Comparison of Norepinephrine and Ephedrine on Hypotension After Spinal Anesthesia in Parturients

Study Overview
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Brief Summary
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Incidence of hypotension is high in parturients after spinal anesthesia. Ephedrine could be used to treat hypotension but lead to lower fetal pH as well. This study is to compare the effects of norepinephrine and ephedrine on hypotension in parturients.

Detailed Description
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Spinal anesthesia is an accepted technique in elective cesarean sections. However, hypotension, resulted from sympathectomy is a common problem, especially in pregnant women. Prevention of this complication by sympathomimetic agents is of potential clinical significance. Ephedrine could be used to treat hypotension but lead to lower fetal pH, which may be related to worse fetal outcome.Norepinephrine could improve the hypotension to the same extent as phenylephrine. In this study, we tend to compare the effects of norepinephrine and ephedrine on hypotension in parturients and on fetal acid status.

Official Title
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Comparison of Norepinephrine and Ephedrine on Hypotension After Spinal Anesthesia in Parturients Undergoing Cesarean Section: a Randomized Double Blinded Controlled Study

Conditions
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Hypotension, Obstetrical Complication of Anesthesia, Complications; Cesarean Section

Intervention / Treatment
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* Drug: Norepinephrine
* Drug: Ephedrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for elective cesarean section Exclusion Criteria: Patients with severe pre-eclampsia Patients with contraindications for spinal anesthesia Patients with multiple pregnancy Patients with gestation <38w

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: norepinephrine<br>norepinephrine is injected after spinal anesthesia | Drug: Norepinephrine<br>* norepinephrine injection<br>* Other names: vasoactive agents;|
| Other: ephedrine<br>ephedrine is injected after spinal anesthesia | Drug: Ephedrine<br>* Ephedrine injection<br>* Other names: vasoactive agents;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of hypotension |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| pH value of fetal arterial blood |  | just after clamp of the umbilical cord, usually 1min to 10min after start of the surgery | 
| incidence of nausea and vomiting |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 
| incidence of dizzy |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 
| incidence of chest congestion |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 
| fetal arterial partial pressure of oxygen |  | just after clamp of the umbilical cord, usually 1min to 10min after start of the surgery | 
| arterial base excess of fetal arterial blood |  | just after clamp of the umbilical cord, usually 1min to 10min after start of the surgery | 
| lowest neonatal cerebral oxygen saturation |  | from clamp of the umbilical cord to 10 min later, 10min in total | 
| lactate level of fetal arterial blood |  | just after clamp of the umbilical cord, usually 1min to 10min after start of the surgery | 
| number of rescue vasoactive agent |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 
| incidence of bradycardia |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 
| incidence of dyspnea |  | from immediately after spinal anesthesia to 30min after spinal anesthesia | 
| Apgar scores of the neonates | The Apgar score is a method to quickly summarize the health of newborn children.It is determined by evaluating the newborn baby on five simple criteria(Appearance, Pulse, Grimace, Activity, Respiration) on a scale from zero to two, then summing up the five values thus obtained. The resulting Apgar score ranges from zero to 10. Scores 7 and above are generally normal; 4 to 6, fairly low; and 3 and below are generally regarded as critically low and cause for immediate resuscitative efforts | from clamp of umbilical cord to 1min after clamping | 
| Apgar scores of the neonates | The Apgar score is a method to quickly summarize the health of newborn children.It is determined by evaluating the newborn baby on five simple criteria(Appearance, Pulse, Grimace, Activity, Respiration) on a scale from zero to two, then summing up the five values thus obtained. The resulting Apgar score ranges from zero to 10. Scores 7 and above are generally normal; 4 to 6, fairly low; and 3 and below are generally regarded as critically low and cause for immediate resuscitative efforts | from clamp of umbilical cord to 5min after clamping | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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norepinephrine, ephedrine