Norepinephrine Prophylaxis for Postspinal Anesthesia Hypotension in Parturients With Preeclampsia

Study Overview
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Brief Summary
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The purpose of this study is to investigate the efficacy and safety of norepinephrine for prophylaxis against postspinal anesthesia hypotension in parturients with preeclampsia undergoing cesarean section.

Detailed Description
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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. As a potential substitute drug for phenylephrine and ephedrine, norepinephrine has gained traction for use in parturients undergoing cesarean section. But the efficacy and safety in parturients with preeclampsia is still unknown. The purpose of this study is to investigate the efficacy and safety of norepinephrine for prophylaxis against post-spinal anesthesia hypotension in parturients with preeclampsia undergoing cesarean section.

Official Title
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Norepinephrine Prophylaxis for Postspinal Anesthesia Hypotension in Parturients With Preeclampsia Undergoing Cesarean Section: a Randomized, Controlled Trial

Conditions
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Adverse Effect

Intervention / Treatment
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* Drug: Phenylephrine
* Drug: Norepinephrine


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control group<br>Phenylephrine infusion simultaneous with subarachnoid block | Drug: Phenylephrine<br>* A maintenance dose of phenylephrine (0.625 μg/kg/min) infusion simultaneous with subarachnoid block<br>* Other names: Vasopressors;|
| Experimental: Norepinephrine group<br>Norepinephrine infusion simultaneous with subarachnoid block | Drug: Norepinephrine<br>* A maintenance dose of norepinephrine (0.05 μg/kg/min) infusion simultaneous with subarachnoid block<br>* Other names: Vasopressors;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of bradycardia | Heart rate < 60 beats/min | 1-15 minutes after spinal anesthesia. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall stability of systolic blood pressure control versus baseline | Evaluated by performance error (PE) | 1-15 minutes after spinal anesthesia | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Norepinephrine, Postspinal anesthesia hypotension, Preeclampsia, Cesarean section