A Randomized Clinical Trial to Compare the Addition of Epinephrine (no Epinephrine, 100mcg, and 200mcg) to the Standard Dose of Hyperbaric Bupivacaine 12mg, Fentanyl 20mcg and Morphine 150mcg in Scheduled C-sections.
Description:
Spinal anesthesia is the most common type of anesthetic for C-section, but its major
limitation is that the duration of the anesthesia may be less than the operative time. Repeat
C-section is particularly associated with increased operative time and is often performed
under a continuous spinal-epidural (CSE) technique. The epidural component is, however,
untested and may not provide adequate anesthesia, thus necessitating the risk general
anesthesia. Epinephrine may be used to prolong spinal anesthesia. This study will evaluate
the optimal dose of epinephrine as an adjunct to usual spinal doses of 1.6 mL hyperbaric
bupivacaine + 20 mcg preservative free fentanyl + 150 mcg preservative free morphine.
Adding epinephrine to hyperbaric bupivacaine helps in prolonging the duration of anesthesia
and the quality of analgesia. However, the time to regression of the block effective for
surgical anesthesia is not known for a C-section. Better quantification of this factor would
help in choosing a spinal technique over a CSE in obstetric patients. This study seeks to
quantify the duration of effective spinal anesthesia with the addition of either 100 or 200
mcg of epinephrine to an intrathecal mixture of hyperbaric bupivacaine and narcotics.
With early local anesthetics such as metycaine, nupercaine, or tetracaine, epinephrine was
shown to intensify and prolonged their effects. Subsequent studies suggest that subarachnoid
anesthesia with a combination of hyperbaric bupivacaine combined with an opioid and an
adrenergic drug may be superior to techniques relying solely on local anesthetic drug.
However, most of the studies were conducted in an orthopedic population for ambulatory and
total joint arthroplasty for elderly patients.
Currently, it is well accepted that the addition of intrathecal narcotics will enhance the
quality and duration of a spinal block.
Two investigations sought to determine the ED 95 dose of hyperbaric bupivacaine in
combination with fentanyl and morphine to provide surgical anesthesia for operative success
for cesarean delivery. Despite differences in spinal technique (sitting vs. lateral) the ED95
dose was 11.2 and 12 respectively. However, the mean duration of surgeries in those studies
were significantly less (41 ± 15 and 64 ± 16 min respectively) than the mean duration of an
elective C-section in our institution (90 ± 27 min with a 95th percentile of 135 min).
Since 12mg hyperbaric bupivacaine is the upper limit of acceptable doses for an elective
C-section this study will evaluate the efficacy of epinephrine to extend the duration of
effective surgical anesthesia.
Condition:
Pregnancy
Treatment:
100 mcg Epinephrine
Start Date:
October 2019
Sponsor:
University of Florida
For More Information:
https://clinicaltrials.gov/show/NCT03335293