Phenylephrine for Spinal Induced Hypotension - Full Text View

Sponsor:	IWK Health Centre
Information provided by (Responsible Party):	Ronald George, IWK Health Centre
ClinicalTrials.gov Identifier:	NCT00781157

Purpose

This study is designed to determine the ED90 for a single dose of phenylephrine for the treatment of spinal induced hypotension in parturients presenting for an elective CD. The ED90 is the effective dose at which 90% of subjects will have a "positive" response to phenylephrine. The primary outcome measure is the ED90 for bolus phenylephrine. Secondary outcomes include the need for additional vasopressors, glycopyrolate to treat bradycardia, and the presence of hypertension following administration of phenylephrine.

Condition	Intervention	Phase
Hypotension	Drug: Phenylephrine bolus	Phase 4

Study Type:	Interventional
Study Design:	Endpoint Classification: Efficacy Study Intervention Model: Single Group Assignment Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor) Primary Purpose: Treatment
Official Title:	Up-down Determination of the ED90 of Phenylephrine for Spinal Induced Hypotension in Parturients Undergoing Cesarean Delivery

Resource links provided by NLM:

MedlinePlus related topics: Cesarean Section High Blood Pressure Low Blood Pressure

Drug Information available for: Phenylephrine Phenylephrine hydrochloride Oxymetazoline Oxymetazoline hydrochloride

U.S. FDA Resources

Further study details as provided by IWK Health Centre:

Primary Outcome Measures:

The primary outcome measure is the ED90 for bolus phenylephrine. [ Time Frame: Intraoperative ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Secondary outcomes include the need for additional vasopressors, glycopyrolate to treat bradycardia, and the presence of hypertension following administration of phenylephrine. [ Time Frame: Intraoperative ] [ Designated as safety issue: No ]

Estimated Enrollment:	40
Study Start Date:	January 2008
Study Completion Date:	October 2008
Primary Completion Date:	August 2008 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Experimental: 1	Drug: Phenylephrine bolus The initial dose of phenylephrine will be 100 mcg, a dose within the clinical range currently in use at our center. The subsequent dose is based upon the response of the preceding subject in the usual up-and-down method (UDM), which is outlined in the "data analysis" section of the protocol. The dosing changes will be in increments of 20 micrograms. A successful response to this dose will be entered into a spreadsheet, designed by our statistician, which will determine the subsequent dose based upon the UDM. If a failure is observed in the previous subject, the dose is stepped up in the next subject. If a success is observed the next subject is randomized with probability of 0.10 to the next lower dose and with probability 0.90 to the same dose.

Arms

Assigned Interventions

Experimental: 1

Drug: Phenylephrine bolus

The initial dose of phenylephrine will be 100 mcg, a dose within the clinical range currently in use at our center. The subsequent dose is based upon the response of the preceding subject in the usual up-and-down method (UDM), which is outlined in the "data analysis" section of the protocol. The dosing changes will be in increments of 20 micrograms. A successful response to this dose will be entered into a spreadsheet, designed by our statistician, which will determine the subsequent dose based upon the UDM. If a failure is observed in the previous subject, the dose is stepped up in the next subject. If a success is observed the next subject is randomized with probability of 0.10 to the next lower dose and with probability 0.90 to the same dose.

Eligibility

Ages Eligible for Study:	18 Years and older
Genders Eligible for Study:	Female
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Non-emergent cesarean delivery with planned regional anesthesia (i.e. elective planned cesarean delivery for malposition, patient choice, cervical pelvic disproportion, previous cesarean delivery and other diagnosis that require a predetermined cesarean delivery)
American Society of Anesthesia physical status class I & II (ASA I - Healthy, ASA II - mild and controlled systemic disease, eg. controlled essential hypertension)
Age ≥ 18 years (Standard within the obstetrical literature)
Term gestational age
English-speaking

Exclusion Criteria:

Morbid Obesity (Body Mass Index ≥ 45 kg/m2) (Morbidly obese parturients require a dose of local anesthetic less than the standardized dose in this study, typically have an exaggerated response to vasopressors, and the blood pressure cuff occasionally needs to be replaced by an intraarterial catheter due to limitations in size)
Height < 5'0" (Women < 5'0" are likely to require a dose of local anesthetic less than the standardized dose in this study)
Laboring women
Urgent or emergency cesarean delivery
Severe hypertensive disease of pregnancy defined as systolic blood pressure (SBP) > 160mmHg, diastolic blood pressure (DBP) > 110mmHg and/or requiring antihypertensive treatment or associated with significant proteinuria
Severe maternal cardiac disease
Diabetes type I
Subjects on monoamine oxidase inhibitors (MAOI's) or tricyclic antidepressants
Fetal anomalies
Failed spinal anesthesia
Subject enrollment in another study involving a study medication within 30 days of CD
Any other physical or psychiatric condition which may impair their ability to cooperate with study data collection

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00781157

Locations

Canada, Nova Scotia
IWK Health Centre
Halifax, Nova Scotia, Canada, B3K 6R8

Sponsors and Collaborators

IWK Health Centre

Investigators

Principal Investigator:

Ronald B George, MD FRCPC

IWK Health Centre

More Information

No publications provided

Responsible Party:	Ronald George, Primary Investigator, MD, FRCPC, Assistant Professor, IWK Health Centre
ClinicalTrials.gov Identifier:	NCT00781157 History of Changes
Other Study ID Numbers:	IWK-4061-2007, IWK REB 4061
Study First Received:	October 27, 2008
Last Updated:	November 1, 2011
Health Authority:	Canada: Health Canada

Keywords provided by IWK Health Centre:

Spinal induced hypotension in cesarean delivery

Additional relevant MeSH terms:

Hypotension
Vascular Diseases
Cardiovascular Diseases
Phenylephrine
Oxymetazoline
Adrenergic alpha-1 Receptor Agonists
Adrenergic alpha-Agonists
Adrenergic Agonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions

Physiological Effects of Drugs
Cardiotonic Agents
Cardiovascular Agents
Therapeutic Uses
Mydriatics
Autonomic Agents
Peripheral Nervous System Agents
Sympathomimetics
Vasoconstrictor Agents
Nasal Decongestants
Respiratory System Agents
Protective Agents

ClinicalTrials.gov processed this record on May 23, 2012