[Hexoprenalin as a tocolytic drug (author's transl)]

Hexoprenalin, a betasympathomimetic drug, was tested with respect to tocolytic effect and cardiovascular side effects. The dosage varied according to the obstetrical situation and the resultant indication for tocolysis. "Long-term tocolysis" in the prophylaxis of premature labour was indicated when more or less rhythmical uterine contractions were present without any effect, as yet, on the cervix. The dosage was 0.075 microgram/min hexoprenalin intravenously as long-term infusion using a motor pump. In a collective of 20 patients in the last trimester of pregnancy the tocolytic effect was satisfactory, the mean rise in fetal heart rate being 2.43% and the mean rise in maternal heart rate 4.13%. Massive tocolysis to inhibit effective premature labour was indicated when rhythmical uterine contractions had already exerted an effect on the cervix. The dosage was 0.33 microgram/min hexoprenalin intravenously in form of a long-term infusion using a motor pump. In a collective of 20 patients in the last trimester of pregnancy the tocolytic effect was satisfactory, the mean rise in maternal heart rate being 33% and the mean rise in fetal heart rate 3%. Acute tocolysis to inhibit labour during parturition was indicated when ominous signs of fetal distress were present, or as premedication before surgical intervention. The dosage was 1.0 microgram/min hexoprenalin as an intravenous bolus over a period of 5 min. In a collective of 10 patients the tocolytic effect was adequate. Evaluation of the rise in maternal and fetal heart rate does not appear to be useful.