[Use of prostacyclin in patients with ischemic stroke. A double-blind method II]. Double-blind controlled trial of the therapeutic effects of prostacyclin in patients with completed ischaemic stroke. Double-blind controlled trial of prostacyclin in cerebral infarction.
Thirty patients with acute ischaemic stroke were allocated randomly into a group treated with prostacyclin and a group receiving placebo. The treatment was started 24 to 72 hours after the onset of stroke. Prostacyclin sodium (Wellcome, U.K. or Chinoin, HPR) or its solvent (glycine buffer) were administered intravenously once daily during 2 weeks in 6-hour infusions. Prostacyclin was infused at rates of 2.5-5.0 ng/kg/min. Statistically significant improvement appeared from the second day on in the prostacyclin group, and only from the eighth day on in the placebo group. However, the final improvement was not statistically different between these groups. In a pilot study, 26 patients with acute completed strokes (48 hours to 5 days after cerebral infarction) were randomly assigned to the prostacyclin (PGI2) or placebo groups. PGI2 sodium salt (Epoprostenol, Wellcome Research Laboratories and Upjohn Company) or its solvent (glycine buffer) were infused into the subclavian vein for six-hour periods in five courses separated by six-hour intervals. Prostacyclin was administered at a rate of 2.5-5.0 ng/kg/min. A significant alleviation of neurological deficits occurred 6 and 54 hours after the treatment in patients receiving prostacyclin. This improvement lost its statistical significance at the end of a two-week observation period. It is concluded that further modified controlled studies are required to evaluate the therapeutic usefulness of PGI2 in the treatment of patients with cerebral ischaemia. Thirty-two patients with acute cerebral infarction received either prostacyclin or placebo intermittently for 65 hours. Pulse and blood pressure were not altered by prostacyclin. After infusion there was no change in infarct volume or cerebral blood flow in either group. After normalisation for starting values, age and site of cerebral infarction there was a greater than 10% improvement in speech in the prostacyclin group, but minimal changes in neurological score or disability status. Age is related to neurological score at 14 days after stroke by decreasing improvement by 6.8% for each additional 10 years. This study has not been able to demonstrate that prostacyclin is effective in the treatment of ischaemic stroke, but due to the sample size the chance of proving this statistically (the power) was small. Similarly any conclusion that prostacyclin is not effective may be wrong because of the Type II error probability being high.
Too few patients have been studied in randomised trials to allow conclusions to be drawn about the effect of prostacyclin treatment on survival of people with acute stroke.