Hemostatics in tactical medicine

Hemostasis and how to stop bleeding

Before considering the ways and means of stopping bleeding, it is necessary to stop at the mechanism of their occurrence. The blood moves in the body through the vessels, this constant movement provides the heart. If the blood is out of the vessels and heart, it means that the integrity of the blood supply system has been disrupted – the bleeding began.

Hemostasis is a complex of physiological processes in the body that stop blood loss when vessels are damaged and keep the blood in a fluid state. It doesn’t matter what caused the bleeding: internal cause and external injury. The body reacts to the bleeding in all cases equally. As soon as the vessel wall is damaged, the body starts an emergency process to prevent blood loss. This is a complex mechanism involving the coordinated activation of different plasma proteins, platelets, cells and blood clotting factors that can activate each other when starting a coagulation cascade – the process of blood clotting.

The process of stopping bleeding in the body

If we look at the range of measures taken by an organism to stop bleeding, three main processes can be distinguished.

The first process is the narrowing of a damaged vessel. The walls of the muscle vessels are reduced to reduce the volume of blood flowing, and thus reduce the amount of blood loss.

The third process — in the blood, proteins are activated, which are called coagulation factors, and around the clots of platelets, strong fibrin-protein threads begin to form, which fasten the thrombocytic fibrillar plug with a fibrin net, forming a stable and constant tap. This occurs throughout the coagulation cascade involving blood plasma proteins, blood clotting factors, calcium ions and platelets. Cascade coagulation is a complex biochemical process, its result is the formation of a secondary hemostatic stopper that reliably closes the vessel wall damage.

Третий процесс — в составе крови активируются белки, которые называются факторами свертываемости крови, и вокруг пробки из тромбоцитов начинают образовываться прочные нити белка-фибрина, скрепляющие тромбоцитарную пробку фибриновой сеткой, образуя стабильную и постоянную пробку. Это происходит на протяжении всего каскада коагуляции с участием белков плазмы крови, факторов свертывания крови, ионов кальция и тромбоцитов. Каскад коагуляции — сложный биохимический процесс, его результат — образование вторичной гемостатической пробки, надежно закрывающей повреждение стенки сосуда.

Thus, as a result of the action of three processes, a clot is produced that does not allow the bleeding to continue until the vessel wall is restored.

The complex of processes is reproduced by the body regardless of the causes of damage to the vessel, as well as for vessels of any size, both small capillaries and large arteries. But if small vessels are usually enough to stop the bleeding of independent actions of the body, then with significant damage affecting large vessels, there is a risk that the person will lose a dangerous amount of blood.

Stop bleeding options

In the case of severe bleeding, deliberate measures are needed to stop blood loss:

1. direct pressure on the wound with a pressing bandage
2. Application of a girdle or tourniquet on the limb
3. wound tamponade with or without hemostatic

These options help the body in its natural mechanism of stopping bleeding. The direct pressure and compressive bandage narrows the opening of the vessel, reducing blood loss and helping to concentrate platelets and clotting factors at the point of rupture. The application of a coil or tourniquet physically stops the blood flow in the damaged vessel, preventing blood from dripping to the rupture and flowing into it. Tamponade with a regular bandage also helps to concentrate the necessary blood components in the right place and promotes rapid and effective formation of clot-clots.

Effect of local hemostatic agents

All local hemostatic agents used in tactical medicine act by enhancing one or more of the processes listed. That is, they help the body more quickly and effectively implement the natural mechanism of stopping bleeding.

Types of hemostatic

Hemostatics, or hemo coagulants, antihemorrhagic, blood-twisting and blood-retaining agents are names of a fairly broad group of substances that promote hemostasis, that is, stop bleeding. In medicine, this is a large group that includes both systemic hemostatics acting on the whole body and local hemostatics – medical devices for rapid bleeding stop directly at the site of application.

In the field of tactical medicine, we usually refer to a second group: medical products that combine forms (bandages, granules, applicator, sponge) and active agents for a successful result – stopping bleeding (zeolite, smectin, chitosan, kaolin or more rarely occurring smectin, thrombin-fibrinogen salmon).

Hemostatics can work in three ways:

1. Absorption of water from the blood and concentration of blood components at the bleeding site: materials with this ability are called factor concentrators.
2. Activation of the blood clot cascade: materials with this ability are called procoagulants.
3. Providing a physical barrier for blood flow through «gluing» of cellular components of the blood: materials with such ability are called mucoadhesives.

However, all the active substances used to produce hemostatic have one result: upon contact with blood, a chain of biochemical reactions is triggered, leading to the rapid and powerful formation of a clot. Formation of the clot in close proximity to the damaged vessel closes the bleeding and stops blood loss.