SINGLE INTRACISTERNAL BOLUS OF RECOMBINANT TISSUE PLASMINOGEN-ACTIVATOR IN PATIENTS WITH ANEURYSMAL SUBARACHNOID HEMORRHAGE - PRELIMINARY ASSESSMENT OF EFFICACY AND SAFETY IN AN OPEN CLINICAL-STUDY

Intracisternal thrombolysis with recombinant tissue plasminogen activator (rtPA) was performed in 20 patients with aneurysmal subarachnoid hemorrhage. All patients had blood accumulations in the basal cisterns according to Fisher's Grade III, thus being at a high risk for the development of posthemorrhagic delayed ischemic deficits (DID). All patients underwent an operation within 72 hours after aneurysm rupture. After the aneurysm had been excluded from the cerebral circulation, a single bolus of 10 mg of rtPA was injected into the basal cisterns. Postoperatively, serial computed tomographic examinations demonstrated radical blood clot removal in all patients. Daily transcranial Doppler examinations revealed accelerated blood flow velocities in 16 of 20 patients. The postoperative results according to the Glasgow Outcome Scale were as follows: 16 patients were Grades I and II, 2 patients were Grade III. Two patients died postoperatively, 1 because of a bowel perforation, and 1 from DID attributable to the development of a cerebral vasospasm. No postoperative bleeding complications occurred. It is concluded that pharmacological removal of subarachnoid blood accumulations can be achieved in a safe and effective way by an intrathecal single bolus of 10 mg of rtPA instilled into the basal cisterns after aneurysm clipping. The acceleration of blood flow velocities in a number of patients indicated that posthemorrhagic arterial narrowing was not completely prevented by this treatment, but this remained asymptomatic in 19 of 20 patients. Although extensive blood clot removal can be achieved by a single bolus of rtPA, more radical or complete blood removal probably requires the use of higher drug concentrations or additional postoperative intracisternal or intraventricular rtPA injections, for which further studies are needed. Although the occurrence of cerebral vasospasm and DID was not completely prevented by rtPA application, the low incidence of DID in a group of patients with a high probability of perioperative vasospasm resulting from high intracisternal blood volumes is promising.