P4.01 EFFECTS OF TOCOLYTICAL MEDICATIONS ON THE PERIPHERAL AND CENTRAL HEMODYNAMICS OF HEALTHY FEMALE VOLUNTEERS

Objective: Atosiban and ritodrine are frequently used tocolytics. Only a few studies investigated the hemodynamic effects of atosiban. We therefore aimed to study the central and peripheral hemodynamics of both medications. Methods: Twenty healthy female volunteers (19–41 yrs) were given atosiban (300 μg/min over 2h) and placebo intravenously (IV) in a random crossover design. Eight of them also received ritodrine IV in escalating doses up to 400μg/min over 2h. The hemodynamics were investigated at steady state using blood pressure (BP) at the brachial artery (BA), pulse wave analysis on the common carotid artery and echocardiography for cardiac output (CO). Statistical analysis was done using Friedman and Wilcoxon tests (value of significance at 0.05). Results: Effects on atosiban/placebo on N=20 did not differ from N=8. Parameters Ritodrine (n=8) Atosiban (n=8) Placebo (n=8) p-value$ CI (l/min/m2) 3.15±0.92*# 1.91±0.47 1.75±0.36 0.002 SI (ml/m2) 28.19±6.34*# 32.47±7.07 30.40±4.27 0.325 HR (bpm) 111±20*# 59±10 57±9 0.002 TPRI (mmHg.ml−1.s) 1.53±0.48*# 2.69±0.85 2.93±0.66 0.005 MAP(mmHg) 76±10*# 84±8 82±6