply the BC prior to IV access, and the BC is dif-
TABLE 1 Subjective Assessments by Group ficult to remove. Further, they report that BC makes it difficult
Method Assessment to agitate the blood within the bag to prevent clot formation.
Most accurate, easiest to use, Most Real
use in the real world accurate Easiest world PC qualitative responses were mixed. The most common pos-
Novice itive responses from both novices and experts were that PC
BC 3 0 0 was quick, easy, intuitive, made it easy to visualize blood flow,
and allowed for multiple re-checks without manipulating the
PC 28 21 14 blood bag. Common dislikes from both novices and experts
OG 69 79 86 were that PC requires a small piece of equipment that may be
Expert easily misplaced, and that PC is subjective regarding when the
BC 10 0 0 PC ends were touching without compression. Some novices
PC 30 10 10 indicated that they verified PC using the OG technique.
OG 60 90 90
Use in a combat environment Reluctantly Willingly Eagerly OG qualitative responses were generally supportive. Novices
Novice and experts liked that OG was simple, easy, and required no
additional equipment. Novices in particular liked that no
BC 87 13 0 preparation is required and that the operator can agitate the
PC 9 79 11 blood and citrate while checking blood volume. Novices and
OG 0 20 80 experts disliked that OG is subjective, which can lead to un-
Expert derfills and overfills, and requires monitoring, with frequent
BC 90 10 0 lifting of the bag. Further, OG may require practice repetitions
PC 10 60 30 to become proficient, and this landmark-based technique may
OG 0 0 100 be challenging in low-light conditions.
BC = beaded cable; OG = operator gestalt; PC = paracord.
Discussion
Expert Group: Accuracy, Easy to Use, The present study makes a unique contribution to the litera-
Use in the Real World ture by assessing 6.5" BC, 10" PC, and OG techniques in the
For the Expert group, OG was the most common choice and accuracy of achieving the correct blood bag fill volume, un-
BC was the least common choice for accuracy, easiest to use, derfills, overfills, and the subjective assessments of both nov-
and use in the real world (Table 1). The choice of OG was sig- ices and experts within the Valkyrie program. This study has
nificantly more common than for BC and PC for easiest to use important implications for preserving the life of the wounded
and for use in the real world (each P<.02). warfighter in need of safe blood transfusions in walking blood
bank (WBB) scenarios.
Novice Group: Use in a Combat Environment
Using a 3-point scale (reluctantly = 1, willingly = 2, eagerly The BC technique performed poorly in the present study. For
= 3) to rate their inclination to use each technique in a com- both novices and experts, BC had the lowest proportion of cor-
bat environment, OG (mean 2.8 [SD 0.4]) averaged signifi- rect fills and was lowest in all subjective assessments. The find-
cantly higher than PC (mean 2.0 [SD 0.5], P<.0001) and BC ing that the BC strategy led to underfills in half of the experts
(mean 1.1 [SD 0.4], P<.0001) for the novice group (Table 1). and more than half of the novices was not consistent with the

62 | JSOM Volume 25, Edition 3 / Fall 2025