Compartment pressure measurement

Indications

Compartment Syndrome Indications

• Consider whenever pain or paresthesia occurs in an extremity after:
  • fracture (most common risk factor) - can occur with open fracture
  • crush injury
  • immobilization
  • snake bites
  • burns
  • prolonged tourniquet application
  • fluid extravasation into a limb
  • soft tissue infection
  • extreme exertion

• Immediate threat is viability of nerve and muscle; later threat is infection, gangrene, rhabdomyolysis, renal failure

Contraindications

• Avoid areas of cellulitis.
• No absolute contraindications

Procedure

1. Contents of the pressure measurement kit
2. Remove contents from wrapping
3. Attach chamber to the pre-filled saline syringe
4. Place the aforementioned into the monitor/unit
5. Place needle onto chamber
6. Eject excess air, if present, from syringe
7. Zero the assembled unit at the angle you will be entering compartment
   1. Determine the appropriate site of injection to measure the desired compartment pressure
8. Clean the area with alcohol prep or chlorhexidine.
9. Insert, inject 2-3 drops of saline, and await measurement

Technique

• should be performed within 5cm of fracture site
• anterior compartment
  • entry point: 1 cm lateral to anterior border of tibia
  • needle should be perpendicular to skin
• deep posterior compartment
  • entry point: just posterior to the medial border of tibia
  • advance needle perpendicular to skin towards fibula
• lateral compartment
  • entry point: just anterior to the posterior border of fibula
• superficial posterior
  • entry point: middle of calf

Interpretation of Compartment Pressure

• Normal is <10 mm Hg
• Pressures <20 mmHg can be tolerated w/o significant damage
• Exact level of pressure elevation that causes cell death is unclear. It was previously thought pressure >30 mmHg was toxic although the "delta pressure" may be better predictor than absolute pressure

ΔPressure = [Diastolic Pressure] – [Compartment Pressure]

• ΔPressure < 30 mm Hg is suggestive of compartment syndrome

See Also

• Compartment Syndrome
• Compartment Pressure Measurement
• Burns
• Rhabdomyolysis
• Fractures (Main)

External Links

• Wheeles Textbook - Compartment Syndrome

Sources

• Image and procedure text cortesy of SoBro EM http://sobroem.com/2014/04/09/under-pressure/