Transverse Abdominis Plane (TAP) Block After Cesarean Delivery
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT01170702 |
Recruitment Status :
Completed
First Posted : July 27, 2010
Last Update Posted : January 19, 2017
|
- Study Details
- Tabular View
- Results Submitted
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Postoperative Pain Pregnancy Obesity | Drug: 0.9% Normal Saline Drug: 0.2% Ropivacaine Drug: 0.5% Ropivacaine Drug: 0.75% Ropivacaine | Phase 4 |
Cesarean delivery is the most commonly performed surgical procedure in the United States today, with over 1.2 million cases performed in 2005. One of the most important aspects of cesarean delivery is the provision of safe, effective postoperative analgesia for the mother, while simultaneously ensuring minimal side effects for both the mother and neonate. Studies have suggested that a multimodal approach to post-cesarean pain utilizing both intravenous, oral, and neuraxial opioids and non-steroidal anti-inflammatory drugs is highly effective in providing effective analgesia.
A significant component of post-cesarean pain is incisional pain from the Pfannenstiel incision on the anterior abdominal wall. The sensory supply to the skin, muscles, and parietal peritoneum of the anterior abdominal wall is derived from the anterior rami of T7-L1. After exiting the spinal column, these nerves proceed through the lateral abdominal wall within the transversus abdominal fascial plane, terminating in the anterior abdominal wall.
Recent studies have suggested that blocking these afferent sensory nerves with local anesthetics, as part of a multimodal postoperative pain regimen, provides superior pain relief in terms of decreased pain scores and morphine consumption for up to 48 hours postoperatively. The technique utilized for these studies employed a surface anatomical approach to the transversus abdominal fascial plane via the lumbar triangle of Petit, a technique validated in both cadaveric and radiologic studies. However, as ultrasonography has emerged as the "gold standard" for initiating many nerve blocks, reports have described the successful use of ultrasound imaging for initiation of transversus abdominis plane (TAP) blocks for both abdominal surgeries and cesarean deliveries.
In the published studies investigating the use of the TAP block for post-operative analgesia, either ropivacaine or bupivacaine was utilized in concentrations of 0.75% and 0.375%, respectively. Studies comparing ropivacaine with bupivacaine for use in interscalene, femoral, or sciatic nerve blocks have found no difference in terms of potency, time to onset or duration of postoperative analgesia between the two local anesthetics. Although no similar studies have been done with TAP blocks, one can assume that utilization of ropivacaine for this nerve block would yield similar results in terms postoperative analgesia. Moreover, the cardiotoxicity of ropivacaine has been shown to be significantly less than bupivacaine, making it a safer alternative for use in nerve blocks when used in high doses.
Risk factors for respiratory depression after the administration of neuraxial opioids in the non-obstetric population include morbid obesity and obstructive sleep apnea. For the obstetric population, a study of 856 patients revealed that all 8 patients who experienced respiratory depression after intrathecal morphine for cesarean delivery were markedly obese. Furthermore, the onset of respiratory depression after intrathecal morphine can occur up to 12 hours after administration, a time period when the patient is not being as closely monitored as she is during the 1:1 nursing care in the recovery room. Therefore, it is the investigators policy on the Labor and Delivery unit to not administer intrathecal morphine to any parturient with a history of obstructive sleep apnea or a BMI > 40 kg/m2. These patients often require intravenous opioid patient-controlled analgesia postoperatively, which has been shown to provide inferior pain relief and greater opioid consumption than neuraxial opioids. The current clinical standard is to administer the TAP block to those patients who have not received morphine in their neuraxial anesthetic. The TAP block offers a novel addition to the management of post-cesarean pain for this patient population.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 120 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | The Postoperative Analgesic Efficacy of Varied Concentrations of Ropivacaine Used for the Transverse Abdominis Plane (TAP) Block After Cesarean Delivery |
Study Start Date : | January 2010 |
Actual Primary Completion Date : | January 2017 |
Actual Study Completion Date : | January 2017 |

Arm | Intervention/treatment |
---|---|
Placebo Comparator: Group 1
