Haemodilution in acute stroke: results of the Italian haemodilution trial. Italian Acute Stroke Study Group.

In a multicentre clinical trial 1267 patients with hemispheric stroke of duration 12 h or less and haematocrit of 35% or more were prospectively randomised to either haemodilution (by venesection and replacement of the same volume of dextran 40 in saline solution) or control treatment groups. In the haemodiluted group mean haematocrit declined from 43% to 37% at 48 h and this fall was maintained for seven days. A plain computed tomographic scan was obtained in all but 37 patients. 87% of the strokes were infarcts and 13% were haemorrhages. After six months the numbers of dead or severely disabled patients were equally distributed in the two treatment groups, and this was true also within the ischaemic and haemorrhagic subgroups. Furthermore, haemodilution did not improve outcome either in the group with very recent ischaemic stroke (less than 6 h) or in the subgroup with highest haematocrit (greater than 45%). Thus, moderate haemodilution does not improve the outcome in acute stroke patients.