Transverse Abdominal Plane Anesthesia for Abdominal Wall Reconstruction

Abdominal Wall Reconstruction: Postoperative Outcomes Using Transverse Abdominal Plane Anesthesia

The aim of this study is to evaluate the short-term postoperative outcomes in the abdominal wall reconstruction population using an intraoperative local anesthetic infusion. A prospective randomized double blind study of patients undergoing component separation will be performed in order to assess the following outcomes:

1. Length of Stay (LOS)
2. Return of bowel function
3. Narcotic pain medication requirements
4. Nausea and emesis
5. Pain scores

One group will be the control group (group A) and the other will be the study group (group B). Neither patient nor physician will know which group they have been assigned. Informed consent will be obtained during pre-operative evaluation in the clinic prior to the day of surgery as stated above. Relevant medical history will be entered into a secure database. Information collected will include patient demographics, medical co-morbidities, history of prior procedures, preoperative pain scores, postoperative nausea, emesis, pain scores, dermatomal anesthesia, adjuvant narcotic usage, return of bowel function and length of stay (LOS).

Patients will be randomly separated into 2 groups at the time of surgery through the randomization log of the investigational drug service (IDS) pharmacy. At the request of the attending surgeon a solution will be prepared and delivered to the operating room in a blinded fashion concealed within a shielded vial.

During the abdominal component separation, dissection of the tissue planes housing the sensory fibers will be exposed to allow insertion of a large spinal needle under direct visualization on each side of the abdominal wall. Depending on the study group, the attending surgeon will inject an unknown solution (solution A or B) of either 30ml of Exparel ((bupivacaine liposome injectable suspension) 1.3% ( 13.3mg/ml)). The final test solution will be prepared in the IDS pharmacy by adding a 20 mL Exparel vial and 40cc of normal saline for a total of 60cc with a bupivacaine concentration of 0.44%. This will then be split into two 30cc solutions to be injected into each side of the transverse abdominal plane. A patient in the placebo group will be injected with 30cc of Normal Saline into the TAP region on each side of the abdomen.

All patients, independent of their study group will be provided with Patient Controlled Analgesics (PCA) using Hydromorphone or orally dosed narcotic/acetaminophen combo analgesics to ensure adequate post-operative pain control. The pain scores, dermatomal level of anesthesia, nausea, emesis, return of bowel function and length of stay will be logged into the electronic medical record. Once data collection is complete the groups will be revealed and all of the data will undergo statistical analysis.

Inclusion Criteria:

• Subjects to be included are all competent patients, 18 years of age or older, who undergo abdominal component separation for a hernia.

Exclusion Criteria:

• Patients who are not having abdominal component separation or are receiving another form of regional anesthesia will be excluded.
• Patients younger than 18 years of age will be excluded.
• Amide-type local anesthetics, such as bupivacaine, are metabolized by the liver.
• Patients' with hepatic disease, because of their inability to metabolize local anesthetics normally, are at a greater risk of developing toxic plasma concentrations and will therefore be excluded from the study.