Background: Brain stem herniation due to raised intracranial pressure (ICP) is a common cause of mortality in severe bacterial meningitis, but continuous measurements of ICP and the effects of ICP-reducing therapy in these patients have, to our knowledge, not been described. Methods: During a four-year period, an ICP-monitoring device was implanted in patients admitted to our hospital with severe bacterial meningitis and suspected intracranial hypertension. ICP above 20 mmHg was treated using the Lund Concept, which includes antihypertensive therapy (b 1 -antagonist,a 2 -agonist), normalization of the plasma colloid osmotic pressure and the blood volume, and antistress therapy. Results: ICP above 20 mmHg was found in all 12 patients studied. It was effectively reduced in all but two patients, who died. Both patients had a low cerebral perfusion pressure (Ͻ10 mmHg), dilated pupils at start of therapy and were beyond recovery. Radiological signs of brain swelling were present in only five patients. Seven patients recovered fully, while mild audiological impairment was observed in two and minor neurological sequelae in one patient. Eight patients showed signs suggesting imminent brain stem herniation before start of ICP-reducing treatment, seven of whom had been subjected to diagnostic lum-