The effect of increased intracranical pressure on pulse wave (author's transl)

Abstract

It is well known that the intracranial pulse wave amplitude increases with rising intracranial pressure (ICP). However, little is known about how the form of the pulse wave changes with variation in ICP. One or two peaks were observed in the descending slope of the pulse wave, synchronous with the heart beat in dogs. As ICP increased, the amplitude as well as the peak of the pulse wave became more prominent and the shape finally became monotonous. These changes can be used as a diagnostic tool to assess the intracranial volume-pressure relationships. In dogs where the vasotonicity was strengthened by a hypertensive drug (noradrenalin), alteration of the pulse wave occurred with ICP elevation. However, when the systemic blood pressure was elevated by inflation of an aortic balloon, ICP elevation resulted in the monotonous form of the pulse wave. On the contrary, when the vasotonicity was weakened by a hypotensive drug (regitine), the form of the pulse wave became monotonous. However, exsanguination did not change the form of the wave under ICP elevation. These results suggest that the cerebrovascular tone contributes to the form of the pulse wave under increased ICP.