Orthostatic hypotension following spinal cord injury: understanding clinical pathophysiology

Motor and sensory deficits are well-known consequences of spinal cord injury. During the last decade, a significant number of experimental and clinical studies have focused on the investigation of autonomic dysfunction and cardiovascular control following spinal cord injury. 

Numerous clinical reports have suggested that unstable blood pressure control in individuals with spinal cord injury could be responsible for their increased cardiovascular mortality. The aim of this science investigation is to outline the incidence and pathophysiological mechanisms underlying the orthostatic hypotension that commonly occurs following spinal cord injury. 

We describe the clinical abnormalities of blood pressure control following spinal cord injury, with particular emphasis upon orthostatic hypotension. Possible mechanisms underlying orthostatic hypotension in spinal cord injury, such as changes in sympathetic activity, altered baroreflex function, the lack of skeletal muscle pumping activity, cardiovascular deconditioning and altered salt and water balance will be discussed. 

Possible alterations in cerebral autoregulation following spinal cord injury, and the impact of these changes upon cerebral perfusion are also examined. Finally, the management of orthostatic hypotension will be considered.