The leading cause of death from trauma in a military combat setting¹ and the second leading cause in civilian settings is hypovolemic shock secondary to hemorrhage².
A medical caregiver's primary life-saving efforts in the pre-hospital field conditions are focused on hemorrhage control.
Gauze has long been used to treat direct pressure compression in areas in which a tourniquet is not practical, such as groin or armpit injuries.
The treatment method was later improved to include various hemostatic agents derived from various materials and sources. These agents' function was to encourage and speed up clot creation in the injury area to assist in more efficient hemorrhage control.
While the general concept of hemostatic gauze has existed since the 1970s, the leading components generally accepted today are Kaolin and Chitosan³.
Kaolin
Kaolin is a clay-based substance that promotes factor XII in the naturally occurring coagulation cascade within our bodies. While this substance is the more "natural" option – it is still dependent on the victim's natural ability to create clots and a functioning coagulation system. That being said, studies have been performed on patients using anticoagulants – demonstrating efficacy for these populations as well⁴.
A common brand that uses Kaolin as its hemostatic agent includes Combat Gauze Quickclot.
Chitosan
Chitosan is a shellfish-based product that essentially acts as a sticky mucous adhesive and forms an artificial plug for bleeding damaged tissue⁵. This would be an attractive agent for victims with a dysfunctional coagulation cascade or patients who use anticoagulation agents.
Brands that use Kaolin as their hemostatic agent include CELOX.
Q: If a patient has a known allergy to shellfish – can they still be treated with Chitosan?
A: There have been no documented cases of shellfish allergic reactions to chitosan and the condition is not considered a contra-indication for use, however the various manufacturers advise caution when using with patients with a known allergy⁶.
So which is the superior option? Kaolin or Chitosan?
Comparative studies are inconclusive as to which agent exhibits definitive superior efficacy⁷.
While both substances are approved by the TCCC guidelines⁸ (Tactical Combat Casualty Care) guidelines, Kaolin is generally accepted as the agent of choice and more widely used substance for the US armed forces for young, healthy soldiers. However, Chitosan is still approved in the US military and can be found among the various branches of military in the field. Currently, the hemostatic gauze of choice by the IDF is the Kaolin-based gauze as well.
There is a case to be made for Chitosan in a civilian setting, given the higher probability of patients who are using anticoagulants – however, as mentioned above – both agents are viable choices.
Author:
Dr. Shalom Reich, MD
Emergency Medicine Specialist & Combat Medical Physician with extensive experience in pre-hospital and combat scenarios
REFERENCES:
1- "Died of Wounds on the Battlefield: Causation and Implications for Improving Combat Casualty Care" (2011)
Eastridge, Brian J. MD; Hardin, Mark MD; Cantrell, Joyce MD; Oetjen-Gerdes, Lynne MS; Zubko, Tamara; Mallak, Craig MD; Wade, Charles E. PhD; Simmons, John MD; Mace, James MD; Mabry, Robert MD; Bolenbaucher, Rose MD; Blackbourne, Lorne H. MD
2- "Bleeding Control Using Hemostatic Dressings: Lessons Learned" (2017)
Brad L. Bennett, PhD, EMT-P, FAWM
3- "Hemostatic agents for prehospital hemorrhage control: a narrative review" (2020)
Henry T. Peng
4- "In vitro effects of a kaolin-coated hemostatic dressing on anticoagulated blood" (2018)
Cripps, Michael W. MD, MSCS; Cornelius, Canon C.; Nakonezny, Paul A. PhD; Vazquez, Natalia; Wey, Jocelyn C.; Gales, Peter E.
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by Yi-Wen Wang, Chuan-Chieh Liu, Juin-Hong Cherng, Chien-Seng Lin, Shu-Jen Chang, Zhi-Jie Hong, Cheng-Che Liu, Yaw-Kwan Chiu, Sheng-Der Hsu, Hung Chang
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Kirk H. Waibel, MC USA, Brian Haney, MC USA, Merrideth Moore, USAF MC, Bonnie Whisman, MS, Robert Gomez, BS
7- Comparison of Celox-A, ChitoFlex, WoundStat, and Combat Gauze Hemostatic Agents Versus Standard Gauze Dressing in Control of Hemorrhage in a Swine Model of Penetrating Trauma
Lanny F. Littlejohn MD, John J. Devlin MD, Sara S. Kircher, Robert Lueken MD, Michael R. Melia MD, Andrew S. Johnson MD
8- "Two Decades of Saving Lives on the Battlefield: Tactical Combat Casualty Care Turns 20" (2017)
Frank K. Butler, MD, FAAO, FUHM