Norepinephrine vs. Phenylephrine for Spinal Hypotension in Cesarean Section

Universitas Sumatera Utara46 enrolled

Overview

This clinical trial was conducted to compare the effectiveness and safety of two medications-norepinephrine and phenylephrine-in treating low blood pressure (hypotension) that often occurs during spinal anesthesia for cesarean section (C-section) deliveries. Spinal anesthesia is commonly used during C-sections but can cause a drop in the mother's blood pressure, which may affect both the mother and the baby. In this study, 46 pregnant women undergoing elective C-sections were randomly given either norepinephrine (4 mcg) or phenylephrine (50 mcg) when their blood pressure dropped. Researchers monitored their heart rate, blood pressure, and any side effects for 30 minutes after anesthesia. The results showed that both drugs were effective in raising blood pressure. However, norepinephrine kept the heart rate more stable, while phenylephrine caused a noticeable slowing of the heart rate (bradycardia). Both drugs were safe and well tolerated. This study suggests that norepinephrine may be a better option for managing low blood pressure during spinal anesthesia in C-sections, especially when maintaining heart rate and cardiac output is important.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

QUADRUPLE

Enrollment

Conditions

Hypotenstion Cesarean Resection

Interventions

Norepinephrine 4mcgDRUG

Norepinephrine 4 mcg IV bolus diluted in 2 mL normal saline, administered upon onset of hypotension during spinal anesthesia.

Phenylephrine 50 mcgDRUG

Phenylephrine 50 mcg IV bolus diluted in 2 mL normal saline, administered upon onset of hypotension during spinal anesthesia.

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Female patients aged 18-40 years * Undergoing elective cesarean section * Receiving spinal anesthesia * Classified as ASA Physical Status II * Stable baseline hemodynamics prior to anesthesia * Not using inotropic, chronotropic, or vasoactive drugs before surgery Exclusion Criteria: * Emergency cesarean section * Fetal distress * Preeclampsia or eclampsia * Contraindications to spinal anesthesia (e.g., coagulopathy, infection at injection site) * Known allergy to norepinephrine or phenylephrine * Hemodynamic instability prior to vasopressor administration * Withdrawal from study or refusal to participate * Failure to develop post-spinal hypotension

Outcomes

Primary Outcomes

Change in Systolic Blood Pressure (SBP) After Vasopressor Administration

Change in systolic blood pressure measured before vasopressor administration (T0-T1) and two minutes after administration (T2) in response to intravenous bolus of norepinephrine 4 mcg or phenylephrine 50 mcg during spinal anesthesia-induced hypotension in cesarean section patients.

Time frame: Baseline to 2 minutes post-administration (T0-T2)