Using Topical Hemostatic Agents
This is an extended version of the article "The Use of Topical Hemostatic Agents in Athletic Training," published in the January NATA News. The article is part two of a two-part series. Part one of the series, published in the October 2016 NATA News, reviewed the concepts of hemorrhaging, shock and controlling bleeding as they relate to athletic training and prehospital emergency care.1 Part one focused on the use of tourniquets in the prehospital setting. Part two of the series will review hemostasis as it relates to the clotting mechanism and provide athletic trainers with evidence regarding the use of topical hemostatic agents in the athletic training setting.To get more news about Bleeding Control Products, you can visit rusunmedical.com official website.
HEMOSTASIS
The body’s physiologic response (hemostasis) to blood loss from trauma involves a complex three-phase process. Coordinated activation of platelets and plasma clotting factors needed to form a platelet-fibrin plug depends on the primary (formation of soft platelet plug) and secondary (stabilization and cross linkage) hemostatic phases. Of central importance in both hemostasic phases is the activation of the clotting cascade, which is broken down into two basic pathways: the intrinsic (activated by collagen, exposed when a blood vessel is damaged) and the extrinsic (activated by tissue damage and the release of tissue factors).
The clotting cascade includes a series of dependent reactions following trauma involving plasma proteins, calcium ions and blood platelets that lead to the conversion of fibrinogen-to-fibrin and an eventual soft platelet plug.2 During the initial phase, the muscular wall of a blood vessel contracts to reduce blood flow while creating a turbulent flow of blood. This turbulent flow initiates the second phase of response by attracting platelets that adhere in the presence of collagen to the vessel’s lining, surrounding tissue and each other; further reducing blood flow through the vessel. While the initial clot formed in the vessels greatly decreases blood loss, it is extremely unstable. The third phase of coagulation strengthens the clot through the incorporation of fibrin and red blood cells, resulting in clot expansion and strength.
When bleeding is uncontrollable, numerous topical hemostatic agents are available to affect the biological mechanism of action of the clotting cascade through contact activation and promotion of platelet aggregation.
During trauma situations when massive external bleeding can’t be controlled by direct pressure and/or with the use of a tourniquet (ie, hemorrhaging occurring in sites not amenable to tourniquet placement such as the abdomen, groin or chest), the application of topical hemostatic agents are warranted.3-8 Topical hemostatic agents are commonly used to control severe bleeding, especially in military and, now, civilian prehospital care.4,7 State emergency medical systems (EMS) are adding various topical hemostatic agents to ambulance supply lists.8
These antihemorrhagic substances produce hemostasis when placed in bleeding wounds by adhering to damaged tissues and sealing the injured blood vessel(s) and/or by accelerating and strengthening the clotting cascade.5 The desired characteristics of topical hemostatic agents are presented in Table 1, but currently no “ideal” topical hemostatic agent is being marketed.9,10
Several types of topical hemostatic agents have been developed and marketed for civilian prehospital use. Placed into three classes by mechanism of action and into two forms of delivery hemostatic products lack generic alternatives and vary in delivery method even among the same classes of product, so one company’s product can vary greatly from another(s).4,10 Commercially available products have undergone multiple stages of development and must be approved by the U.S. Food and Drug Administration before becoming available. Due to continued research and development (ie., military setting), there are currently three generations of agents commercial available.8 Table 2 reviews different topical hemostatic agents.
Hemostatic agents come in two forms: granular powder and embedded/impregnated dressings. These agents use two mechanisms to produce hemostasis: physically adhering to damaged tissues and sealing injured vessels to prevent further blood loss, and accelerating and strengthening the blood clotting present in the wound by incorporating into the developing clot and producing hemostasis. The second mechanism is achieved by two related reactions: rapid absorption of water from blood in the wound, which concentrates all clotting elements on the injured tissues, and chemical reaction(s) activating the intrinsic coagulation pathway and platelets to promote clot formation. These products depend on the intact coagulation function of patients. It should be noted that the majority of hemostatic agents, including those embedded in dressings, facilitate hemostasis through the second mechanism.
The three classes of action for topical hemostatic agents include factor concentrators, mucoadhesive agents and procoagulants. Factor concentrators rapidly absorb water content of blood and concentrate the cellular and protein components of the blood; this promotes clot formation.4 TraumaDEX is example of this type of hemostatic agent. It uses microporous polysaccharide hemospheres from potato starch to promote hemostasis by a gelling action to concentrate natural clotting components.10 This product doesn’t produce an exothermic reaction when used like the original QuikClot product did. While TraumaDEX is considered safe and easy to use, it has not been utilized by U.S. military forces because the product appears more effective with minor to moderate wounds, not the severe wounds seen in combat.10 This product may have more uses in civilian settings.