Hemostatic tourniquet

The role of the tourniquet in anti-shock measures

Tourniquet application is part of a strictly regulated set of anti-shock measures. The main rule of this complex is that actions to maintain vital functions must be started as early as possible, without waiting for the appearance of obvious life-threatening disorders.

At the pre-hospital stage, medical care implies only temporary cessation of external bleeding. Definitive hemostasis (wound revision, vascular reconstruction, ligation in continuity, or ligature placement) is performed exclusively in a hospital setting during the delivery of primary specialized care.

Alternative methods of temporary cessation

In addition to the standard rubber tourniquet or an improvised tourniquet (using a makeshift lever), other methods are used:

• Digital arterial pressure: performed at typical points proximal to the site of injury (for example, on the upper limb or in the inguinal region).
• Maximum limb flexion: the joint (knee, hip, elbow) is flexed to the maximum and fixed in this position.
• Pressure bandage: using a gauze-cotton pad, optimal for stopping capillary or venous bleeding.
• Vascular clamp application: a hemostatic clamp is applied to the vessel stump directly in the wound (this method is available starting from the primary medical and emergency medical care stage).

Strict rules for tourniquet application

To safely use a hemostatic tourniquet, the following algorithm must be followed:

1. Before the manipulation, the injured limb must be elevated.
2. The tourniquet is placed as close as possible to the wound site.
3. To avoid skin pinching, a soft padding is placed under the rubber band.
4. Bleeding must be completely stopped by the very first tightened turn.
5. Subsequent turns are applied in a spiral in the proximal direction (up the limb). They overlap each other and serve exclusively to secure the tourniquet, after which the structure is fixed with a special fastener.
6. The applied tourniquet must be clearly visible (it must not be covered by clothing or bandages) and securely fastened.
7. A note indicating the exact time of its application must be attached to the tourniquet without fail.

Errors, time limits, and consequences

It is critically important to control the tension force and the time the tourniquet remains on the limb.

• Insufficient tightening does not occlude the arteries, but blocks the veins. This leads to a paradoxical effect — a sharp increase in venous bleeding from the wound.
• Excessive tightening severely injures soft tissues and can cause necrosis.

The maximum allowable exposure time of the tourniquet depends on the ambient temperature. In the warm season, it is no more than 2 hours, and in the cold season, it is reduced to 1–1.5 hours. Exceeding these time limits threatens irreversible ischemic changes.

Stages of care in bleeding

The scope of measures for stopping bleeding directly depends on the evacuation stage:

• First aid and primary pre-medical care: only temporary cessation methods are used (digital pressure, improvised tourniquet, limb flexion, pressure bandage).
• Primary medical and emergency medical care: the possibility of applying a clamp to the bleeding vessel in the wound is added to the above methods.
• Primary specialized care (trauma center): definitive cessation of external bleeding is performed using surgical methods.

Class and exam questions

What else to study on this topic

• Anti-shock measure complex and elimination of shockogenic factors
• Restoration of circulating blood volume (CBV) at various stages of evacuation
• Types and techniques of novocaine blockades in trauma
• Dosages of local anesthetics for various types of blockades
• Methods of transport immobilization at the pre-hospital stage

Other topics in the "Additional Topics" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.