Evaluation of the Typical Spinal Block During Cesarean Delivery

Oregon Health & Science University (OHSU)

Status: Invitation-only

Conditions: Cesarean Section; Anesthesia, Obstetric

Treatments: Drug: Intrathecal 1.6 ml 0.75% bupivacaine in 8.25% dextrose combined with 15 mcg fentanyl and 150 mcg preservative-free morphine

Study type: Observational

Funder types: Other

Identifiers

NCT06206044

25364

Details and patient eligibility

About

This will be a prospective, observational, single-center study to evaluate the accuracy of sensory testing by blunt 16-gauge plastic cannula during the 15 minutes after spinal injection for predicting spinal failure. While previous studies assessed the minimal sensory level required for painless cesarean delivery at skin incision or delivery, no studies have assessed the accuracy of sensory testing at an earlier time point.

Full description

Primary Objective:

1. Evaluate the accuracy of sensory testing with blunt plastic 16-gauge cannula during the 15 minutes after spinal injection for predicting spinal failure. Cephalad sensory dermatomal levels will be assessed at 1 (t1), 3 (t3), 5 (t5), 7 (t7), 9 (t9), 11 (t11), 13 (t13), and 15 (t15) minutes after intrathecal 1.6 ml 0.75% bupivacaine in 8.25% dextrose combined with 15 mcg fentanyl and 150 mcg morphine (study solution). Spinal failure, which is defined as inability to achieve a T4 level to pinprick by the 15-minute timepoint or intraoperative pain (VAS > 0) requiring treatment

Secondary Objectives:

1. Conversion to another anesthetic technique (general anesthesia or activation of the epidural catheter)
2. Inadequate anesthesia (analgesic supplementation with ketamine, > 20 mg propofol, > 2 mg midazolam, > 10 mg parental morphine equivalents, or intraperitoneal chloroprocaine).
3. Patient satisfaction upon arrival to the postanesthesia care unit, rated on a 1-5 Likert scale

A sample size calculation

Population: 250 pregnant females undergoing non-emergency cesarean section delivery in the Labor & Delivery Operating Rooms at Oregon Health & Science University.

Number of Sites: Single center trial

Study Duration: Institutional Review Board approval has been obtained. Study initiation, enrollment, and data collection is expected to take 24 months. Data analysis, manuscript writing, editing, submission and revision to a peer-reviewed journal is expected to take an additional 6 months.

In summary, the study should be completed in under 3 years.

Subject Participation Duration: Total time of subject participation including time for recruitment, enrollment, data collection during the preanesthesia consult, and post-consult data collection will be less than 3 hours.

Estimated Time to Complete Enrollment: Estimated time from enrollment into study of the first subject to enrollment into study of the last subject is 24 months.

Enrollment: 250 estimated patients

Sex: Female

Ages: 15 to 55 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients undergoing cesarean delivery under spinal or combined spinal epidural anesthesia
• BMI between 20 and 40 kg/m2
• Height between 5 feet 2 inches and 5 feet 10 inches.
• English and non-English speaking patients, if interpretive services are available

Exclusion criteria

• Patient refusal
• Contraindications to neuraxial anesthesia (coagulopathy, CNS pathology, infection at site of needle puncture)
• Allergy to any study medications
• Use of epidural anesthesia
• Emergency (red) cesarean delivery
• Conditions that impact dermatomal sensory testing including spinal cord injury with sensory deficits and abdominoplasty
• Prison inmates
• Decisionally impaired individuals
• Pregnancies involving multiple fetuses

Trial design

250 participants in 1 patient group

Study Cohort

Description:

Healthy pregnant women of BMI between 20 and 40 kg/m2, height between 5 feet 2 inches and 5 feet 10 inches, who are having cesarean delivery under spinal or combined spinal epidural anesthesia.

Treatment:

Drug: Intrathecal 1.6 ml 0.75% bupivacaine in 8.25% dextrose combined with 15 mcg fentanyl and 150 mcg preservative-free morphine