Effects of oxytocin and anaesthesia on vascular tone in pregnant women: a randomised double-blind placebo-controlled study using non-invasive pulse wave analysis

BMC Pregnancy and Childbirth

Sofus Rabow¹  Sofia Schönbeck²  Ull Hjorth²  Per Olofsson² 

[1]Department of Clinical Sciences Lund, Anaesthesiology and Intensive Care, Skåne University Hospital, Lund University

[2]Department of Clinical Sciences Malmö, Obstetrics and Gynaecology, Skåne University Hospital, Lund University

关键词: Anaesthesia;    Arterial stiffness;    Oxytocin;    Photoplethysmography;    Placebo;    Pregnancy;   

DOI  :  10.1186/s12884-018-2029-1

来源: DOAJ

【 摘 要 】

Abstract Background Oxytocin is an uterotonic drug with profound cardiovascular effects, which in compromised patients could lead to serious events. The objective was to investigate whether oxytocin affects cardiac function and vascular tone in large and small arteries. We hypothesized that oxytocin decreases arterial vascular tone and elevates cardiac output. Methods 51 pregnant women were randomised to treatment with 8.3 μg (5 U) oxytocin or placebo injection during first trimester surgical evacuation of the gravid uterus under general anaesthesia. Oxytocin or placebo was administered once either early or late in the procedure, in a double-blind fashion. Digital photoplethysmography pulse wave analysis variables, heart rate, mean arterial blood pressure and electrocardiographic ST index were recorded before and after anaesthesia and after each injection. Non-parametric statistics were used with a two-sided P value < 0.05 considered significant. Results Anaesthesia induced a significant fall in blood pressure, heart rate and vascular tone in small and peripheral arteries. Oxytocin had a vasodilatory effect on small and peripheral arteries and increased the left cardiac ventricular ejection time. The ST index decreased. Conclusions Pulse wave analysis indicated peripheral vasodilation and increased cardiac output after oxytocin, implying increased myocardial oxygen demand. These effects might have been enhanced by the vasodilating effects of anaesthesia. Previous studies have demonstrated myocardial ischaemia after oxytocin, as reflected by a decrease in ST index in the present study. Trial registration Trial registration number ISRCTN17860978, 2018/03/14, Retrospectively registered.

【 授权许可】

Unknown