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Preventive Intramuscular Phenylephrine in Elective Cesarean Section Under Spinal Anesthesia

Preventive Intramuscular Phenylephrine in Elective Cesarean Section Under Spinal Anesthesia: A Randomized Controlled Tiral

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03507387
Enrollment
99
Registered
2018-04-25
Start date
2018-04-01
Completion date
2018-08-31
Last updated
2019-07-05

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Elective Cesarean Section, Spinal Anesthesia

Keywords

Intramuscular, Phenylephrine

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.

Interventions

DRUGPhenylephrine

5 mg (1ml) phenylephrine 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 .

DRUGNormal saline

1ml 0.9% normal saline intramuscular injection will be given into the gluteus maximus muscle before anesthesia and after the subarachnoid injection is completed.

DRUGBupivacaine

All patients will receive spinal anesthesia with bupivacaine.

Sponsors

Xuzhou Medical University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
FEMALE
Age
18 Years to 40 Years
Healthy volunteers
No

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.

Design outcomes

Primary

MeasureTime frameDescription
Umbilical artery potential of hydrogen (pH)after the baby is delivereddetected by a blood gase analyzer

Secondary

MeasureTime frameDescription
Umbilical artery base excessafter the baby is delivereddetected by a blood gase analyzer
Umbilical venous base excessafter the baby is delivereddetected by a blood gase analyzer
Umbilical artery partial pressure of oxygen (PaO2)after the baby is delivereddetected by a blood gase analyzer
Umbilical venous partial pressure of oxygen (PaO2)after the baby is delivereddetected by a blood gase analyzer
Umbilical artery partial pressure of carbon dioxide (PaCO2)after the baby is delivereddetected by a blood gase analyzer
Umbilical venous partial pressure of carbon dioxide (PaCO2)after the baby is delivereddetected by a blood gase analyzer
Umbilical artery lactateafter the baby is delivereddetected by a blood gase analyzer
Umbilical venous potential of hydrogen (pH)after the baby is delivereddetected by a blood gase analyzer
Umbilical artery glucoseafter the baby is delivereddetected by a blood gase analyzer
Umbilical venous glucoseafter the baby is delivereddetected by a blood gase analyzer
Incidence of fetal acidosisafter the baby is deliveredUmbilical artery pH value\<7.20
Incidence of hypotensionintraoperativedecrease of systolic blood pressure\>20% baseline values
Incidence of hypertensionintraoperativeincrease of systolic blood pressure\>20% baseline values
Incidence of bradycardiaintraoperativeheart rate \<50 bpm
Incidence of nausea or vomitintraoperativeobserved by the anesthesiologist
Umbilical venous lactateafter the baby is delivereddetected by a blood gase analyzer

Countries

China

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026