Please select the eligibility criteria that correspond to the clinical trial below.
Title: Prophylactic Ephedrine to Reduce Fetal Bradycardia After Combined Spinal Epidural Labor Analgesia: a Randomized Double Blind Placebo-controlled Study
Brief Summary: The combined spinal epidural (CSE) technique has become increasingly popular for labor pain because of its rapid onset and superior first stage analgesia. However, increased risk for early profound fetal bradycardia (EPFB) following CSE continues to be a concern. Various factors are implicated in the etiology of EPFB but the cause is unknown. Ephedrine administration prior to CSE analgesia may help reduce the risk of EPFB, but to date, nobody has studied the impact of a single dose of intravenous (IV) ephedrine given at the time of CSE administration during labor. The purpose of this study is to measure the incidence of EPFB after combined spinal epidural analgesia using standard definitions. The incidence of EPFB will be compared between patients who receive prophylactic ephedrine or placebo at the time of CSE placement.


Options:
A: Inclusion criteria:

* Ability to speak and understand English
* Term (37-42 weeks' gestation)
* Cephalic presentation
* Singleton pregnancy
* ASA 3 or less
* No pregnancy-induced hypertension
* No chronic hypertension
* BMI \<40
* No evidence of pre-epidural fetal heart rate abnormality
* No IUGR or low AFI. ASA 1-3 women who request epidural analgesia Informed consent signed upon admission to L\&D

Exclusion Criteria:

* ASA 4 women, BMI \> 39
* Contraindication to epidural analgesia
* Twin pregnancy
* Preterm labor
* Severe preeclampsia
* Decision to perform CS prior to epidural insertion
* Unable to read or speak English
* Unable or unwilling to sign the IFC
B: Inclusion Criteria:

* elective cesarean section applying spinal anesthesia
* ≥ week 37 of gestation
* Singleton pregnancy

Exclusion Criteria:

* Suspicion of any hypertensive disease
* Parturient in labor
C: Inclusion Criteria:

* Healthy pregnant women
* Over 18 years old
* ASA 1-2
* Undergoing elective caesarean section
* Height over 160 cm or under 180 cm

Exclusion Criteria:

* Allergic reactions to ephedrine or phenylephrine
* High blood levels of bilirubin
* HELPP syndrome
* Preeclampsia (pregnancy-induced hypertension)
* Non singleton pregnancies
D: Inclusion Criteria:

* Elective Caesarean section
* Consent to be in the study
* Age 18-45
* ASA 1 or 2

Exclusion Criteria:

* Patient refusal
* Patients with known allergy to ondansetron will be excluded
* Contraindications to spinal anesthetic

  * Known Coagulopathy (acquired e.g. anticoagulation or existing such as liver disease; using patient history, physical examination to determine bleeding risks, a platelet count under 100 or a PT INR over 1.4)
  * Severely altered anatomy (e.g. post surgical changes)
  * Existing neurological deficits (Women with a history of migraine or tension headache will be allowed to enroll. More severe conditions with daily life limiting symptoms will be excluded. Examples include epilepsy, pseudotumor cerebri, prior stroke with persistent neurologic deficits, or any motor or sensory neuropathy with existing deficits)
  * Skin infection overlying site

Answer: A