Abstract
In order to prevent vasospasm, removal of thick subarachnoid clot is carried out in acute aneurysm surgery. Sufficient prevention, however cannot be achieved with this maneuver only. Therefore, we added two other methods; that is, to dissolve and eliminate the remaining subarachnoid clot with the cisternal irrigation of Urokinase (UK) and to change Oxy-Hb, one of the spasmogenic substances, into something harmless with ascorbic acid (AsA).
Cisternal irrigation therapy with UK and AsA has been applied in ruptured aneurysm cases operated upon in the acute stage since 1984. Preoperative CT scan was all in Group 3 according to Fisher's CT classification and the CT number of the clot was over 60, which suggested a great possibility of vasospasm. The total number of cases was 106. After clipping, the subarachnoid clot was removed and then irrigation tubes were inserted deep in to one or both sylvian fissures (inlet) and into the prechiasmal or prepontine cistern (outlet). Twelve hours after the operation, lactate Ringer's solution with UK and AsA (pH 7.2-7.4, osmotic pressure 280-300 mOsm/Kg) was infused at the rate of 20 to 60ml/hr. The concentration of UK was 60-120IU/ml and that of AsA was 2-4mg/ml. The duration of this therapy was between 4 and 15 days (mean: 9.9 days). Among these 106 cases, symptomatic vasospasm was observed in three cases at the rate of 2.8%. Two of them developed a slight hemiparesis immediately after removal of the irrigation tube, but were discharged with no deficit. One patient had a permanent hemiparesis. During irrigation, one case developed meningitis and slight bleeding occurred in two cases, but they recovered completely.
In order to prove the effectiveness of this therapy, we compared these result of the irrigation group with that of the control group, in which irrigation was not performed. The degree of SAH, age, sex, operation timing, preoperative grade by Hunt and Kosnik and distribution of the site of aneurysm are almost the same as the irrigation group. In the control group, symptomatic vasospasm occurred in 37 cases out of 96 cases at the rate of 38.5%.
Considering the outcome, cisternal irrigation therapy with UK and AsA is effective in preventing symptomatic vasospasm after SAH.
