Pressure Ulcers Flashcards
A greater understanding of the causes of pressure ulcers is a fundamental issue in preventing them occurring- why is this important?
Pressure ulcers cause unnecessary suffering for the patient and can increase hospital stay considerably
They are expensive to treat and to prevent
4% of NHS spending
what is a pressure ulcer
“A pressure ulcer is localised injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure in combination with shear. A number of contributing or confounding factors are associated with pressure ulcers.”
where do pressure ulcers occur
Over hard bony areas covered by a thin layer of tissue which is in contact with a hard surface e.g. sacrum or heels
describe pressure ulcer aetiology/ pressure ulcer cycle
unrelieved pressure starts the cycle
blood vessels occlude, histamine is released, and reactive hyperaemia occurs
there is prolonged pressure damage to microcirculation
the lymphatic system is damaged, cell membranes rupture, toxins are released and there is cell and tissue damage
what are the 4 causes of pressure damage
Mechanical Forces
Poor patient handling
Reduced Mobility
Reduced Tissue Tolerance
what are mechanical forces that can cause pressure damage
- Pressure
- Shear
- Friction
what can be reasons for reduced mobility which may lead to pressure damage
- Surgery
- Lower level of consciousness
- Medication
- Illness
- Neurological problems
- Poor muscle strength
what can cause reduced tissue tolerance
- Poor nutrition
- Chronic/acute illness
- Increasing age
- Poor oxygen perfusion
- Medication
- Obesity
- Emaciation
- Poor skin care
- Incontinence
Pressure Ulcers occur due to a combination of both intrinsic and extrinsic factors- what is the difference
Intrinsic: Inherent to patient: co-morbidities, existing or previous damage, impairment, age
Extrinsic: environmental/external factors, we can have a positive effect on
examples of intrinsic factors
- Nutritional status
- Build
- Age
- Sensory impairment
- Incontinence
- Infection
- Reduced mobility
- Circulatory disorders
- Dehydration
- Mental status
- Neurological disease
examples of extrinsic factors
- Pressure
- Shear
- Friction
- Moisture
- Restricted Mobility
- Surgery
- Poor moving and handling
- Medication
- Inappropriate positioning
- Poor hygiene
- Inappropriate clothing
what is Interface Pressure
the pressure of the body pushing down onto a hard surface; usually over a bony prominence
can low pressure for long periods of time cause more or less damage than high pressure for short periods of time and why?
Low pressure for long periods of time can cause greater damage than high pressure for short periods of time. Sustained pressure interrupts blood supply to tissues
Lack of oxygen & nutrients from perfusion cause tissue damage & death
Lack of white blood cells increase risk of infection and delay healing
what are shearing forces
A stretching force which has a detrimental effect on circulation due to pulling the skeletal frame downwards
how can shearing forces damage skin
The skin adheres to hard external surface (bed, trolley, chair)
Leads to tearing of capillaries & damage to circulation
Tissue is pulled in opposing direction to the skeleton
This causes blood vessels to tear and compounds the effects of pressure
Can be caused by poor positioning and manual handling