Experimental study of intracisternal administration of tissue-type plasminogen activator followed by cerebrospinal fluid drainage in the ultra-early stage of subarachnoid haemorrhage.

This experimental study evaluated the effect of intrathecal injection of tissue-type plasminogen activator followed by cisternal drainage in the ultra-early stage of aneurysmal subarachnoid haemorrhage to prevent vasospasm. Twenty Japanese white rabbits were divided into five groups. Either tPA (groups A, B, and E) or saline (groups C and D) was injected intrathecally 1 hour (groups A, B, C, and D) or 21 hours (group E) after the intrathecal injection of blood. Cerebrospinal fluid was drained 2, 4, and 6 hours after the intrathecal injection of blood (groups A, C, and E). On day 4, the angiographic caliber of the basilar artery in each group was as follows (mean +/- SD): A, 85.9 +/- 5.0%; B, 74.6 +/- 5.3%; C, 69.1 +/- 2.7%; D, 64.0 +/- 4.9%; E, 80.2 +/- 2.7% (compared with baseline). In the two groups in which CSF was drained (groups A and C), fibrinolysis with tPA significantly suppressed vasospasm. In the two groups treated with tPA (groups A and B), cisternal drainage significantly suppressed vasospasm. In the two groups treated with saline (groups C and D), however, cisternal drainage did not suppress vasospasm. Examination of the series of CSF samples (groups A and C) showed that fibrinolysis with tPA effectively cleared clots early. In the two groups treated with tPA and CSF drainage (groups A and E), early removal of subarachnoid clots reduced the degree of vasospasm. Early fibrinolysis with tPA and early removal of subarachnoid clots by drainage is effective for preventing vasospasm.