Spinal Anesthesia for Cesarean Delivery: Bupivacaine With or Without Fentanyl

Condition(s) targeted: Pain

Intervention: Bupivacaine (Drug); Bupivacaine, fentanyl (Drug)

Phase: N/A

Status: Completed

Sponsored by: Samuel Lunenfeld Research Institute, Mount Sinai Hospital

Official(s) and/or principal investigator(s):
Alison J Macarthur, MD, Principal Investigator, Affiliation: Mount Sinai Hospital, New York

The safest form of anesthesia for Cesarean section is a spinal anesthetic. All spinal anesthetics contain a local anesthetic and/or a narcotic. A drug named bupivacaine is the most commonly used local anesthetic in spinal anesthetics for Cesarean deliveries in North America. Another drug named fentanyl is the most commonly used narcotic. This study will look at whether a spinal anesthetic with 15mg of bupivacaine alone will be the same as a spinal anesthetic with 12mg of bupivacaine and 15ug of fentanyl.

Official title: Spinal Anesthesia for Cesarean Delivery: Bupivacaine With or Without Fentanyl

Study design: Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Primary outcome: The primary outcome is the maximal degree of abdominal sensation felt by the patient during surgery.

Secondary outcome:

Speed of onset of block to T4 dermatome (minutes), as well as highest level of block (dermatomal level) and degree of motor block (Bromage scale)

The degree of patient discomfort will be evaluated using a 10 cm linear visual analog scale (VAS).

The amount of additional IV analgesia administered during the intraoperative period.

Time to regression of block (minutes)

Duration of analgesia (hours)

Incidence of side effects: Intraoperative pruritus, nausea and vomiting in the absence of hypotension, somnolence, shivering, euphoria or dysphoria and respiratory depression will be evaluated.

Dose of vasopressor(s) given during surgery

Lowest Mean Arterial Pressure during surgery (=2/3 diastolic pressure + 1/3 systolic pressure).

Patient satisfaction. A number of questions answered on a Likert Scale will be asked post-Cesarean section.

Neonatal arterial blood gas results (pH) and 1 and 5-minute APGAR scores (1 - 10) will be recorded

Detailed description: There have been many studies looking at different doses and combinations of bupivacaine and fentanyl but there is no agreement among anesthesiologists as to the best combination of drugs. The main problem with bupivacaine is that it causes hypotension (low blood pressure). When fentanyl is added to bupivacaine, a lower dose of bupivacaine can be used so that there is less of a fall in blood pressure. The main problem with fentanyl is itchiness and sleepiness. In the case of an emergency Cesarean section, the extra time needed to draw-up and administer a second medication may make a difference to the health of the baby. Our goal is to determine whether high dose bupivacaine (15mg) alone will produce spinal anaesthesia for cesarean delivery equivalent to 12mg of intrathecal hyperbaric bupivacaine in combination with 15ug of intrathecal fentanyl.

Minimum age: 16 Years. Maximum age: 50 Years. Gender(s): Female.

Criteria:

Inclusion Criteria:

- healthy patients (ASA 1 or 2)

- BMI < 40

- height between 5 & 6 feet

Exclusion Criteria:

- parturients with pregnancy induced hypertension or preeclampsia

- parturients with significant cardiac, renal or other organ-system disease which

preclude choice of spinal anesthesia

- emergency delivery

- triplet or greater multiple gestation

Mount Sinai Hospital, Toronto, Ontario M5G1X5, Canada

Starting date: January 2009
Last updated: November 19, 2009