Pressure sores

Question 1

Why do normal people not get ulcers?

Answer 1

Most people, even subconsciously when asleep, will move every time a part of their body starts getting uncomfortable due to constant pressure.

Patients who can’t move will develop pressure ulcers within an hour so you must watch out for frail patients who are too weak to move, under anaesthesia or sedated on intensive care.

Question 2

Define pressure ulcer.

Answer 2

Pressure ulcers have been defined by the NPUAP and the EPUAP as localised injury to the skin and/or underlying tissue usually over a bony prominence, as a result of pressure or of pressure in combination with shear.

Question 3

What are the risk factors for pressure ulcers?

Answer 3

• Immobile patients - use of splints, plaster casts etc.
• Sensory impairment
• Old age
• Surgery
• Intensive care stay

Question 4

Are pressure ulcers painful? What is the onset?

Answer 4

Caused by prolonged pressure on affected site. Tend to be exquisitely tender byt not necessarily painful if no pressure is applied.

Pressure ulcers develop RAPIDLY (hours or days), but can have a more indolent course depending on how much pressure is put on for how long.

Question 5

What is the aetiology of pressure ulcers?

Answer 5

Pressure –> ischaemia of tissues, most commonly over bony prominences. Ischaemia may be increased by poor perfusion to skin and tissues e.g. in HF, sepsis, hypotension, PVD.

Pressure ulcers have traditionally been thought to develop through the interplay of 4 main factors:

1. pressure (duration and intensity),
2. shear (sliding down in bed) ,
3. friction, and
4. moisture

Question 6

How are ulcers graded?

Answer 6

European Pressure Ulcer Advisory Panel (EPUAP) grades:

1. Non-blanching erythema of intact skin
2. Partial thickness skin loss or blistering
3. Full thickness skin loss. Subcutaneous fat may be visible, but not underlying tendon, bone, muscle etc
4. Full-thickness tissue loss with involvement of bone/muscle/tendon.May be covered with thick slough* or eschar**.

Question 7

Name 3 types of ulcer bases.

Answer 7

slough - yellow/white material in the wound bed; it is usually wet. A mixture of fibrin, cell breakdown products, serous exudate, leucocytes and bacteria. Does not necessarily imply infection.

eschar - tan/brown/black dead tissue that sheds or falls off from the skin; common in pressure sores

granulation tissue - deep pink gel-like matrix contained within a fibrous collagen network and is evidence of a healing wound

Question 8

Name 3 stages of wound healing.

Answer 8

1. Granulation
2. Scar formation
3. Epithelialisation

Inflamed margins suggest extension

Question 9

What do the edges of an ulcer tell you about it?

Answer 9

• Shelved/sloping - healing
• Punched out - ischaemic or syphilis
• Rolled/everted - malignant
• Undermined - TB

Question 10

Name the three most common locations of pressure sores.

Answer 10

• sacrum
• greater trochanter
• heel

Question 11

How common are pressure ulcers?

Answer 11

• prevalence in hospitalised patients of 4.7% to 32.1%.
• highest in >85 year olds
• most on sacrum, coccyx or heels

Question 12

What are the signs of pressure sores on examination?

Answer 12

• An area of non-blanchable erythema
• Marked localised skin changes
• A wound of varying severity on an anatomical site that is known (or suspected) to have previously been exposed to significant unrelieved pressure.

Question 13

How do you manage a pressure sore?

Answer 13

• Pressure-reducing aids + repositioning - patients should not be positioned on their wound and be repositioned every 2 hours. Dry skin and use of protective creams. Involve physiotherapy and occupational therapy.
• Hygiene and cleansing + dressing - hydrocolloid dressings (promote healing as they have a gel that covers the ulcer and keeps it moist and protected)
• Analgesia
• Dietary optimisation - to ensure adequate calorie and total protein intake. Should be done every 3 months for patients at risk of malnutrition

Other:

• Antimicrobial therapy (for stage 3 or 4 ulcers, unsuitable for surgery)
• Surgery - Debridement of necrotic tissue (if pt suitable for surgery), surgical debridement and reconstruction with flap formation where ulcers are not healing

Question 14

What investigations would you do for a pressure ulcer?

Answer 14

FIRST LINE: Clincial diagnosis - look for features of a pressure ulcer

Wound swab - positive culture in infection BUT often shows colonisation and not actual infection

ESR- >100 mm/hour in osteomyelitis

WBC - >15.0 x 10^9/L in osteomyelitis but not confirmatory for pressure ulcers

Serum glucose - exclude diabetes

Deep tissue biopsy - to check for infection. But not always practical

MRI - where there is bony involvement