Phenylephrine and Noradrenaline for Post Spinal Anesthesia Hypotension

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

Status

Completed

Phases

Phase 2

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT03015857

Enrollment

200

Registered

2017-01-10

Start date

2017-01-31

Completion date

2017-04-30

Last updated

2017-05-03

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Adverse Anesthesia Outcome

Brief summary

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.

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.

Interventions

DRUGphenylephrine

\- phenylephrine; a vasopressor drug given to prevent post spinal hypotension

DRUGNorepinephrine

\- norepinephrine; a vasopressor drug given to prevent post spinal hypotension

DRUGBupivacaine

intrathecal bupivacaine 10 mg will be given in both groups

DRUGFentanyl

intrathecal fentanyl 20 mcg will be given in both groups

DRUGPlacebo (normal saline)

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

NONE

Eligibility

Sex/Gender

FEMALE

Age

18 Years to 35 Years

Healthy volunteers

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

Design outcomes

Primary

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

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

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026