[The harmful effects of beta2-sympathomimetic drugs as uterine relaxants on caesarean section (author's transl)].

Beta2-sympathomimetics are the most powerful inhibitors of uterine contraction used in order to prevent threatening fetal asphyxia. These drugs, however, can cause harmful interactions with anaesthetics during caesarean section. Our patient-material consists of parturients, who were given a beta2-sympathomimetic, ritodrine, immediately before caesarean section performed under combined general anaesthesia. These patients showed significantly more marked tachycardia, hypotonia and abundant haemorrhage during operation as a consequence of poor uterine contractility than did the control group. Rapid variations in the circulation of the mother may also be disadvantageous to the wellfare of the fetus. These side-effects can best be minimized by omitting atropine-premedication and by expanding the blood volume of the mother before caesarean section with adequate infusion of Ringer-type.