A Comparison of Intermittent Intravenous Boluses of Phenylephrine and Norepinephrine to Prevent Spinal-induced Hypotension in Cesarean Deliveries: a Randomized Controlled Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 112
- 试验地点
- 1
- 主要终点
- Bradycardia: Heart rate less than 50 bpm
研究概览
简要总结
Hypotension is a very common complication of spinal anesthesia for cesarean delivery, and can have unwanted side effects on both mother and fetus if not treated promptly. Phenylephrine has been the drug of choice to treat this spinal-induced hypotension. Although phenylephrine is safe to use for this indication, it has been associated with reflex bradycardia and a reduction in cardiac output.
Norepinephrine is a potent vasopressor used to treat hypotension in the critical care setting. Recent studies have looked at norepinephrine's use in the obstetric setting, and have shown that it can be used safely and also has favourable hemodynamic properties when compared to phenylephrine, with less bradycardia and less depression of cardiac output.
The investigators recently conducted a study to determine the ED90 of norepinephrine, and now plan to compare bolus doses of phenylephrine to norepinephrine for treating hypotension following spinal anesthesia for cesarean section.
The investigators hypothesize that norepinephrine, when given as a bolus to prevent post spinal hypotension, will result in around 70% relative decrease in the rate of bradycardia when compared to phenylephrine in patients undergoing elective cesarean delivery under spinal anesthesia.
详细描述
Norepinephrine is a potent vasopressor used to treat hypotension in the critical care setting. Recent studies have looked at norepinephrine's use in the obstetric setting, and have shown that it can be used safely and also has favourable hemodynamic properties when compared to phenylephrine, with less bradycardia and less depression of cardiac output. These studies have been limited to using norepinephrine as an infusion and there is limited data with it being used as a bolus to prevent hypotension. A recent study was undertaken at Mount Sinai hospital to determine the ED90 of norepinephrine to treat post spinal hypotension. Secondary outcome data from this trial showed that the incidence of bradycardia associated with this treatment is approximately 7.5%, several times less when compared to the reported 30% with phenylephrine. It would therefore be prudent at this stage to undertake a randomized trial comparing the hemodynamic profile of phenylephrine (our standard practice) and norepinephrine used as intermittent boluses to prevent hypotension and avoid decrease in heart rate during cesarean delivery.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Informed consent
- •Elective CS under spinal anesthesia
- •Normal singleton pregnancy beyond 36 weeks gestation
- •ASA physical status 2-3
- •Current (pregnant) weight 50-100 kg, height 150-180 cm
- •Age over 18 years
排除标准
- •Patient refusal
- •Inability to communicate in English
- •Allergy or hypersensitivity to phenylephrine
- •Preexisting or pregnancy-induced hypertension
- •Cardiovascular or cerebrovascular disease
- •Fetal abnormalities
- •History of diabetes, excluding gestational diabetes
- •Contra-indications for spinal anesthesia
- •Allergy or hypersensitivity to sulfite
- •Use of monoamine oxidase inhibitors, triptyline or imipramine antidepressants
- •Untreated hyperthyroid patients
研究组 & 干预措施
norepinephrine 6mcg
norepinephrine, given as 1mL IV boluses, to treat post-spinal hypotension
干预措施: Norepinephrine (Drug)
phenylephrine 100mcg
phenylephrine, given as 1mL IV boluses, to treat post-spinal hypotension
干预措施: Phenylephrine (Drug)
结局指标
主要结局
Bradycardia: Heart rate less than 50 bpm
时间窗: 30 minutes
Heart rate less than 50 bpm, from induction of spinal anesthesia
次要结局
- Hypotension: Systolic blood pressure less than 80% of baseline(30 minutes)
- Presence of nausea(30 minutes)
- Number of hypotensive episodes(30 minutes)
- Umbilical artery base excess (mmol/L)(24 hours)
- Hypertension: Systolic blood pressure at or above 120% of baseline(30 minutes)
- Presence of vomiting(30 minutes)
- Umbilical artery partial pressure of carbon dioxide(24 hours)
- Umbilical vein base excess (mmol/L)(24 hours)
- Tachycardia: Heart rate greater than 30% of baseline(30 minutes)
- Number of episodes of nausea(30 minutes)
- Number of episodes of vomiting(30 minutes)
- Total dose of study drug given(30 minutes)
- Umbilical artery partial pressure of oxygen(24 hours)
- Umbilical artery bicarbonate (mmol/L)(24 hours)
- Umbilical vein bicarbonate (mmol/L)(24 hours)
- Apgar scores(1 minute and 5 minutes)
- Umbilical artery pH(24 hours)
- Umbilical vein pH(24 hours)
- Umbilical vein partial pressure of carbon dioxide(24 hours)
- Umbilical vein partial pressure of oxygen(24 hours)