Extremity Compartment Syndrome
and Fasciotomy


Pathophysiology
Osteofascial compartments
- three in upper arm, three in forarm, two in thigh, three in lower leg.
- envelope of fascia over muscle and bone

Viscous Cycle
Elevated tissue pressure within confined space leads to tissue ischaemia
--> decreased capillary perfusion
--> compression of venules causes venous hypertension; causes transudation into tissue space, worsening problem
--> worsening tissue ischaemia stimulates vasodilation, which leads to further fluid transudation

Compartment Syndrome
Beyond the local problem, true compartment syndrome is a systemic response.
- circulating inflammatory process; hyperkalaemia from cellular necrosis, ARF with rhabdomyolysis, acidosis.

Aetiology
Often crush injury, trauma; limb compression.
Burns, casts, splints,
Bone fractures, vascular injuries
Systemic - SIRS, sepsis, extravasation of IV fluids, ischemia-reperfusion injury.
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Risk Fx
Popliteal vessel injury
Combined arterial / venous injury
Massive soft tissue injury; crushing
Prolonged ischaemia >4-6h
combined arterial, bone or soft tissue injury

Outcome
Depends on urgency treated, degree of irreversible tissue loss and necrosis
- peripheral nerves are more sensitive
PVD pts more prone to ischaemia
Shock and lib elevation reduce arteriovenous pressure gradient and worsen the problem.
Hypothermia and ice cause vasoconstriction, inhibiting perfusion further

Diagnosis

Pain, out of proportion to apparent insult,
- pain worse on passive stretch of compartment
Sensory and motor abnormalities, palpable tenderness / swelling, overlying skin change.
- sensory abnormality is an early change in significant compromise
Systemic features of hyperkalemia, acidosis and myoglobinuria.
Never rely on peripheral pulses or distal cap refil
- absent distal pulses mandate investigation for vessel injury.
Want the intervention to be before systemic features develop.

Direct measurement
Can measure with specificity
- Needle-catheter device on a syringe and manometer.
- Normal tissue pressures are 5-10mmHg
- Higher than this accompanied by compromise
- Up to 25-30mmHg requires intervention.

Management

Osmotic diuretics e.g. mannitol, ice packs, extremity elevation = probably all more harm than good.

Only effective therapy is fasciotomy
- as early and rapidy as possible.

Principles
Widely open compartments
Fully incise overlying epimysium and skin over entire length of incisions.
Avoid tight dressings, casts or splints


Leg Fasciotomy


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I perform a double-incision, 4 compartment fasciotomy

GA. Supine. Prophylactic Abx. Prepare and drape free covering the foot in a size 8 glove. 

I first make a medial incision

Posteromedial incision, 2cm posterior to posterior margin of tibia about 20 cm in through skin and fat so that all of the fascial incision can be performed under vision by retracting the superficial fascia with Langenbach retractors.

   I seek and protect the Long saphenous v & saphenous nerve

   I use Metzenbaum scissors to incise the deep fascia from the knee to the ankle to expose the gastrocnemius muscle and decompress the superficial compartment

   I then separate the fibers of Gastrocnemius and soleus and if necessary detach fibers of soleus from the middle third of the medial border of the tibia to expose the fascia of the deep compartment and incise its fascia.

Lateral

Skin incision 1/2 way between crest of tibia & fibula

Transverse fascial incision to identify Anterior & peroneal compartments

2x longitudinal incisions

Idenitfy & preserve common peroneal nerve during proximal faciotomy of anterior

compartment

Leave skin open. Apply saline-soaked gauze and elevate the limb. Splint the limb with a backslab and loose crepe dressing

Consider delayed primary closure after 3-5/7

Liberal use of SSG if closure difficult


Thigh?

Uncommonly needed; orthopedic territory

Open anterior, medial and posterior compartments using an anteriolateral longitudinal skin incision along the iliotibial tract.


Below elbow?
Uncommon; volar and dorslal compartments need decompression
S shaped incision over wrist to avoid prolbmeatic contractures.


Complications

Infection quite comon often due to underlying necrosis when present rather than fasciotomy.


How do you measure the compartment pressure in the leg

Slit a 14G venous cathether, manometer tubing, a 3-way tap and pressure transducer (sphingnomanomter or electronic transducer).

Prepare skin. 2ml 1% lignocaine. Insert catheter and withdraw trocar.

Inject saline into catheter

Prime manometer tubing with saline and connect via a 3-way tap to the catheter and pressure transducer

 

How do you measure the compartment pressure in the leg

I use the Whitesides technique

Equipment: Mecurary manometer, two plastic IV extension tubes, two 18G needles, one 20ml syringe, one 3 way tap and one bag saline.

Set up: Use one needle to vent the saline bag. Connect one extension tube to the three way tap and connect the other end to the needle. Connect the 20mL syringe to the other limb of the 3-way tap and close off the third limb

Aspirate saline into the extension tubing to fill about half its length and then close off the tap so that the saline is not lost

Use the last extension tubing to connect the final limb of the 3 way tap to the mercurary manometer.

Remove the syringe and fill it with 15ml of air and re-connect.

The needle is inserted into the limb and the three way tap opened to form a T connection between the manometer, tissue and syringe.

Depress the syringe slightly to flush the tip of the needle.

Apply gentle pressure on the syringe and read the pressure when the meniscus is flat.

The alternative is to use an electronic transducer.

14G venous cathether, manometer tubing, a 3-way tap and pressure transducer (sphingnomanomter or electronic transducer).

Prepare skin. 2ml 1% lignocaine. Insert 14G canula and withdraw trocar.

Inject saline into canula to prime it

Connect one end of the manometer tubing to a 3 way tap and prime manometer tubing with saline to ensure that there are no bubbles and connect the other end to the canula in the tissues.

Connect the three way tap to a primed and zeroed electronic pressure transducer.