Since 2011, phenylephrine was recommended as the preferred drug to maintain blood pressure in obstetric anesthesia.Phenylephrine, an α adrenoceptor agonist, can induce peripheral vasoconstriction to maintain blood pressure, while reflexly decrease heart rate and result in cardiac output (CO) reduction.Norepinephrine acts not only as an α adrenoceptor receptor agonist, but also as a weaker β adrenergic receptor agonist. It can elevate blood pressure the same asphenylephrine, meanwhile produce positive inotropic effect including increasing heart rate.Thus, the administration of norepinephrine can maintain blood pressue and avoid the decline of CO. The purpose of this study is to evaluate the effect of norepinephrine and phenylephrine on maternal CO in cesarean section by transesophageal echocardiography.
Who can participate
Age range
18 Years – 40 Years
Sex
FEMALE
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. age \>=18 years,\<=40 years;
. height 150-180 cm;
. weight 55-80 kg;
. full-term gestation (\>36 wk and \<41 wk)
. singleton pregnancy undergoing elective cesarean section under CSEA
Exclusion criteria
. contraindications to spinal anesthesia;
. patients with any complicated pregnancy;
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
cardiac output
Timeframe: from baseline (before spinal injection) until 10 minutes after spinal injection