CHAPTER 11: PRESSURE ULCERS AND PARAPLEGIA

Question 1

What is a pressure ulcer?

Answer 1

A wound acquired by prolonged unrelieved pressure over a bony prominence leading to ischaemic necrosis if the tissue pressure is greater than perfusion pressure.
It results from extrinsic factors and is propagated by intrinsic factors.
Muscle is more susceptible than skin.
Necrosis begins near bone leading to cone shaped area of tissue necrosis with apex at the skin.

Question 2

Where are common sites for pressure ulcers?

Answer 2

ischium 
greater trochanter 
sacrum 
heel 
malleolus 
occiput

Question 3

What is the pathogenesis of pressure ulcers?

Answer 3

Initiated by extrinsic factors, propagated by intrinsic factors

hyperaemia -> ischaemia -> necrosis -> ulceration -> (Marjolins)

EXTRINSIC
Pressure
Shear
Friction

INTRINSIC
General factors
- Age
- Malnutrition - protein, carb, Vit A,C, Zn, Fe
- Incontinence
- Immobilisation
- Systemic disease: diabetes, vascular disease, smoking

Wound factors

• ischaemia
• insensate
• decreased autonomic control
• infection

Question 4

Can you summarise the Waterlow score?

Answer 4

10 - at risk
15 - high risk
20 - very high risk

A

• Appetite
• Age,sex
• Ambulation
• Anaemia

B - Build and weight

C

• Skin type
• Steroids/NSAIDS
• Smoking
• Surgery (ortho / #below waist)
• Sensory disturbance (DM, paraplegia, CVA)

Question 5

Waterlow Score

Answer 5

Assesses pressure sore risk 
1. build, weight 
2. skin type 
3. continence 
4. mobility 
5. age sex 
6. malnutrition 
Special risks 
- Tissue malnutrition 
- Neurological deficit 
- Major surgery / trauma 
- Medication 

10-14 risk
15-19 high risk
20+ v high risk

OTHER SCORES Braden, Norton

Question 6

EPUAP - Grading of pressure sores (European Pressure Ulcer Advisory Panel)

Answer 6

I non-blanchable erythema
II partial skin loss
III full thickness skin loss
IV full thickness tissue loss (exposed tendon, muscle, bone)

Question 7

How can pressure ulcers be prevented?

Answer 7

Conservative, medical, surgical

Conservative

• skin care (clean, dry, urinary faecal diversion)
• pressure dispersion (low air loss mattress, Roho cushions)
• pressure awareness
• bed turn 2hrly, seated lift 10secs every 10mins

Medical

• positioning
• baclofen, diazepam, botox

Surgical
- release of contractures, cordotomy

Question 8

How do you manage pressure ulcers?

Answer 8

Grade 1-2 pressure relief

• minimise risk factors
• wound dressings - duoderm, opsite, mepilex, flamazine

Grade 3-4 - as above
- debride non-viable tissue

Dressing types

• wet - dry
• debriding (collagenase)
• antimicrobial (flamazine)
• occlusive (alginate, hydrocolloid)
• growth factors
• maggot therapy
• VAC

Question 9

How do you diagnose and treat osteomyelitis in pressure ulcers?

Answer 9

bone biopsy
bone scan
MRI - 98% sensitive, 90% specific

Treatment - aggressive debridement, 6wk Abx, reg dressings

Question 10

What are the indications for surgery on pressure ulcers?

Answer 10

Emergency - if pt septic

Non-emergency

• full investigation
• correct predisposing factors
• prevent recurrence postop
• do not op if deteriorating delay
• op if pt mobility improving
• VAC good adjunct
• motivated, young, clinically stable/improving, compliant
• postop physio, social support

Question 11

What are the principles of surgery on pressure ulcers?

Answer 11

• radical debridement
• obliterate dead space
• reconstruct with durable skin
• use readvanceable flaps, don’t burn bridges!
• design as large as poss
• suture lines away from pressure areas
• large drains 2wks

Question 12

What postop care is needed for pressure ulcers?

Answer 12

Drains 
Antibiotics 
Optimise nutritional status 
Special mattress 
Skin care 
Frequent turning
Pressure relief from op site 4-6wks 
Control of spasm 
Urinary and faecal diversion 
Gradual reintroduction of sitting over 2wks 
Patient education

Question 13

What complications are associated with pressure ulcer surgery?

Answer 13

haematoma 
infection 
dehiscence 
recurrence 
marjolins ulcer

Question 14

What flaps are available for pressure ulcer recon?

Answer 14

SACRAL
buttock rotation
gluteus maximus musculocutaneous (rotation / VY advancement) - sup and inf gluteal arteries
gluteus maximus muscle (type III) + SSG
SGAP
lumbosacral,
transverse back flaps

ISCHIAL
lower gluteal flaps FC/MC
Hamstrings VY advancement flaps (long head of biceps femoris type II, profunda femoris)
posterior (gluteal) thigh flap - medially or laterally based - descending branch of inferior gluteal artery
gracilis (small) pedicled
VRAM
TFL - Transverse or descending branch of the lateral circumflex artery

GREATER TROCHANTER
TFL (VY / Hatchet)
lat thigh FC - 1st lateral perforator of profunda femoris art
rectus femoris
vastus lateralis - transverse br of lateral circumflex femoral art, type I flap (free flaps)

Question 15

What papers are there regarding longterm outcome of pressure ulcers?

Answer 15

Yamamoto PRS 1997 FRCS plast notes