Ideal Dose of Phenylephrine to Treat Low Blood Pressure During Cesarean Section

Sponsor

Samuel Lunenfeld Research Institute, Mount Sinai Hospital (Other)

Overall Status

Completed

CT.gov ID

NCT00379691

Collaborator

(none)

Enrollment

Location

Duration (Months)

12.5

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The purpose of this study is to determine the minimum effective bolus dose of phenylephrine to prevent post-spinal hypotension in Cesarean section in 95 % of our patients. An adequate response will be defined as the absence of hypotension or nausea/vomiting during the period from induction of spinal anesthesia to uterine incision prior to fetal delivery.

Condition or Disease	Intervention/Treatment	Phase
Hypotension Nausea	Drug: phenylephrine	N/A

Detailed Description

The purpose of this study is to determine the minimum effective bolus dose of phenylephrine to prevent post-spinal hypotension in CS in 95 % of our patients. The study will be conducted in a randomized double-blinded fashion. This dose-response study will be conducted as per the up-down sequential allocation method, modified by the Narayana rule, designed to cluster the results around the ED95.

Blood pressure will be monitored every minute from intrathecal injection to the delivery of the child. Phenylephrine will be administered every time the blood pressure is equal to or lower than the control value.Hypotension will be defined as a SBP less than 80 % of the baseline value, in which case the treatment will be a failure. Hypertension will be defined as a SBP more than 120 % of baseline value. If a patient presents hypertension for two consecutive measurements, the case will be considered a drop out.An adequate response will be defined as the absence of hypotension or nausea/vomiting during the period from induction of spinal anesthesia to uterine incision prior to fetal delivery.

The results of this study will define the minimum effective dose of phenylephrine to prevent post-spinal hypotension and nausea/vomiting secondary to hypotension in Cesarean section, thus optimizing the safety profile with respect to maternal and fetal side effects of this vasopressor.

Study Design

Study Type:

Interventional

Allocation:

Randomized

Intervention Model:

Single Group Assignment

Masking:

Double

Primary Purpose:

Prevention

Official Title:

Phenylephrine Dose-Finding Study to Minimize Hypotension Due to Spinal Anesthesia for Cesarean Section

Study Start Date :

Aug 1, 2006

Actual Study Completion Date :

Dec 1, 2006

Outcome Measures

Primary Outcome Measures

The primary outcome will be the minimum dose of phenylephrine which effectively prevents both hypotension and nausea/vomiting between intrathecal injection of the local anesthetic and delivery of the fetus. []