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

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

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

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

Detailed Summary:

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.


Sponsor: Federal University of São Paulo

Current Primary Outcome: 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) ]

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.


Original Primary Outcome: Same as current

Current Secondary Outcome:

  • Maternal Demographics (Age, Height, Weight and Gestational Age)
  • Incidence of Nausea and Vomiting [ Time Frame: From spinal induction until delivery (on average 30-60min) ]
  • Time between skin incision and delivery
  • Time between uterine incision and delivery
  • Total dose of metaraminol
  • 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) ]
  • Umbilical blood gases
  • Fetal well-being with Apgar scores


Original Secondary Outcome: Same as current

Information By: Federal University of São Paulo

Dates:
Date Received: April 19, 2010
Date Started: November 2009
Date Completion:
Last Updated: September 30, 2010
Last Verified: September 2010