Thirty-five patients with symptomatic vasospasm (SV) following aneurysmal subarachnoid hemorrhage (SAH) were managed according to a method based on hemodynamic manipulation, monitored by Swan-Ganz catheter. Nine out of these had delayed surgery. For those who developed SV, the pulmonary wedge pressure (Pcwp) and/or central venous pressure (CVP) were immediately increased up to the point at which neurological deficit was reversed by rapid injection of fresh frozen plasma, albuminates, low molecular dextrose, and glycerol. On this regimen, patients were closely observed for any neurological change. Then the hemodynamic parameters were maintained as optimal values until they could be reduced below optimal values without reappearance of neurological deficit. In inoperable patients, special attention was given in making a decision about discontinuing the regimen. The results were compared with thirty-seven patients with SV who were treated with conventional hypervolemic therapy (CHT) by continuous administration of albuminates. In the treatment of CHT, optimal values could hardly be established, so the same hemodynamic parameters were applied in all the cases. From this study, in the majority of the cases optimal values were found as follows: Pcwp up to 10-15 mmHg, and CVP below 11 cmH2O. On the contrary, in 20% of patients, neurological deficit was reversed by increasing CVP to a point not above 7 cmH2O. Correlation between neurological reversal and systemic blood pressure was not statistically significant. After this regimen (OHT), 74% of patients showed immediate improvement after volume expansion, and, in 80%, outcome was good, while 20% died. The motor function at the time of discharge was more than 3 on the manual test in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)