Complex cesarean delivery with an intraoperative transversus abdominis plane (TAP) block

COMFORT Trial: Complex Obstetric Management With Focused Regional Transversus Abdominis Plane Block

Phase 4 Interventional University of Tennessee · NCT06925152

This study tests whether giving a TAP nerve block with bupivacaine during complex cesarean deliveries lowers the amount of opioid pain medicine patients need after surgery.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment120 (estimated)
Ages18 Years to 50 Years
SexFemale
SponsorUniversity of Tennessee Academic / other
Locations1 site (Memphis, Tennessee)
Trial IDNCT06925152 on ClinicalTrials.gov

What this trial studies

This interventional Phase 4 study enrolls patients undergoing cesarean delivery in the setting of complex obstetric surgery and compares an intraoperative TAP block with bupivacaine versus a placebo TAP block. Participants receive the assigned TAP intervention during their cesarean and postoperative opioid use is tracked and converted to morphine milliequivalents (MME) to measure opioid consumption. The trial focuses on patients with prior abdominal surgeries, adhesions, multiple prior cesareans, or other factors that increase surgical complexity. The primary outcome is postoperative opioid use, with secondary interest in pain control and recovery measures at the single study site.

Who should consider this trial

Good fit: Ideal candidates are patients having a cesarean delivery with features of complex obstetric surgery (for example prior laparotomy, adhesions, or three or more prior cesareans) who are not chronic opioid users and are receiving neuraxial rather than general anesthesia.

Not a fit: Patients who have chronic opioid use or substance abuse, chronic kidney disease, allergies to bupivacaine or oral analgesics, those undergoing cesarean hysterectomy, or those who receive general anesthesia are unlikely to benefit or are excluded from participation.

Why it matters

Potential benefit: If successful, this approach could reduce postoperative opioid requirements and improve pain control and recovery after complex cesarean deliveries.

How similar studies have performed: Previous randomized and observational studies in lower abdominal and cesarean surgery have shown intraoperative TAP blocks can reduce opioid consumption and improve pain scores, supporting the rationale for this trial.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion criteria:

Patient has a history of a least one of the following:

* Prior exploratory laparotomy
* History of non-obstetric open intra-abdominal surgery
* History of three or more prior cesarean deliveries
* History of intra-abdominal or pelvic adhesive disease
* History of abdominoplasty
* History of abdominal re-exploration surgery

Exclusion Criteria:

* Received general anesthesia
* History of less than 3 cesarean deliveries if do not meet other inclusion criteria
* History of chronic opioid use
* History of substance abuse (i.e. alcohol, methamphetamine/amphetamine, abuse of prescription opioid medication, or heroin use)
* History of chronic kidney disease
* Allergies to bupivacaine or oral analgesics
* Patient preference
* Cesarean hysterectomy
* Administration of ≥4mg morphine to epidural
* Loss to follow-up

Where this trial is running

Memphis, Tennessee

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Complex Obstetric SurgeryPerioperative Pain ManagementCesarean DeliveryPostoperative Pain ControlComplex obstetric surgeryPerioperative pain managementcesarean deliverypostoperative pain control
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.