Definition of pressure ulcer
A pressure ulcer is an ischemic ulceration of the skin caused by prolonged, excess pressure between the soft tissue over bony prominences of the body and a support surface.This continuous, excess pressure can hinder blood circulation and lead to the formation of a pressure ulcer.
There are four different stages of pressure ulcer, from simple erythema to deep tissue necrosis (NPUAP classification).
The pressure exerted on tissue can be surface.doubled:
– by shearing, which is responsible for stretching blood vessels. This stretching, which reduces blood flow, is caused by the pelvissliding down along the support
-by friction (force exerted between 2 surfaces moving
To prevent shearing and friction, the person must be repositioned correctly in his or her chair.
Removing pressure causes hyperemia (increase in blood flow) to occur locally.This reaction is temporary and lasts depending on how long the tissue was subjected to pressure.
Formation of pressure ulcers
The formation of pressure ulcers represents an inherently multifactorial system (general state of health, pathologies, mobility, nutrition, moisture) associated with the occlusion of blood vessels by pressure.
– The primary physiopathogenic risk factors are:
– Reduced mobility
– Deterioration of microcirculation
– Deterioration of skin with:
– loss of thickness of dermis and epidermis
– loss of elasticity between the dermis and