Page 37 - Journal of Special Operations Medicine - Spring 2014

brachii muscle. Over the past decade of seeing hundreds prepared as part of their official duties and, as such,
of users in care or training, we have never detected a there is no copyright to be transferred.
user who preferred to pronate in turning the windlass.
Now that we detected one such user, we relabeled the Disclosures
turn directions as clockwise and counterclockwise (pre- This project was funded with internal USAISR funds
viously we used right and left in assuming all supinated), and the Defense Health Program (Proposal 201105:
and we suspect that we may have overlooked infrequent Operational system management and postmarket sur-
or rare pronators. We also alerted trainers and tourni- veillance of hemorrhage control devices used in medical
quet investigators that some users may pronate.
care of U.S. Servicepersons in the current war).
The strength of the present report is its experimental The authors have nothing to disclose.
design, which allowed a powerful statistical analysis of
several variables of interest. By reporting on a tourni-
quet experiment, the present report shows investigators References
a scientific approach to studying emergency healthcare 1. Kragh JF Jr, Walters TJ, Baer DG, Fox CJ, Wade CE, Sa-
in a way that is understandable and practical. Such an linas J, et al. Practical use of emergency tourniquets to
approach is suitable for further experiments in address- stop bleeding in major limb trauma. J Trauma. 2008;64(2
ing the questions of tourniquet users whether used by Suppl):S38–S49; discussion S49–S50.
the present investigators or any others so interested. 2. Kragh JF Jr, Walters TJ, Baer DG, Fox CJ, Wade CE, Sali-
nas J, et al. Survival with emergency tourniquet use to stop
bleeding in major limb trauma. Ann Surg. 2009;249(1):
Study Limitations and Future Directions 1–7.
3. Kragh JF Jr, Littrel ML, Jones JA, Walters TJ, Baer DG,
Limitations of the present report are several. An ex- Wade CE, et al. Battle casualty survival with emergency
periment on a manikin does not model clinical care tourniquet use to stop limb bleeding. J Emerg Med. 2011;
complexity in its entirety but focuses on the controlled 41(6):590–597.
variables of interest. The experiment is mechanical in 4. Kragh JF Jr, O’Neill ML, Walters TJ, Jones JA, Baer DG,
nature and does not allow easy study of human factors Gershman LK, et al. Minor morbidity with emergency
like user knowledge, experience, or skill. tourniquet use to stop bleeding in severe limb trauma: re-
search, history, and reconciling advocates and abolitionists.
Mil Med. 2011;176(7):817–823.
Future directions for research are several. A clinical ques- 5. Rolen R, Costello M, Calkins M, Bentley T. Development
tion remaining unanswered is whether a medial wound of a tourniquet testing fixture for evaluation of far forward
is best treated with lateral or medial tourniquet place- battlefield tourniquet devices. Washington, DC: Depart-
ment as it is not known whether one tourniquet position ment of Mechanical Engineering, Oregon State University,
applies more pressure on an injury on the opposite side Corvallis, OR and Division of Surgery, Walter Reed Army
of the extremity. To date, evidence in mechanical mod- Institute of Research; 2002.
els indicates that circumferential extremity tourniquets 6. McKeague AL, Cox DD. Joint Operational Evaluation of
of conventional designs are generally symmetric in their Field Tourniquets: Final Report Phase 1, Combat Casualty
medial-lateral pressure distribution. 5,6 Care Research Department, Naval Medical Research Unit
San Antonio, 2013.
In summary, the present study reports a manikin ex-
periment that found that medial, lateral, anterior, and
posterior positioning of a windlass-and strap emergency COL (Ret) Kragh, MC, USA, is a tourniquet researcher at
tourniquet had 100% effectiveness irrespective of posi- the U.S. Army Institute of Surgical Research (USAISR) and
tion, but that several associations detected, such as with an assistant professor at the Uniformed Services University of
blood loss volumes by position, are opportunities for fur- the Health Sciences, F. Edward Hébert School of Medicine,
Bethesda, MD. He is an orthopedic surgeon who previously
ther study in order to develop best tourniquet practices.
served at 3d Ranger Battalion from 1990 to 1993. E-mail:
john.f.kragh.civ@mail.mil.
Acknowledgments
Mr. Wallum is a biological science technician at the USAISR.
Otilia Sánchez aided in manuscript preparation.
Dr. Aden is a statistician at USAISR.
Disclaimers Dr. Dubick is currently a supervisory research pharmacolo-
The opinions or assertions contained herein are the pri- gist and the task area manager of Damage Control Resuscita-
vate views of the authors and are not to be construed tion at the USAISR.
as official or reflecting the views of the Department Dr. Baer is director of research at USAISR.
of Defense or United States Government. The authors
are employees of the U.S. Government. This work was

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