Conditions: Spinal Induced Hypotension in Cesarean Delivery
Allocation: NA | Intervention model: SINGLE_GROUP
Enrollment: 45
Healthy volunteers: yes

Brief 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.

Detailed description:

Arms:
arm 1: None

Interventions: intervention 1: Phenylephrine infusion
Intervention descriptions: intervention 1: Up-down, biased coin design

Protocol document: