Determination of the Minimum Effective Volume of Crystalloid Co-Loading for Preventing Spinal Anesthesia-Induced Hypotension in Cesarean Section: A Biased Coin Design Study
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 45
- 主要终点
- Minimum Effective Volume (MEV90) of Intravenous Crystalloid Co-Loading (mL/kg)
研究概览
简要总结
The goal of this clinical trial is to find the minimum effective volume of IV crystalloid that should be given with phenylephrine to prevent hypotension caused by spinal anesthesia in healthy, term pregnant adults having elective cesarean delivery.
The main questions are:
What is the minimum effective volume (MEV90, mL/kg) of crystalloid co-loading that prevents spinal-anesthesia-induced hypotension in ≥90% of participants?
What maternal side effects and newborn outcomes occur with this strategy (e.g., nausea/vomiting, need for extra vasopressors, total fluids/blood loss, Apgar scores, and umbilical cord blood gases)?
There is no separate comparison group; this is a single-arm, adaptive dose-finding study.
Participants will:
Receive a predefined volume of IV crystalloid over ~10 minutes during spinal anesthesia while phenylephrine is infused. Have blood pressure and symptoms monitored; receive rescue treatment if needed. Allow the next participant's fluid volume to be adjusted based on whether hypotension occurred (biased-coin design). Be followed through postoperative day 2 for maternal and newborn outcomes.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 19 Years 至 —（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Pregnant adults ≥19 years scheduled for elective cesarean delivery under spinal anesthesia
- •Term pregnancy (≥37 weeks' gestation)
排除标准
- •Emergency cesarean delivery
- •Hypertensive disorders of pregnancy (preeclampsia/eclampsia) or hypertension
- •Multiple gestation
- •Body weight <50 kg or BMI >35 kg/m²
- •Renal impairment or eGFR ≤90 mL/min/1.73 m²
- •Heart failure or other heart disease
- •History of bronchial asthma or other pulmonary disease
结局指标
主要结局
Minimum Effective Volume (MEV90) of Intravenous Crystalloid Co-Loading (mL/kg)
时间窗: From intrathecal injection (start of spinal anesthesia) to end of surgery
The smallest crystalloid co-loading dose (mL/kg) that prevents spinal-anesthesia-induced hypotension in ≥90% of participants when given with prophylactic phenylephrine.
次要结局
- Incidence of intraoperative hypotension (mmHg)(From intrathecal injection to end of surgery)
- Incidence of intraoperative hypertension (mmHg)(From intrathecal injection to end of surgery)
- Additional bolus phenylephrine requirement(From intrathecal injection to end of surgery)
- Total Phenylephrine Dose (µg)(From intrathecal injection to end of surgery)
- Estimated blood loss (mL)(From skin incision to end of surgery)
- Incidence of Maternal Nausea Associated With Hypotension(From intrathecal injection to end of surgery)
- Incidence of Maternal Vomiting Associated With Hypotension(From intrathecal injection to end of surgery)
- Incidence of Maternal Dizziness/Lightheadedness Associated With Hypotension(From intrathecal injection to end of surgery)
- Neonatal Apgar score at 1Minute(At 1 minute after birth)
- Neonatal Apgar Score at 5 Minutes(At 5 minutes after birth)
- Umbilical Arterial pH(At delivery (immediately after birth))
- Umbilical Arterial Base Excess (mmol/L)(At delivery (immediately after birth))
- Pulmonary edema(Through postoperative day 2)
- Clinically Significant Generalized Edema(Through postoperative day 2)
- Acute Heart Failure(Through postoperative day 2)