Study of the Effect of Intramuscular Ephedrine on the Incidence of Nausea and Vomiting During Elective Cesarean Section

Phase 2

Completed

Brief Summary: The purpose of this research study is to investigate if the incidence of nausea and vomiting that subjects experience during and after a Cesarean section can be reduced by giving a shot of the drug ephedrine into the thigh muscle at the time of spinal anesthesia administration.

Detailed Description: This research project is designed to study the medication ephedrine, when it is given as a routine part of the anesthesia for elective Cesarean section. Ephedrine is a medication that is widely used in labor and in vaginal and operative (Cesarean section) deliveries to help maintain a woman's blood pressure within its normal range, especially after spinal and epidural anesthesia has been administered. The purpose of this study is to determine if ephedrine, when given intramuscularly (\<IM\> as a shot in the muscle), at the time of spinal anesthesia administration, can help to decrease the incidence of nausea and vomiting subjects experience during and after a Cesarean section. This study will compare women who receive ephedrine to a similar group of women who receive a normal saline placebo. In addition to looking at the difference in the incidence of nausea and vomiting perioperatively, this study will also evaluate if the administration of IM ephedrine helps the baby to receive more blood from the placenta after anesthesia has been administered to the mother. This will be evaluated by performing a simple blood test, drawn from the umbilical cord, after the baby is born.

Recruitment & Eligibility

Inclusion Criteria

Must be pregnant with a single baby
Must be at term in their pregnancy (estimated gestational age of at least 38 weeks)
Must be scheduled for an elective Cesarean section
Must be between 60-70" tall
Must be free of severe systemic disease (ASA class I or II)

Exclusion Criteria

Contraindication to spinal anesthesia
Any allergy to any of the medications included in the study
History of pregnancy-induced hypertension or preeclampsia
History of preexisting hypertension
Diabetes mellitus
Hyperemesis gravidum
Previous perioperative nausea and vomiting
History of motion sickness
Women carrying a fetus with a known abnormality will also be excluded from the study

Arm && Interventions

Group	Intervention	Description
Saline Placebo	Saline Placebo	Drug: Saline Placebo 0.5 mL, IM (in the muscle), one time

Primary Outcome Measures

Name	Time	Method
Pre-Induction Nausea Score	immediately pre-induction	Subject's self-rated nausea level on a scale of 0-3 immediately prior to induction of spinal anesthesia, where 0=no nausea, 1=mild nausea, 2=moderate nausea, and 3=severe nausea
Subject's Self-rated Intra-operative Nausea Level on a Scale of 0-3, Where 0=no Nausea, 1=Mild Nausea, 2=Moderate Nausea, and 3=Severe Nausea.	intra-operation	Subjects were asked to rate their nausea level on a scale of 0-3, where 0=no nausea, 1=mild nausea, 2=moderate nausea, and 3=severe nausea, five times during their procedure: 1) Immediately prior to skin incision, 2) immediately following delivery of the baby, 3) following reinternalization of the uterus, 4) following closure of the fascia, 5) following closure of the skin. The numbers given by the subject were then averaged to determine the average level of nausea intra-operatively for each subject.
Post-Operation Nausea Score	post-operation	Subjects were asked to rate their nausea level on a scale of 0-3, where 0=no nausea, 1=mild nausea, 2=moderate nausea, and 3=severe nausea two times after the conclusion of their surgery: 1) upon arrival in the PACU, and 2) immediately prior to discharge from the PACU. The numbers given by the subject were then averaged to determine the average level of nausea post-operative for each subject.