Cerebral Haemodynamics and Orthostatic Response to Upright Posture in Acute Ischaemic Stroke (CHORUS)

Stroke is the leading cause of adult disability and mortality in Australia. The majority of strokes are ischaemic in nature and occur when a blood vessel to the brain is occluded, usually by a clot.

Cerebral blood flow in acute ischaemic stroke is highly dynamic, and factors that either impair or promote cerebral blood flow during the acute phase may directly affect the infarct size and associated clinical deficit. Lowering the head of the bed in the early hours of stroke may theoretically assist flow to the ischaemic tissue. Conversely, there is growing support for early mobilisation after stroke with the potential to reduce cerebral blood flow and decrease infarct size. Currently there is no consensus and no clinical guidelines on the safety of early upright posture when caring for acute stroke patients. Against a backdrop of a number of large, international clinical trials that are studying the effects of early activity (AVERT) or bed rest for 24 hours (HEADpost) to improve recovery, further evaluation of the extent and clinical relevance of orthostatic changes in cerebral blood flow in acute ischaemic  stroke using transcranial Doppler ultrasound is warranted.