Clinical study on reductions of intracranial pressure by therapeutic agents. I. The effects of mannitol through various methods of administration and the rebound phenomenon caused by the agent

Abstract

Since the discovery of intravenous administration of a glucose solution to reduce the cerebrospinal fluid pressure by Weed and McKibben, the treatment of intracranial hypertension with hypertonic solution has been widely used in the neurological field. Javid and Settlage demonstrated the clinical usefulness of intravenous administration of urea have been reported, such as rebound phenomenon, inflammatory reaction of vessels, hemoglobinuria and so on. These side effects are not observed in intravenous administration of mannitol. Therefore, the mannitol solution has been widely used in the management of raised intracranial pressure (ICP). This paper reports on the effect of hypertonic solution of mannitol on raised intracranial pressure by use of the method of epidural pressure recordings of 45 postoperative patients.The diagnoses of the above patients were as follows : 23 cerebral aneurysms, 14 brain tumors, 6 hypertensive intracerebral hemorrhages and 2 cerebral contusions. Two groups were classified by the infusion dosage and the rate of mannitol. Group A: 0.5 g/kg of mannitol infused within 15, 30 and 60 minutes, and group B: 1.0g/kg of mannitol infused within 30, 60 and 90 minutes.Results:1) Over 23% reduction of ICP was observed in every group by the administration of mannitol solution as compared with the average of the initial ICP levels. In group B, the faster the infusion rate was, the lower was the level of raised ICP.2) In every group, the slower the infusion rate of the same dosage of mannitol solution, the longer the reduction time of ICP lasted.3) A rebound phenomenon was found in 12% of all administered cases.It was concluded that the optimal dosage and the rate of mannitol infusion was 0.5g/kg within 60 minutes and/or 1.0g/kg within 60 minutes.