Compartment Syndrome

Question 1

Define compartment syndrome.

Answer 1

Elevated interstitial pressure within a closed fascial compartment, resulting in microvascular compromise

Question 2

List 8 causes of compartment syndrome.

Consider internal (5) and external (3) causes.

Answer 2

INTERNAL:
Trauma (e.g. bleeding, fractures, entrapment)
Muscle oedema
Myositis
Intra-compartmental administration of fluids/drugs
Reperfusion

EXTERNAL:
Casts/bandages
Circumferential full thickness burns
Impaired consciousness, e.g.
-Drug/alcohol abuse
-Iatrogenic
-Surgery positioning

Question 3

Describe the pathophysiology of compartment syndrome. (5)

Answer 3

1. Interstitial pressure increases until pressure within the fascial compartment exceeds pressure in capillaries
   a. This blocks capillaries
   b. Reduced blood flow causes reduced tissue perfusion
2. Muscles become ischaemic, leading to increased endothelial permeability
   a. This causes oedema
   b. This causes leakage of fluid into interstitial space
   c. This causes further increase in interstitial pressure
3. Interstitial pressure and fluid leakage creates a worsening cycle
   a. Ischaemia progresses to necrosis in 4 hours
4. Nerves also become ischaemic
   a. This causes neuropraxia
5. Arterial supply is compromised in end stage compartment syndrome
   a. This causes critical limb ischaemia
   b. This can cause loss of limb

Question 4

At what point does nerve/muscle damage occur in compartment syndrome?

At what point does it become irreversible?

Answer 4

Damage occurs at 4 hours

Becomes irreversible ~8 hours

Question 5

Describe the clinical features of compartment syndrome. (8)

Answer 5

THE 5 PS:
Pain (out of proportion with injury; on passive stretching)
Pallor
Parasthesia
Paralysis
Pulselessness

OTHER SYMPTOMS:
Swelling
Shiny skin
Autonomic responses (e.g. sweating, tachycardia)

Question 6

Describe the clinical features of end stage compartment syndrome. (4)

Answer 6

Stiff, fibrotic muscle compartments
Impaired nerve function
Limb clawing
Loss of function

Question 7

What investigations would you do for compartment syndrome? (2)

Answer 7

Compartment pressure

• Normal: 0-4 mmHg
• Compartment syndrome: 30+ mmHg

Difference between diastolic BP and compartment pressure
-Normal: <30 mmHg

Question 8

How would you treat compartment syndrome? (5)

Answer 8

Open any constricting dressings/bandages

Surgical release:

• Full length decompression
• Debridement of necrotic muscle

Delayed wound closure

Skin grafting

Perioperative care

Question 9

Describe the non-surgical aspects of compartment syndrome treatment. (6)

Answer 9

Adequate hydration
Address fluid loss
Monitor/regulate electrolytes
Correct acidosis
Monitor myoglobinuria
Monitor renal function

Question 10

How would you manage compartment syndrome with late presentation?

Answer 10

Non-operative treatment

Splint into a position of function (so non-functional limbs can still be used slightly)