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Preventive Intramuscular Phenylephrine in Elective Cesarean Section Under Spinal Anesthesia

Not Applicable
Completed
Conditions
Spinal Anesthesia
Elective Cesarean Section
Interventions
Registration Number
NCT03507387
Lead Sponsor
Xuzhou Medical University
Brief Summary

Spinal anesthesia is the preferred anesthesia method in cesarean section to provide satisfactory analgesia and muscle relaxant with less impact on respiratory system. However, hypotension often occurred due to the block of sympathetic nerve, causing maternal decline of frontal lobe oxygenation, nausea vomit and the decrease of uteroplacental perfusion. Several measures are used to prevent or treat hypotension caused by spinal anesthesia: prehydration, limb compression, left lateral tilt of operation tables or usage of vasopressors. In the past decade, the most recommended vasopressor to prevent or treat hypotension in spinal anesthesia in cesarean section was phenylephrine, an α-adrenergic receptor, maintaining maternal blood pressure and fetal acid-base state. In clinical work, there are two ways to use phenylephrine : intravenous method with less onset time (several seconds and duration (several minutes) and intramuscular method with longer onset time (10-15 minutes) and duration (1 hour). Many trials demonstrated the protective effect of preventive intravenous phenylephrine on maternal hemodynamics and neonatal acid-base status. However, few trials reported the effect of preventive intramuscular phenylephrine on cesarean section under spinal anesthesia.

Detailed Description

Hypotension often occurred in parturients undergoing cesarean section in spinal anesthesia. This study aims to determine whether preventive intramuscular phenylephrine can better the fetal acid-base state and maternal hemodynamics.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
99
Inclusion Criteria
  1. Age 18 years to 40 years.
  2. Elective cesarean section
  3. American Society of Anesthesiologists (ASA) grade from I to Ⅱ, height from 150 cm to 180 cm, BMI<40kg/m2
  4. Singleton pregnancy
  5. Without pregnancy complications
Exclusion Criteria
  1. Multiple pregnancy
  2. Preoperative bradycardia
  3. Coagulation dysfunction
  4. Parturients with hypertension, diabetes, eclampsia and other pregnancy complications.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Intramuscular phenylephrine groupNormal salinePatients in intramuscular phenylephrine group will receive spinal anesthesia with bupivacaine. 5 mg (1ml) phenylephrine intramuscular injection will be given into the gluteus maximus muscle before anesthesia.1ml of 0.9% normal saline intravenous injection will be given after the subarachnoid injection is completed.
Intravenous phenylephrine groupNormal salinePatients in intravenous phenylephrine group will receive spinal anesthesia with bupivacaine. 1ml of 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia.100ug (1ml) phenylephrine intravenous injection will be given after the subarachnoid injection is completed.
Placebo groupNormal salinePatients in intravenous phenylephrine group will receive spinal anesthesia with bupivacaine. 1ml of 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia. 1ml of 0.9% normal saline intravenous injection will be given after the subarachnoid injection is completed.
Intramuscular phenylephrine groupPhenylephrinePatients in intramuscular phenylephrine group will receive spinal anesthesia with bupivacaine. 5 mg (1ml) phenylephrine intramuscular injection will be given into the gluteus maximus muscle before anesthesia.1ml of 0.9% normal saline intravenous injection will be given after the subarachnoid injection is completed.
Intravenous phenylephrine groupPhenylephrinePatients in intravenous phenylephrine group will receive spinal anesthesia with bupivacaine. 1ml of 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia.100ug (1ml) phenylephrine intravenous injection will be given after the subarachnoid injection is completed.
Intramuscular phenylephrine groupBupivacainePatients in intramuscular phenylephrine group will receive spinal anesthesia with bupivacaine. 5 mg (1ml) phenylephrine intramuscular injection will be given into the gluteus maximus muscle before anesthesia.1ml of 0.9% normal saline intravenous injection will be given after the subarachnoid injection is completed.
Placebo groupBupivacainePatients in intravenous phenylephrine group will receive spinal anesthesia with bupivacaine. 1ml of 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia. 1ml of 0.9% normal saline intravenous injection will be given after the subarachnoid injection is completed.
Intravenous phenylephrine groupBupivacainePatients in intravenous phenylephrine group will receive spinal anesthesia with bupivacaine. 1ml of 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia.100ug (1ml) phenylephrine intravenous injection will be given after the subarachnoid injection is completed.
Placebo groupPhenylephrinePatients in intravenous phenylephrine group will receive spinal anesthesia with bupivacaine. 1ml of 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia. 1ml of 0.9% normal saline intravenous injection will be given after the subarachnoid injection is completed.
Primary Outcome Measures
NameTimeMethod
Umbilical artery potential of hydrogen (pH)after the baby is delivered

detected by a blood gase analyzer

Secondary Outcome Measures
NameTimeMethod
Umbilical venous partial pressure of oxygen (PaO2)after the baby is delivered

detected by a blood gase analyzer

Umbilical artery base excessafter the baby is delivered

detected by a blood gase analyzer

Umbilical venous potential of hydrogen (pH)after the baby is delivered

detected by a blood gase analyzer

Umbilical venous base excessafter the baby is delivered

detected by a blood gase analyzer

Umbilical venous lactateafter the baby is delivered

detected by a blood gase analyzer

Umbilical venous glucoseafter the baby is delivered

detected by a blood gase analyzer

Incidence of fetal acidosisafter the baby is delivered

Umbilical artery pH value\<7.20

Umbilical artery partial pressure of carbon dioxide (PaCO2)after the baby is delivered

detected by a blood gase analyzer

Umbilical venous partial pressure of carbon dioxide (PaCO2)after the baby is delivered

detected by a blood gase analyzer

Umbilical artery lactateafter the baby is delivered

detected by a blood gase analyzer

Incidence of hypotensionintraoperative

decrease of systolic blood pressure\>20% baseline values

Umbilical artery partial pressure of oxygen (PaO2)after the baby is delivered

detected by a blood gase analyzer

Incidence of hypertensionintraoperative

increase of systolic blood pressure\>20% baseline values

Incidence of bradycardiaintraoperative

heart rate \<50 bpm

Umbilical artery glucoseafter the baby is delivered

detected by a blood gase analyzer

Incidence of nausea or vomitintraoperative

observed by the anesthesiologist

Trial Locations

Locations (1)

The Affiliated Hospital of Xuzhou Medical University

🇨🇳

Xuzhou, Jiangsu, China

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