Prevention of vasospasm—cisternal irrigation therapy with urokinase and ascorbic acid

Abstract

Object: Cisternal irrigation therapy with urokinase (UK) and ascorbic acid was introduced to prevent symptomatic vasospasm following aneurysmal subarachnoid hemorrhage (SAH). To dissolve and wash out the subarachnoid clot, cisternal irrigation with urokinase is used. Ascorbic acid is added to degenerate oxy-hemoglobin (Oxy-Hb), one of the strongest spasmogenic substances, into verdoheme-like products which are nonspasmogenic. The efficacy and safety of this therapy were evaluated. Methods: This therapy was performed consecutively in 232 patients. The degree of SAH of the patients was classified as Fisher CT group 3, and the highest CT number (Hounsfield number) exceeded 60 in the SAH, which suggested a significant risk for symptomatic vasospasm. All patients underwent surgery within 72 h from the onset of SAH. After clipping the aneurysm, irrigation tubes were placed in the Sylvian fissure (inlet) unilaterally or bilaterally and in the prepontine or chiasmal cistern (outlet). Lactated Ringer's solution with urokinase (120 IU/ml) and ascorbic acid (4 mg/ml) was infused at a rate of 30 ml/h/side for approximately 10 days. Results: Of the 232 patients studied, symptomatic vasospasm was observed in 7 cases (3.0%), and 3 of these 7 cases (1.3%) demonstrated sequela. The average total blood volume calculated from the drainage fluid was approximately 112 ml. Analysis of the absorption spectrum of the drainage fluid revealed disappearance of the oxy-hemoglobin-specific 576-nm peak. Complications occurred in eight patients during irrigation therapy: two patients experienced seizures, two patients developed meningitis, and four patients had an intracranial hemorrhage. However, all of these patients recovered without neurological deficits. Conclusions: These results suggest that cisternal irrigation therapy with urokinase and ascorbic acid is effective in preventing symptomatic vasospasm following aneurysmal SAH. Although patients are forced to be bedridden for almost 10 days and the medical staffs also are required to exhibit the greatest energy and care during this therapy, the benefit from cisternal irrigation therapy appears to far exceed its disadvantages.