Up-Down Determination of the ED90 of Phenylephrine for Hypotension Prophylaxis in Cesarean Delivery
Status:
Terminated
Trial end date:
2009-07-01
Target enrollment:
Participant gender:
Summary
This study is designed to determine the ED90 for an infusion of phenylephrine to prevent
spinal induced low blood pressure in parturients presenting for an elective cesarean
delivery. The up-down methodology (UDM) is commonly used study method to determine the dose
of a drug that causes the desired effect in over 90% of the subjects to whom it given. For
example: the investigators want to know what is the best dose of phenylephrine (from a range
of commonly used doses) to prevent a drop in blood pressure during cesarean delivery ninety
times out of one hundred when it is given at that dose. The ED90 is the effective dose at
which 90% of subjects will have a "positive" response to a phenylephrine infusion, i.e. no
drop in blood pressure. The investigators hypothesize that the ED90 will be between 40 - 60
mcg/min.
The primary outcome measure is the ED90 for phenylephrine infusions that prevents a drop in
blood pressure in women undergoing cesarean delivery.