[1][2][3][4] Whether resulting from traumatic vessel disruption, tourniquet application, or shock, the extremity is exposed to an enormous flux in vascular perfusion during a critical period of tissue repair and regeneration.
When tissues do not have adequate oxygen delivery (i.e., are ischemic), they revert to less efficient metabolic processes, producing lactic acid.
Recognizing this, surgeons frequently prophylactically release (i.e., incise) fascia of arm and leg fascial compartments after repair of a proximal vascular injury.
[citation needed] Emergency field tourniquets have been used for many centuries, and have seen a resurgence in the recent combat operations in Afghanistan and Iraq, as well as expanded use in civilian trauma and mass casualty settings.
Expedient and widespread tourniquet use in the modern combat setting is frequently cited as a primary driver for increased survival following major battlefield trauma.
They can result in tissue necrosis if kept in place for long periods, and should only be applied after other methods to control bleeding (e.g., elevation or direct pressure to the wound) have failed, except in settings where time does not allow waiting.
[citation needed] In the same way that external compression tourniquets reduce or eliminate arterial blood flow, aortic cross clamping has the same effect.
[citation needed] Available hind limb IR animal model are either artery vein ligation or tourniquet application (by rubber band or O-ring).