Intracranial pressure in hydrocephalus after subarachnoid haemorrhage

10 patients with hydrocephalus after subarachnoid haemorrhage underwent a continuous ventricular fluid pressure recording for at least 22 hours, 21-67 days after the first subarachnoid haemorrhage. 3 patients had normal pressures; 4 patients had pressures somewhat above normal, between 10 and 20 mmHg; three patients had rather a high pressure, with a mean above 20 mmHg and peaks to 45 mmHg. 5 patients had a shunt operation, which seemed to improve the patient's condition in 3 instances; a sixth patient improved during ventricular drainage, but suffered a fatal haemorrhage before a shunt could be inserted. Of those 3 patients who improved after a shunt, 2 had a ventricular fluid pressure somewhat above normal (see Fig. 2) and one a high pressure. Of the 2 patients that did not improve in spite of a well-functioning shunt, one had a pressure somewhat above normal (Fig. I) and one high pressure (Fig. 3). 4 patients did not have a shunt operation; in 3 of these the pressure appeared to be within normal limits, and one patient, though the pressure was somewhat above normal, was in such a good conditon that no operation was thought necessary. One of the patients with normal pressure has spent 12 months in a mental hospital; the others recovered reasonably well, though only one has returned to work. From this small series it seems that a pressure recording cannot predict how the patient is going to become with a shunt; but the recording may help to sortout those with normal pressure, who are not likely to require a shunt, particularly as many complications are on record for shunts. In 2 instances, an aneurysmo re-bled after a high ventricular fluid pressure had been reduced, 40 and 38 days after the first subarachnoid haemorrhage; the risks inherent in changing the pressure conditions within the skull should be remembered.