2 The condition, current treatments and procedure
2.1 Stroke (ischaemic stroke and intracerebral haemorrhage) is an acute neurological event presumed to be vascular in origin and causing cerebral ischaemia, cerebral infarction or cerebral haemorrhage. Subarachnoid haemorrhage (SAH) is a haemorrhage from a cerebral blood vessel, aneurysm or vascular malformation into the subarachnoid space.
2.2 Both conditions can interrupt blood flow to the brain, damage brain cells and cause abnormalities of thermoregulation and an abnormally high body temperature (neurogenic fever). The abnormally high temperature may result in secondary neurological injury and is associated with worse outcomes, greater morbidity and mortality.
2.3 Diagnosis and initial management of stroke is described in NICE's guideline on stroke and transient ischaemic attack in over 16s. Current treatments for managing fever after stroke or SAH include identifying and treating a cause, antipyretic medications and standard physical methods of cooling such as fans and cooling blankets to lower body temperature.
2.4 In this procedure, a temperature modulation device is used to maintain the patient's core temperature within normal limits (37.0±0.5oC). Either surface techniques (such as heat exchange cooling pads) or internal techniques (such as an endovascular cooling device) may be used. Heat is exchanged between the patient and the device to allow the body temperature to be controlled to a pre-set point determined by the clinician.
2.5 This procedure aims to reduce brain injury and improve neurological outcomes after stroke or SAH by maintaining normothermia with precise temperature control.