crush syndrome

Last reviewed 01/2018

This is a condition that may occur if a large bulk of muscle is crushed, e.g. if a patient is crushed by falling masonary, or if a tourniquet is left on for too long.

When the crushing force is relieved then there is release of cytochrome c from the muscles. This is believed to mediate its effects on the kidneys by blocking the kidney tubules, and/or causing renal artery spasm and then consquent tubular necrosis.

This condition is characterised by the development of a profound shock. If a limb has been trapped, it will become pulseless on release. Later, it will become red, swollen and blistered. There may be loss of sensation and muscle power.

Acute renal failure may set in during the first sixty hours after release. Low-output uraemia with acidosis is the result. If renal function does not return then the patient may become increasingly uraemic and die within 14 days. Renal dialysis may be required in these patients.

In order to avoid the development of this syndrome any limb that has been severely crushed should be amputated. Similarly if a limb has had a tourniquet on for more than 6 hours then it should be amputated. Any amputation must be carried out above the site of compression and before the crushing force is removed.

If the compression force has already be removed then the limb must be cooled and the patient treated for renal failure and shock.