Compartment Syndrome

Compartment Syndrome (CS)

• CS is a limb threatening condition caused by raised pressure within a facial compartment.
• This causes compression of vessels, muscles and nerves within the compartment.

Presentation:

Symptoms:
• Pain out of proportion

Signs:
• Pain with passive stretch
• Paraesthesia and hypopthesia
• Tense compartment (woody hardness)
• Congestion of digits
• Paralysis late signs
• Absent pulses

Common locations (?in order of prevalence – find literature):

• Forearm (esp volar compartment)
• Lower leg (esp anterior compartment)
• Thigh
• Upper arm
• Hand
• Foot
• Back
• Abdomen
• Buttocks

Examination

• Feel the affected limb segment noting how tense it is
• Stretch of the affected compartment (?see below for specifics)

Investigations

• X-ray to exclude underlying fracture
• Send bloods: FBC, ELFTs, CK (and G&H if high likelihood of acute CS and consequent operative intervention)
• Urine dipstick for myoglobinuria

Management

• Relieve/cut any constricting dressing or cast (if the causative factor)
• If underlying fracture identified, reduce and splint/cast and reassess for CS
• Elevate affected compartment to the level of the heart
• IV access: fluids, analgesia, anti-emetics
• Refer to the orthopaedic or plastic teams promptly*

*In the obtunded patient refer at the first suspicion of CS as the patient requires invasive compartment measuring to confirm the diagnosis (?explain/show how to do measurements here or LLL or link to separate page)

Late Presentation / Diagnosis

• After 8 hours of established CS refer immediately to the orthopaedic or plastic teams; the risks of invasive measurements and compartment release may outweigh the benefits by this time due to muscle death2.

Pearls

Have a high index of suspicion in:
• Tibial shaft fractures (CS occurs in up to 9%1)
• Pain not relieved with 0.2mg/kg iv morphine bolus
• The obtunded patient (inebriated, comatose, sedated, polytrauma, paralysed)

And lastly, remember, CS is a clinical diagnosis (except in the obtunded patient) and if you have a clinical suspicion refer immediately to the surgeons.

Life long learning (L.L.L.)

Acute compartment syndrome is a devastating condition caused by raised pressure within a facial compartment leading to decreased perfusion with risk of irreversible muscle and nerve damage.

Epidemiology

• Trauma (fractures 69%3, crush injuries, burns, contusions, gunshot wounds)
• External compression (tight casts & dressings)
• Bleeding disorders
• Reperfusion injury (tourniquets, surgical thrombectomy)
• Extravasation of IV fluids
• Arterial injury
• Snake bite
• Anabolic steroid use

Anatomy

Muscles are contained within inelastic fascial sheaths called compartments. CS can occur wherever there is a closed muscle compartment – each compartment is a different colour below.

Pathophysiology

When the pressure within a fascial compartment increases (muscle swelling, bleeding etc), it can exceed capillary pressure and circulation is compromised. This results in ischemic injury to the muscles and nerves within the fascial compartment.
Normal tissue pressure ranges between zero and 10 mmHg. Capillary blood flow within the compartment may be compromised at pressures > 20 mmHg. Muscle and nerve fibers are at risk for ischemic necrosis at pressures >30mmHg. These pressures may still be tolerated — depending on the perfusion pressure, hence a recent trend towards using delta pressures, although most treatment recommendations are still based on absolute pressures:
What is the delta value?

Delta value (or delta p) = Diastolic blood pressure – Intracompartmental pressure

Ischemic injury to muscles and nerves occurs after 4 hours of complete ischemia. This becomes irreversible at some point over the next 4 hours (i.e. 4-8 hours after the onset of ischemia), resulting in local rhabdomyolysis and neuropraxis progresses to axonotmesis as nerve injury worsens

Complications include:
• Gangrene or loss of limb viability requiring amputation
• Ischemic contracture and loss of function
• Rhabdomyolysis and renal failure
Assessment

History

Suspect if on the epidemiology list as above, especially fractures, and they have pain out of proportion to their injury.