TAP Block utilizing 15mL of 0.9% normal saline per side
|
Drug: 0.9% Normal Saline
The abdominal muscle layers will be located by placing the ultrasound transducer perpendicular to the coronal anatomic plane at the T-10 dermatome level in the patient's midaxillary line. Under ultrasound guidance, a 70mm or 90mm, 21 gauge blunted Stimuplex needle will be advanced from the skin until the tip reaches the fascial layer between the internal oblique and transversus abdominis. 15ml of the study drug will be injected incrementally. The needle will then be removed and the process repeated in the same manner on the patient's opposite side. |
Experimental: Group 2
TAP Block utilizing 15ml of 0.2% ropivacaine per side
|
Drug: 0.2% Ropivacaine
The abdominal muscle layers will be located by placing the ultrasound transducer perpendicular to the coronal anatomic plane at the T-10 dermatome level in the patient's midaxillary line. Under ultrasound guidance, a 70mm or 90mm, 21 gauge blunted Stimuplex needle will be advanced from the skin until the tip reaches the fascial layer between the internal oblique and transversus abdominis. 15ml of the study drug will be injected incrementally. The needle will then be removed and the process repeated in the same manner on the patient's opposite side. |
Experimental: Group 3
TAP Block utilizing 15ml of 0.5% ropivacaine per side
|
Drug: 0.5% Ropivacaine
The abdominal muscle layers will be located by placing the ultrasound transducer perpendicular to the coronal anatomic plane at the T-10 dermatome level in the patient's midaxillary line. Under ultrasound guidance, a 70mm or 90mm, 21 gauge blunted Stimuplex needle will be advanced from the skin until the tip reaches the fascial layer between the internal oblique and transversus abdominis. 15ml of the study drug will be injected incrementally. The needle will then be removed and the process repeated in the same manner on the patient's opposite side. |
Experimental: Group 4
TAP Block utilizing 15ml of 0.75% ropivacaine per side
|
Drug: 0.75% Ropivacaine
The abdominal muscle layers will be located by placing the ultrasound transducer perpendicular to the coronal anatomic plane at the T-10 dermatome level in the patient's midaxillary line. Under ultrasound guidance, a 70mm or 90mm, 21 gauge blunted Stimuplex needle will be advanced from the skin until the tip reaches the fascial layer between the internal oblique and transversus abdominis. 15ml of the study drug will be injected incrementally. The needle will then be removed and the process repeated in the same manner on the patient's opposite side. |
- hydromorphone consumption [ Time Frame: 24 hours ]
- opioid consumption (morphine equivalents) [ Time Frame: 48 hours ]
- opioid consumption (morphine equivalents) [ Time Frame: 72 hours ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- ASA II-III patient
- > 18 years of age who is pregnant
- presenting for a cesarean delivery via Pfannenstiel incision who is eligible to receive a spinal anesthetic with 0.75% bupivacaine and fentanyl and whose is not eligible to receive intrathecal morphine due to a BMI >40 kg/m2.
Exclusion Criteria:
- < 18 years of age
- contraindication to placement of a spinal anesthetic
- contraindication to use of non-steroidal anti-inflammatory drugs (NSAIDs)
- patients receiving medical therapies considered to result in tolerance to opioids
- patients with a history of established chronic pain, (e.g. chronic low back pain, fibromyalgia or headaches), defined as requiring regular medical follow-up with pain specialists, as well as recent use (within the year preceding pregnancy) of opioid analgesics as an outpatient
- patients with a history of diabetes mellitus
- patients undergoing a vertical midline skin incision
- patients who are undergoing a cesarean delivery after a failed vaginal trial of labor
- patients who had a prior epidural placed for labor analgesia during the same hospital encounter.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01170702
United States, Illinois | |
Northwestern University | |
Chicago, Illinois, United States, 60611 |
Principal Investigator: | Edward Yaghmour, M.D. | Northwestern University |
Responsible Party: | Edward (Ted) Yaghmour, Assistant Professor, Northwestern University |
ClinicalTrials.gov Identifier: | NCT01170702 |
Other Study ID Numbers: |
STU00008429 |
First Posted: | July 27, 2010 Key Record Dates |
Last Update Posted: | January 19, 2017 |
Last Verified: | January 2017 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Cesarean Delivery Ropivicaine TAP block |
Pain, Postoperative Postoperative Complications Pathologic Processes Pain Neurologic Manifestations Ropivacaine |
Anesthetics, Local Anesthetics Central Nervous System Depressants Physiological Effects of Drugs Sensory System Agents Peripheral Nervous System Agents |