What are bedsores? Causes of bedsores

The disease of bedsores is generally caused by physical reasons. Long-term pressure causes the squeezed cells to lack oxygen and die. If the body lacks nutrition, it will also cause damage to the body's muscles. Lack of muscles is equivalent to no protection, and this will lead to bedsores over a long period of time.

1. Stress Factors

(1) Vertical pressure is the main cause of pressure ulcers. The local tissue is subjected to continuous vertical pressure, especially on the protruding parts of the bones. Pressure sores may occur if you are bedridden or in a wheelchair for a long time, the padding in the splint is not placed properly, the plaster is uneven or has debris, or the local area is under pressure that exceeds the normal capillaries for a long time (generally speaking, the blood vessels under the skin can withstand a pressure of about 32 mmHg. If the pressure exceeds this, the local blood vessels may twist and deform, affecting the blood flow, resulting in ischemia).

(2) Friction Friction acts on the skin and can easily damage the skin's stratum corneum. When the patient is moving in bed or sitting in a wheelchair, the skin may be subjected to the reverse resistance friction of the bed sheets and the surface of the wheelchair cushion. If the skin is scratched and then soaked with sweat, urine, feces, etc., pressure sores are likely to occur.

(3) Shear force Shear force is a force applied to an object that causes a plane to slide in a parallel and opposite direction. It is the sum of friction and vertical pressure. It is closely related to body posture. For example, when you lie flat and raise the head of the bed, your body slides down, and there is parallel friction between the skin and the bed. Combined with the gravity in the vertical direction of the skin, shear force is generated, causing local skin blood circulation disorders and pressure sores.

2. Nutritional status

Systemic nutritional deficiencies, muscle atrophy, lack of protection of pressure areas, such as prolonged fever and cachexia.

Systemic nutritional disorders and insufficient nutritional intake lead to reduced protein synthesis, negative nitrogen balance, reduced subcutaneous fat, and muscle atrophy. Once under pressure, the skin at the bony protrusions has to bear the external pressure and the squeezing force of the bony protrusions on the skin. The compressed areas lack the protection of muscle and fat tissue, causing blood circulation disorders and pressure sores.

3. Reduced skin resistance

The skin is often exposed to physical stimuli such as moisture and friction (such as improper use of plaster bandages and splints, incontinence, wrinkled sheets, debris on the bed, etc.), which reduces the skin's resistance.