Phenylephrine for Spinal Induced Hypotension

Hypotension Clinical Trial

Official title:

Up-down Determination of the ED90 of Phenylephrine for Spinal Induced Hypotension in Parturients Undergoing Cesarean Delivery

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00781157
• Other study ID #: IWK-4061-2007
• Secondary ID: IWK REB 4061
• Status: Completed
• Phase: Phase 4
• First received: October 27, 2008
• Last updated: May 22, 2013
• Start date: January 2008
• Est. completion date: October 2008

Study information

• Verified date: May 2013
• Source: IWK Health Centre
• Contact: n/a
• Is FDA regulated: No
• Health authority: Canada: Health Canada
• Study type: Interventional

Clinical Trial Summary

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 66
• Est. completion date: October 2008
• Est. primary completion date: August 2008
• Accepts healthy volunteers: No
• Gender: Female
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

1. 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)

2. American Society of Anesthesia physical status class I & II (ASA I - Healthy, ASA II

• mild and controlled systemic disease, eg. controlled essential hypertension)

3. Age = 18 years (Standard within the obstetrical literature)

4. Term gestational age

5. English-speaking

Exclusion Criteria:

1. 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)

2. Height < 5'0" (Women < 5'0" are likely to require a dose of local anesthetic less than the standardized dose in this study)

3. Laboring women

4. Urgent or emergency cesarean delivery

5. 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

6. Severe maternal cardiac disease

7. Diabetes type I

8. Subjects on monoamine oxidase inhibitors (MAOI's) or tricyclic antidepressants

9. Fetal anomalies

10. Failed spinal anesthesia

11. Subject enrollment in another study involving a study medication within 30 days of CD

12. Any other physical or psychiatric condition which may impair their ability to cooperate with study data collection

Study Design

Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Hypotension

Intervention

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.

Locations

Country	Name	City	State
Canada	IWK Health Centre	Halifax	Nova Scotia

Sponsors (1)

Lead Sponsor	Collaborator
IWK Health Centre

Country where clinical trial is conducted

Canada, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The primary outcome measure is the ED90 for bolus phenylephrine.		Intraoperative	No
Secondary	Secondary outcomes include the need for additional vasopressors, glycopyrolate to treat bradycardia, and the presence of hypertension following administration of phenylephrine.		Intraoperative	No