[Effect of subpartal tocolysis on maternal cardiovascular parameters with subsequent cesarean section in general...

The influence of subpartal beta-sympathicomimetic tocolysis on a subsequent Caesarean section with halothane as inhalational anaesthetic was examined in 42 pregnant women. Alterations in the heart rate, blood pressure and heart action during the operation were measured. 23 patients (group "bolus") received fenoterol monotherapy. In 19 patients (group "iv-tocolysis") fenoterol was combined with the cardioselective beta-1-blocking agent metoprolol. In comparison with these two groups, 25 pregnant women without tocolysis were examined as controls. There were only slight differences in heart rate and blood pressure between the three groups. Arrhythmias were registered in 42 percent of the cases, in most cases during light anaesthesia before delivery. Sinus tachycardias with a heart rate of 130 beats per minute or more were observed most frequently. Arrhythmias of ectopic origin and sinus bradycardias, however, were found seldom. The incidence of arrhythmias in the three groups during Caesarean section did not differ significantly. There was no evidence for an increased occurrence of arrhythmias following beta-sympathicomimetic tocolysis.