Abstract
Post dural puncture headache and hypertension (PDPH) is a low pressure headache closely related to Cerebrospinal fluid (CSF) hygrodynamics. PDPH occurs because of a CSF leak that occurs as a consequence of a dural puncture. The leakage of CSF produces traction on the brain and the meninges and causes compensatory cerebral vasodilatation resulting in a headache. Cerebrovascular autoregulation is a gradual process which minimizes intracranial pressure changes in the presence of systemic blood changes. Cerebral autoregulation prevents the cerebral blood vessels from dilating in moderate hypertension. There is a loss of autoregulation in end stage intracranial hypertension where there are passive changes in cerebral blood flow and cerebral blood volume, when there are changes in the systolic pressure. Hypertensive encephalopathy is associated with the breakdown of the blood brain barrier and is a complication of chronic severe hypertension Since the cerebral venous system has no valves fluctuations in the systemic venous pressure will directly affect CSF pressure. There is increased drainage of CSF into the venous system secondary to increased CSF pressure in severe systemic hypertension.. It appears that CSF volume is decreased in the presence of systemic hypertension however it is still unclear if the CSF pressure in systemic hypertension is decreased as well. Clinical data on post dural puncture headaches in the presence of hypertension in humans is rare
Keywords: Cerebrospinal fluid pressure, cerebrospinal space, subarachnoid space, Cerebrovascular autoregulation, Headache
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