الفهرس 
Tissue pressureOnly 14 pages are availabe for public view
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Abstract
A compartment syndrome is defined as a condition in which high pressure within a closed fascial space causes reduced blood flow with nerve and muscle ischaemia. Untreated compartment syndrome leads to ischaemia with necrosis, contractures, myofibrosis and irreversible functional impairment in the involved part of the limb.
Compartmental syndrome is produced when the tissue pressure within a limited space rises to the point where the circulation and function of the tissues within that space are compromised. There are two prerequisites for the production of a compartmental syndrome: (a) an envelope limiting the available space and (b) a cause of increased pressure within that envelope.
Direct measurements of normal capillary pressure were found to be between 20 and 33 mm Hg, when tissue pressure exceeds these values, capillary blood flow is reduced by microvascular occlusion.
Certain anatomical locations are particularly predisposed to the development of a compartmental syndrome. This predisposition may result from the limited compliance of the compartment. The muscles of the leg and forearm are often exercised vigorously, thus, their compartments are potential sites of compartmental syndromes from intensive use of muscle.
Compartment syndrome can be classified as incipient, acute and chronic depending on the aetiology of the increased pressure and the duration of the symptoms.
The five P’s (pulselessness, pallor, paralysis, parathesia and pain) have been advocated as clinical signs of a developing compartment syndrome. These particular symptoms and signs are present during a well established compartment syndrome.
Motor function is the first nerve function to be lost when a limb is rendered ischemic. Irreversible muscle fiber changes occur early as 6 hours after the onset of tissue ischemia.
The most reliable symptom is pain which is persistent, intense and of a deep aching nature. If the syndrome is exercised induced the pain can usually be controlled by decreasing exercise intensity or ceasing activity altogether. The compartment will feel tense on palpation, and the level of pain can be exacerbated by passive stretching of the muscles involved.
Laboratory and imaging studies are not helpful in diagnosis true CECS, but may be ordered to rule out other causes of lower leg pain on an individual case-by-case basis.
Many techniques are available for measuring tissue pressure including Whitesides (needle manometer) technique and the stryker technique. All have the advantage of objectively measuring the tissue pressure in an enclosed osseofacial compartment.
Other methods for diagnosing CS include direct nerve stimulation, magnetic resonance imaging, laser Doppler flowmetry and near-infrared-spectroscopy.
The objective of treatment of a compartmental syndrome is to minimize deficits in neurological function by promptly restoring local blood flow, usually by surgical decompression.
Surgical decompression of all limiting envelopes is usually indicated in the presence of (a) a characteristic clinical picture of a compartmental syndrome, or (b) an ambiguous clinical picture in the presence of a measured tissue pressure in excess of 40 mm Hg, provided the patient has a normal pressure tolerance.
Several principles are applicable to the surgical decompression of all acute compartmental syndromes. The procedure is performed without a tourniquet to avoid prolonging the period of ischemia and to permit the surgeon to assess the degree to which the local circulation is restored by decompression.
Each potentially limiting envelope, including skin, is opened over the entire length of the compartment; all muscle groups should be soft to palpation at the end of the procedure. If muscle tenseness remains after the skin and facial incisions have been made, epimysiotomy may be required to complete the surgical decompressions. The debridement of muscle is kept at a minimum at the time of surgical decompression unless there is obvious muscle necrosis.
The skin is left wide open to prevent the development of a ”rebound” compartmental syndrome with the skin as the limiting envelope and to prevent post-ischemic swelling.
Exertional compartment syndrome initially is treated differently from trauma induced compartment syndrome. A trial of conservative treatment may result in resolution of symptoms in exertional compartment syndrome. The conservative treatment mainly involves a decrease in, activity or load to the affected compartment. The activity level gradually is increased, depending on the symptomatology.
When the condition becomes chronic, lasting 6 months or longer, surgical intervention is the only effective option. Surgical irtervention has a good success rate. In the anterior compartment of the leg, success rates usually exceed 85%, while in the deep posterior compartment success rates are approximately 70%.
After surgical intervention to release the involved compartment, range of motion activity often will begin immediately or within 3 days postsurgery.
Hyperbaric oxygen therapy is used for treatment of CS as it increases tissue oxygen tensions in hypoxic tissues to levels which make it possible for the host responses to become functional. It also reduces oedema through oxygen induced vasoconstriction while maintaining oxygen perfusion and supports tissue healing in a similar mechanism by allowing oxygen delivery when perfusion pressure is low.