Clinical trial NCT04576663: Phenylephrine Prophylaxis for Postspinal Anesthesia Hypotension in Parturients With Preeclampsia
Official title: Phenylephrine Prophylaxis for Postspinal Anesthesia Hypotension in Parturients With Preeclampsia Undergoing Cesarean Section: a Randomized, Placebo-controlled Dose-finding Trial
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Adverse Effect
Keywords: Phenylephrine
Postspinal anesthesia hypotension
Preeclampsia
Cesarean section
Dose-finding
Lead sponsor: General Hospital of Ningxia Medical University
Sponsor class: OTHER
First posted: 2020-10-06
Enrollment: 95
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to investigate the suitable infusion dose of phenylephrine for prophylaxis against postspinal anesthesia hypotension in parturients with preeclampsia undergoing cesarean section.

Detailed description: Preeclampsia, which affects 5% to 7% of parturients, is a significant cause of maternal and neonatal morbidity and mortality. Because of constricted myometrial spiral arteries with exaggerated vasomotor responsiveness, though blood pressure in parturients with preeclampsia are apparently higher than healthy parturients, placental hypoperfusion is more common. Spinal anesthesia is still the preferred mode of anesthesia in parturients with preeclampsia for cesarean section. In preeclampsia parturients, spinal anesthesia improve intervillous blood flow (provided that hypotension is avoided) which contribute to increase placental perfusion. Even so, 17-26% parturients with preeclampsia experienced postspinal anesthesia hypotension due to the extensive sympathetic block that occurred with spinal anesthesia. Practical guidelines for obstetric anesthesia from the American Society of Anesthesiologists and an international consensus statement on the management of hypotension with vasopressors indicate either IV ephedrine or phenylephrine may be used to correct hypotension. But the suitable infusion dose of phenylephrine in parturients with preeclampsia is still unknown. The purpose of this study is to investigate the suitable infusion dose of phenylephrine for prophylaxis against post-spinal anesthesia hypotension in parturients with preeclampsia undergoing cesarean section.

Eligibility criteria: Inclusion Criteria:

* 18-45 years
* Primipara or multipara
* Singleton pregnancy ≥32 weeks
* American Society of Anesthesiologists physical status classification II to III
* Scheduled for cesarean section under spinal anesthesia

Exclusion Criteria:

* Baseline blood pressure ≥180 mmHg
* Body height \< 150 cm
* Body weight \> 100 kg or body mass index (BMI) ≥ 40 kg/m2
* Eclampsia or chronic hypertension
* Hemoglobin \< 7g/dl
* Fetal distress, or known fetal developmental anomaly

Primary outcomes:
measure: The incidence of post-spinal anesthesia hypotension
timeFrame: 1-15 minutes after spinal anesthesia
Secondary outcomes:
measure: Overall stability of systolic blood pressure control versus baseline
timeFrame: 1-15 minutes after spinal anesthesia
measure: Overall stability of heart rate control versus baseline
timeFrame: 1-15 minutes after spinal anesthesia
measure: The incidence of severe post-spinal anesthesia hypotension
timeFrame: 1-15 minutes after spinal anesthesia
measure: The incidence of nausea and vomiting
timeFrame: 1-15 minutes after spinal anesthesia
measure: The incidence of bradycardia
timeFrame: 1-15 minutes after spinal anesthesia
measure: The incidence of hypertension.
timeFrame: 1-15 minutes after spinal anesthesia
measure: pH
timeFrame: Immediately after delivery
measure: Partial pressure of oxygen
timeFrame: Immediately after delivery
measure: Base excess
timeFrame: Immediately after delivery
measure: APGAR score
timeFrame: 1 min after delivery
measure: APGAR score
timeFrame: 5 min after delivery
Other outcomes:
Locations:
Study officials:
affiliation: Hospital of Ningxia Medical University
name: Xinli Ni, Dr.
role: STUDY_CHAIR
References: