Tourniquets: Uses and Precautions

Abstract

Modern pneumatic tourniquets consist of three basic components: a cuff wrapped around a patient's limb and then inflated, a compressed gas source, and a mechanism with a pressure gauge to maintain the desired cuff pressure (Figure 1). Arterial tourniquets are used to reduce blood loss and provide better operative conditions during extremity surgery. Tourniquets are also used to prevent systemic toxicity of drugs that are administered in high doses into the isolated limb, such as during intravenous regional anaesthesia, intravenous regional sympathectomy in the management of complex regional pain syndromes, and isolated limb perfusion with cytotoxic drugs (e.g. melphalan) in the treatment of localized cancers (e.g. melanoma and soft tissue sarcoma) in the extremities. There is no place for arterial tourniquet as a first aid measure for severe haemorrhage that can instead be controlled effectively by elevating the limb and applying well-padded pressure bandages over the wound. The risks and benefits of a tourniquet must be assessed before its use, because the risks increase in patients with co-morbidities (peripheral vascular disease, old age), and with high tourniquet pressure and prolonged duration of tourniquet application.