WE HAVE previously reported that changes in cerebral blood flow may have a profound effect in the same direction on the cerebrospinal fluid pressure of rhesus monkeys.1 The present communication deals with this relationship in man.
MATERIAL AND METHODS
The types of patients studied and the methods of continuously recording the several pressures of interest have been described.2 Included in this study are patients who were sufficiently cooperative to hyperventilate and lie quietly.
The administration of carbon dioxide in air increases the cerebral blood flow3 and the cerebrospinal fluid pressure.4 Hyperventilation decreases the flow5 and the fluid pressure.4 The cerebrospinal fluid pulse pressure varies concomitantly with the irregular arterial pulses of auricular fibrillation and extrasystoles. These procedures and conditions usually cause concomitant changes in the arterial pressure in the same direction, which have been assumed by other investigators to be the causative mechanism,