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

This study has been completed.
Information provided by:
Federal University of São Paulo
ClinicalTrials.gov Identifier:
First received: April 19, 2010
Last updated: September 30, 2010
Last verified: September 2010
The purpose of this study is to find the best dose of metaraminol to be used in patients during elective cesarean sections.

Condition Intervention Phase
Drug: Metaraminol
Phase 2

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Up-Down Determination of the ED90 of Metaraminol to Treat Hypotension During Elective Cesarean Section

Resource links provided by NLM:

Further study details as provided by Federal University of São Paulo:

Primary Outcome Measures:
  • The ED90 of Metaraminol to treat hypotension in elective cesarean section will be determined. [ Time Frame: From spinal induction until delivery (on average 30-60min) ] [ Designated as safety issue: No ]
    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.

Secondary Outcome Measures:
  • Maternal Demographics (Age, Height, Weight and Gestational Age) [ Designated as safety issue: No ]
  • Incidence of Nausea and Vomiting [ Time Frame: From spinal induction until delivery (on average 30-60min) ] [ Designated as safety issue: No ]
  • Time between skin incision and delivery [ Designated as safety issue: No ]
  • Time between uterine incision and delivery [ Designated as safety issue: No ]
  • Total dose of metaraminol [ Designated as safety issue: No ]
  • Number of Participants with Hypertension or Bradycardia as a Measure of Safety and Tolerability [ Time Frame: From spinal induction until delivery (on average 30-60min) ] [ Designated as safety issue: No ]
  • Umbilical blood gases
  • Fetal well-being with Apgar scores [ Designated as safety issue: No ]

Estimated Enrollment: 48
Study Start Date: November 2009
Study Completion Date: August 2010
Primary Completion Date: August 2010 (Final data collection date for primary outcome measure)
Intervention Details:
    Drug: Metaraminol
    Patients will be given metaraminol every time SBP falls below baseline value.
Detailed 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.


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

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
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01108874

Hospital São Paulo
São Paulo, Brazil
Sponsors and Collaborators
Federal University of São Paulo
Principal Investigator: Jefferson Clivatti, MD Disciplina de Anestesiologia, UNIFESP
  More Information

Responsible Party: Jefferson Clivatti, MD, Disciplina de Anestesiologia, Universidade Federal de São Paulo
ClinicalTrials.gov Identifier: NCT01108874     History of Changes
Other Study ID Numbers: CEP1241/09 
Study First Received: April 19, 2010
Last Updated: September 30, 2010
Health Authority: Brazil: Ethics Committee

Keywords provided by Federal University of São Paulo:
Cesarean section
Vasoconstrictor Agents
Anesthesia, Obstetrical/adverse effects
Blood Pressure/drug effects

Additional relevant MeSH terms:
Cardiovascular Diseases
Vascular Diseases
Adrenergic Agents
Adrenergic Agonists
Adrenergic alpha-1 Receptor Agonists
Adrenergic alpha-Agonists
Autonomic Agents
Cardiovascular Agents
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Peripheral Nervous System Agents
Pharmacologic Actions
Physiological Effects of Drugs
Therapeutic Uses
Vasoconstrictor Agents

ClinicalTrials.gov processed this record on February 04, 2016