Phenylephrine and Noradrenaline for Post Spinal Anesthesia Hypotension

A Comparison Between Phenylephrine and Norepinephrine Boluses in Prevention of Post-spinal Hypotension During Cesarean Delivery

Hypotension following spinal anesthesia for cesarean section is a serious problem. In this study we investigated the effect of the vasopressors phenylephrine and noradrenaline on postspinal hypotension.

Study Overview

• Status: Completed
• Conditions: Adverse Anesthesia Outcome
• Intervention / Treatment: Drug: Placebo (normal saline); Drug: phenylephrine; Drug: Bupivacaine; Drug: Fentanyl; Drug: Norepinephrine

Detailed Description

On arrival to the operating room, an 18g cannula will be inserted and monitors will be applied (electrocardiography - pulse oximetry - non-invasive blood pressure monitor). Patients will receive spinal anesthesia with 500 ml rapid crystalloid co-load. Ten milligrams heavy bupivacaine in addition to 20 mcg fentanyl will be injected in L3-L4 or L4-L5 interspace using 25 g spinal needle in the sitting position.

After spinal block, patients will be randomly allocated into one of two groups:

• Phenylephrine group (n=100)
• Norepinephrine group (n=100)

Patients who shows SBP above 140 mmHg or heart rate below 55 bpm after the first vasopressor dose will not receive the infusion. The infusion will stop if the SBP was above 140 mmHg or if the heart rate was below 55 bpm. Patients will be positioned in the supine position with left lateral tilt. Block success will be assessed using pinprick, patients with failed block will be excluded from the study. The highest sensory block level will be assessed after 5 minutes from intrathecal injection. Co-hydration will be continued till maximum of 1.5 litres.

• Study Type: Interventional
• Enrollment (Actual): 200
• Phase: Phase 2

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 35 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• full term singleton parturients
• elective cesarean sections

Exclusion Criteria:

• cardiac morbidities
• hypertensive disorders of pregnancy
• peripartum bleeding
• body mass index > 35 will be excluded from the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: phenylephrine,; - Phenylephrine group (n=100): will receive 100 mcg phenylephrine as a single bolus just after intrathecal injection of 10 mg bupivacaine plus 20 mcg fentanyl. The dose will be diluted in 5 mL and given over seconds. A continuous infusion with placebo (normal saline) will start after the first bolus.	Drug: Placebo (normal saline); Drug: phenylephrine; - phenylephrine; a vasopressor drug given to prevent post spinal hypotension; Drug: Bupivacaine; intrathecal bupivacaine 10 mg will be given in both groups; Drug: Fentanyl; intrathecal fentanyl 20 mcg will be given in both groups
Active Comparator: norepinephrine; - Norepinephrine group (n=100): will receive bolus of norepinephrine (10 mcg) directly after spinal block using 10 mg bupivacaine plus 20 mcg fentantanyl followed by continuous infusion of norepinephrine with a rate of 0.1 mcg/kg/min till delivery of the fetus.	Drug: Bupivacaine; intrathecal bupivacaine 10 mg will be given in both groups; Drug: Fentanyl; intrathecal fentanyl 20 mcg will be given in both groups; Drug: Norepinephrine; - norepinephrine; a vasopressor drug given to prevent post spinal hypotension

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Incidence of post spinal hypotension (PSH) defined as percentage of patients with decreased systolic blood pressure less than 80% of the baseline reading during the period from intrathecal injection to delivery of the fetus)	2 hours

Secondary Outcome Measures

Outcome Measure	Time Frame
systolic and diastolic blood pressures measured in mm Hg	2 hours
heart rate measured in beats per minute	2 hours
nausea and vomiting measured in number of attacks	2 hours

Collaborators and Investigators

• Sponsor: Kasr El Aini Hospital
• Investigators: Study Chair: Shereen Refaat, M.D., Lecturer of anesthesia Faculty of medicine Cairo university; Study Chair: Tamer M Rook, M.D., Lecturer of anesthesia Faculty of medicine Cairo university

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2017
• Primary Completion (Actual): March 1, 2017
• Study Completion (Actual): April 1, 2017

Study Registration Dates

• First Submitted: December 5, 2016
• First Submitted That Met QC Criteria: January 7, 2017
• First Posted (Estimate): January 10, 2017

Study Record Updates

• Last Update Posted (Actual): May 3, 2017
• Last Update Submitted That Met QC Criteria: May 1, 2017
• Last Verified: May 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension; Physiological Effects of Drugs; Adrenergic Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Central Nervous System Depressants; Autonomic Agents; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anesthetics, Intravenous; Anesthetics, General; Anesthetics; Protective Agents; Adrenergic alpha-Agonists; Adrenergic Agonists; Cardiotonic Agents; Analgesics, Opioid; Narcotics; Adjuvants, Anesthesia; Anesthetics, Local; Respiratory System Agents; Sympathomimetics; Vasoconstrictor Agents; Mydriatics; Nasal Decongestants; Adrenergic alpha-1 Receptor Agonists; Fentanyl; Bupivacaine; Norepinephrine; Phenylephrine; Oxymetazoline
• Other Study ID Numbers: cesarean sections

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided