Page 61 - Journal of Special Operations Medicine - Winter 2014

Table 3 Comparison of Sensitivity and Specificity of the 120/min, increased the sensitivity to 76% but produced
Current US Guideline Versus Modified Anatomical and a slight drop in specificity to 86%.
Physiological Indicators Determined by the Authors
Sensitivity, % Specificity, % The findings of our study were derived from single sets
Indicators
(95% CI) (95% CI) of retrospective data. While the need to develop specific
Current DUSTOFF prehospital clinical data collection tools has become the
Guideline focus of military prehospital clinicians for the coming
13
Double above-knee 63.04 89.07 years, the data analysis was limited to the physiologi-
amputation + SBP (47.55–76.79) (85.73–91.86) cal parameters completed by the prehospital providers
<90mmHg + pulse and stored in JTTR. Although this study offers external
>120/min validation of the current DUSTOFF model, additional
(Shock Index ≥1.3) analysis of alternative physiological signs in larger data
Author’s Suggestion 1 sets is ongoing to determine the most predictive values
Single above-ankle for use when identifying casualties who would benefit
amputation + SBP 67.39 89.07 from early transfusion of blood products in the prehos-
<90mmHg + pulse (51.98–80.47) (85.73–91.86) pital, remote, or austere military trauma environment.
>120/min
(Shock Index ≥1.3) Furthermore, patient vital sign monitoring is a dynamic
Authors’ Suggestion 2 process, and as such it should be possible to develop a
predictive tool to identify infliction points where discrete
Leg above-ankle changes in physiological parameters, rather than single-
amputation + SBP 76.09 85.81
<100mmHg + pulse (61.23–87.41) (82.15–88.97) value markers, would indicate the need to start blood
>120/min products in a previously stable casualty. It is hoped
(Shock Index ≥1.2) that a suitably validated simple scoring system will al-
low military medics operating remotely to determine
whether they should administer reconstituted blood
of the need for massive blood transfusion. In addition, products to seriously injured military personnel and, if
the presence of a heart rate greater than 120/min has an so, when to do it. Further studies are under way to de-
odds ratio of 8.4, while an SBP of less than 90mmHg termine the optimum time for permissive hypotension in
is also highly predictive with an odds ratio of 12.6. Us- battlefield trauma and whether, in future conflicts, there
ing statistical analysis, we were able to ascertain that is a metabolic consequence associated with delaying the
the current DUSTOFF SME-derived guidelines offer administration of blood products until more traditional
a sensitivity of 63.04% and a specificity of 89.07%. physiological markers have been reached or until the ca-
This study effectively states that, if a medic were to use sualty reaches a medical facility.
the DUSTOFF guidelines to determine whether to give
blood products in a remote or forward setting, he would Disclosures
be able to do so with a high degree of accuracy. In par-
ticular, a rule-out prediction using this tool would be The authors have nothing to disclose.
extremely accurate and would ensure preservation of
limited resources. References
1. Hodgetts TJ, Mahoney PF, et al. ABC to C.ABC: redefin-
We have found that further analysis of the anatomi- ing the military trauma paradigm. Emerg Med J. 2006;23:
cal and physiological indicators offers some interest- 745–746.
ing findings. By adjusting the indicators to include a 2. Borgman MA, Spinella PC, Perkins JG, et al. The ratio of
single above-ankle amputation with an SBP less than blood products transfused affects mortality in patients re-
90mmHg and pulse greater than 120/min, we were able ceiving massive transfusions at a combat support hospital.
to increase the specificity to 67.39% while maintain- J Trauma. 20907;63:805–813.
ing sensitivity of 89.07%. In a young and fit military 3. Lockey DJ, Weaver AE, Davies GE. Practical translation
population, we were surprised by the change in sen- of hemorrhage control techniques to the civilian trauma
sitivity associated with an SBP increase of 10mmHg scene. Transfusion. 2013;53:17S–22S.
(from 90 to 100mmHg). These findings are consistent 4. Bodnar D, Rashford S, Hurn C, et al. Characteristics and
outcomes of patients administered blood in the prehospi-
with Eastridge et al., who suggested that an SBP of tal environment by a road based trauma response team.
10
100mmHg would be a more reliable indicator of hypo- Emerg Med J. 2013. http://www.ncbi.nlm.nih.gov/pubmed
tension in a military trauma patient. In our data set, a /23645008.
single amputation above the ankle, in combination with 5. Larson CR, White CE, et al. Association of shock, coagu-
an SBP of less than 100mmHg and a pulse greater than lopathy, and initial vital signs with massive transfusion in

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