Examination

• Pain is exacerbated by passive stretching, which is the most sensitive sign.
• The extremity may be swollen and affected compartments may feel tense and tender on palpation.
• Assess loss of sensation by light touch and two-point discrimination, rather than just pinprick, which is less sensitive.
• Refer to a surgeon if compartment syndrome is suspected — do not rely on clinical signs — have a high index of suspicion!

• Palpable distal pulses and normal capillary refill does not exclude compartment syndrome. Pulse oximetry is insensitive and is not recommended in the detection of compartment syndrome.
Investigation

X-rays: Are used to identify underlying fractures but cannot diagnose CS.

Compartment pressure measurement: A commercial device like the Stryker STIC Device is probably the easiest and most accurate means of measuring compartment pressures.
Should be performed within 5cm of fracture site
• anterior compartment
o entry point
• 1cm lateral to anterior border of tibia within 5cm of fracture site if possible
o needle should be perpendicular to skin
• deep posterior compartment
o entry point
• just posterior to the medial border of tibia
o advance needle perpendicular to skin towards fibula
• lateral compartment
o entry point
• just anterior to the posterior border of fibula
• superficial posterior
o entry point
• middle of calf within 5 cm of fracture site if possible

[insert stryker video – LITFL]

Alternatively:
• Compartment pressures may also be obtained using an angiocath connected to a blood pressure transducer (e.g. arterial line set up).
• Other options for measuring compartment pressures include the needle technique, the wick catheter, and the slit catheter.
• The needle technique according to Perron et al (2006) is described as follows
[insert angiocath video – LITFL]
The needle technique has the advantage that it can be performed with items that are readily available in every ED. An 18-gauge needle is attached to an intravenous extension tube and then to a stopcock. Approximately half the tubing is filled with sterile saline — being certain that air is not allowed into the tubing. A second intravenous extension tube is attached to the 3-way stopcock with the opposite end attached to the blood pressure manometer. The needle is then placed in the compartment and the apparatus kept at the level of the needle. The stopcock is then turned so that it is open in the direction of the intravenous tubing on either side of a syringe. The syringe filled with air is slowly compressed, causing air to move into both extension tubes. The meniscus created by the saline in the extension tube attached to the 18-gauge needle is watched carefully for any movement. As soon as movement occurs in the fluid column, the compartment pressure is read from the blood pressure manometer. This technique, although simple to perform with minimal equipment, may be inaccurate.
Management
• Relieve/cut any constricting dressing or cast (if the causative factor)
• If underlying fracture identified, reduce and splint/cast and reassess for CS
• Elevate affected compartment to the level of the heart
• IV access: fluids, analgesia, anti-emetics
• Send bloods: FBC, ELFTs, CK (and G&H if high likelihood of definite acute CS and consequent operative intervention)
• Urine dipstick for myoglobinuria
• Refer to the orthopaedic or plastic teams promptly*

Late Presentation / Diagnosis

After 8 hours of established CS, severe muscle necrosis and permanent nerve injury will have occurred, performing a dermofasciotomy has increased risk of infection, amputation (twice as likely) and death (three times as likely)2 and is unlikely to avoid severe muscle contracture. The decision to use invasive investigations or perform operative release needs the deliberation of the most experienced surgeon.

Question bank (goes towards LITFL injury nano degree)

A 20 year old male sustains a closed tibial shaft fracture in a tackle playing soccer. Which of the following measurements would be concerning for an evolving compartment syndrome?

A) Anterior compartment measurement of 29, with diastolic pressure 58
B) Anterior compartment measurement of 25, with diastolic pressure of 60
C) Anterior compartment measurement of 25, with diastolic pressure of 54
D) Anterior compartment measurement of 28, with diastolic pressure of 72
E) Anterior compartment measurement of 22, with mean arterial pressure of 70

References

1) Park et al 2009 J Orthop Trauma. 2009 Aug;23(7):514-8. doi: 10.1097/BOT.0b013e3181a2815a.
Compartment syndrome in tibial fractures.
2) Ritenour et al 2007 The Journal of TRAUMA Injury, Infection, and Critical Care
Complications After Fasciotomy Revision and Delayed Compartment Release in Combat Patients
3) Konstantakos et al 2007 Am Surg
Diagnosis and management of extremity compartment syndromes: an orthopaedic perspective.
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