Anesthesia, Obstetric, Cesarean Section
Conditions
Keywords
Spinal anesthesia, bupivacaine, Sensory dermatomal level
Brief summary
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.
Detailed 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.
Interventions
DRUGIntrathecal 1.6 ml 0.75% bupivacaine in 8.25% dextrose combined with 15 mcg fentanyl and 150 mcg preservative-free morphine
Patients will receive standard intrathecal medications for urgent and scheduled cesarean delivery at the study site. All study subjects will receive bupivacaine, fentanyl, and morphine.
Sponsors
Oregon Health and Science University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
FEMALE
Age
15 Years to 55 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of participants with spinal failure | 90 minutes | A composite outcome that will be categorized as yes if there is either preoperative or intraoperative spinal failure. Preoperative failure will be defined as failure to achieve a T4 level to pinprick by the 15-minute timepoint. Intraoperative failure will be defined as pain (VAS \> 0) that requires anesthesia provider medication administration. Pain will be queried at time of skin incision, fetal delivery, uterine exteriorization, uterine interiorization or end of uterine closure, and end of skin closure. If VAS \> 0, the anesthesia provider will ask the patient if they would like analgesic medication. Discomfort at any other time during the cesarean delivery that is treated with neuraxial or intravenous analgesia will also count. Pain will be rated according to the scale: 0 = no pain, 10 = worst pain imaginable |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of participants with conversion to another anesthetic technique | 90 minutes | Conversion to general anesthesia or activation of the epidural catheter for intraoperative pain |
| Number of participants with inadequate anesthesia | 90 minutes | Analgesic supplementation with ketamine, \> 20 mg propofol, \> 2 mg midazolam, \> 10 mg parental morphine equivalents, or intraperitoneal chloroprocaine |
| Patient satisfaction assessed by 5-point Likert scale, minimum value=1, maximum value=5, with higher values representing better patient satisfaction | 2 Hours | Patient satisfaction upon arrival to the post-anesthesia care unit, rated on a 1-5 Likert scale with higher values representing better patient satisfaction |
Countries
United States
Outcome results
None listed