Significance of intracranial hypertension in severe head injury

Measurements of intracranial pressure (ICP) were begun within hours of injury in 160 patients with severe brain trauma, and continued in the intensive care unit. Some degree of increased ICP (greater than 10 mm Hg) was present on admission in most cases (82%), and in all but two of the 62 patients with intracranial mass lesions requiring surgical decompression; ICP was over 20 mm Hg on admission in 44% of cases, and over 40 mm Hg in 10%. In patients with mass lesions only very high ICP (greater than 40 mm Hg) on admission was significantly associated with a poor neurological picture and outcome from injury, while in patients with diffuse brain injury any increase in ICP above 10 mm Hg was associated with a poorer neurological status and a worse outcome. Despite intensive measures aimed at prevention of intracranial hypertension, ICP rose over 20 mm Hg during the monitoring period in 64 of the 160 patients (40%). Postoperative increases in ICP over 20 mm Hg (mean) were seen in 52% of the patients who had had intracranial masses evacuated, and could not be controlled by therapy in half of these cases. Even in patients without mass lesions, ICP rose above 20 mm Hg in a third of the cases, despite artificial ventilation and steroid therapy. Of the 48 patients who died, severe intracranial hypertension was the primary cause of death in nearly half and even moderately increased ICP (greater than 20 mm Hg) was associated with higher morbidity in patients with mass lesions and those with diffuse brain injury. Measurement of ICP should be included in management of patients with severe head injury.