Up-Down Determination of the ED90 of Metaraminol to Treat Hypotension During Cesarean Section

Hypotension Clinical Trial

Official title:

Up-Down Determination of the ED90 of Metaraminol to Treat Hypotension During Elective Cesarean Section

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01108874
• Other study ID #: CEP1241/09
• Status: Completed
• Phase: Phase 2
• First received: April 19, 2010
• Last updated: September 30, 2010
• Start date: November 2009
• Est. completion date: August 2010

Study information

• Verified date: September 2010
• Source: Federal University of São Paulo
• Contact: n/a
• Is FDA regulated: No
• Health authority: Brazil: Ethics Committee
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to find the best dose of metaraminol to be used in patients during elective cesarean sections.

Description:

The purpose of this study is to determine the effective dose 90% (ED90) of metaraminol to treat hypotension after spinal anesthesia in elective cesarean sections (CS). It is a double-blind study that uses the biased-coin up-down sequential allocation method to determine the ED90 of metaraminol.

Baseline systolic blood pressure (SBP) will be determined by three automated measures 3 minutes apart just before CS. During the period from induction of spinal anesthesia to fetal delivery SBP will be monitored every minute and metaraminol will be administered every time it is lower than baseline value. If SBP falls below 80% of baseline value, the treatment will be considered a failure. An adequate response will be defined as the absence of hypotension during the study period.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 48
• Est. completion date: August 2010
• Est. primary completion date: August 2010
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Elective CS under spinal anesthesia

• Normal singleton pregnancy beyond 36 weeks gestation

• ASA physical status I/II

• Age over 18 years

Exclusion Criteria:

• Patient refusal

• Allergy to metaraminol

• Preexisting or pregnancy-induced hypertension

• Cardiovascular or cerebrovascular disease

• Fetal abnormalities

Study Design

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

Related Conditions & MeSH terms

• Hypotension

Intervention

Drug:
• Metaraminol
Patients will be given metaraminol every time SBP falls below baseline value.

Locations

Country	Name	City	State
Brazil	Hospital São Paulo	São Paulo

Sponsors (1)

Lead Sponsor	Collaborator
Federal University of São Paulo

Country where clinical trial is conducted

Brazil, 

References & Publications (4)

Ngan Kee WD, Lau TK, Khaw KS, Lee BB. Comparison of metaraminol and ephedrine infusions for maintaining arterial pressure during spinal anesthesia for elective cesarean section. Anesthesiology. 2001 Aug;95(2):307-13. — View Citation

Ngan Kee WD, Lee A. Multivariate analysis of factors associated with umbilical arterial pH and standard base excess after Caesarean section under spinal anaesthesia. Anaesthesia. 2003 Feb;58(2):125-30. — View Citation

Pace NL, Stylianou MP. Advances in and limitations of up-and-down methodology: a précis of clinical use, study design, and dose estimation in anesthesia research. Anesthesiology. 2007 Jul;107(1):144-52. Review. — View Citation

Tanaka M, Balki M, Parkes RK, Carvalho JC. ED95 of phenylephrine to prevent spinal-induced hypotension and/or nausea at elective cesarean delivery. Int J Obstet Anesth. 2009 Apr;18(2):125-30. doi: 10.1016/j.ijoa.2008.09.008. Epub 2009 Jan 21. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	The ED90 of Metaraminol to treat hypotension in elective cesarean section will be determined.	Bolus doses of metaraminol will be used every time SBP falls below baseline values and maternal responses to doses will be used to build a dose response curve from where ED90 will be estimated.	From spinal induction until delivery (on average 30-60min)	No
Secondary	Maternal Demographics (Age, Height, Weight and Gestational Age)			No
Secondary	Incidence of Nausea and Vomiting		From spinal induction until delivery (on average 30-60min)	No
Secondary	Time between skin incision and delivery			No
Secondary	Time between uterine incision and delivery			No
Secondary	Total dose of metaraminol			No
Secondary	Number of Participants with Hypertension or Bradycardia as a Measure of Safety and Tolerability		From spinal induction until delivery (on average 30-60min)	No
Secondary	Umbilical blood gases
Secondary	Fetal well-being with Apgar scores			No