IX. On the changes produced in the circulation and respiration by increase of the intracranial pressure or tension

Abstract

The authors have made for some time the effect of an increase in intracranial pressure or tension the subject of an experimental inquiry, and they have in this paper recorded the results obtained, in so far as the increase of intracranial pressure affects the circulation and respiration. They conclude that the increase in intracranial pressure influences the circulation and respiration through the diminution in the physiological activity of the medulla which it causes, and show that the changes produced by the pressure assume a sequence according to the degree to which the activity of the medulla is impaired.

Intracranial Pressure Monitoring in Perspective

“…As von Bergmann noted in animals the response appears to start as the mean supratentorial pressure approaches diastolic arterial pressure. It is possible to speculate that ischemia of the cer ebral hemispheres (rather than medullary anemia) may trigger the hyperten sive response by removal of the normal supratentorial inhibition of brain stem centers with the resultant release of sympatho mimetic influences lead ing to increased heart rate and marked peripheral vascular response.Although popularized by Cushing the 'Cushing triad' and its possible relationship to medullary anemia had been described earlier by Hill [35] and Spencer and Horsley [82]. The popularity of the Cushing triad as an indicator of intracranial hypertension probably, as Browder and Meyers [4] noted, re flected the need for observable data in the management of the neurosurgical patient.…”