EFFICACY OF TRANSVERSE ABDOMINIS PLANE BLOCK WITH LIPOSOMAL BUPIVACAINE FOR POST C-SECTION ANALGESIA
Abstract Number: T-27
Abstract Type: Original Research
The purpose of our study was to show the benefit of extended pain relief with liposomal bupivacaine with TAP block in patients with neuraxial anesthesia that receive intrathecal morphine. Liposomal Bupivacaine suspension is currently indicated for single-dose infiltration into the surgical site for postsurgical analgesia. This formulation combines bupivacaine with DepoFoam®, a proven product delivery technology that delivers medication over a extended time period. A single dose of Liposomal Bupivacaine is shown to provide significant reductions in cumulative pain scores with a decrease in opioid consumption.
Twelve patients were selected who were scheduled for elective C-Section under spinal anesthesia. Intrathecal preservative free morphine for postoperative analgesia. Bilateral TAP Blocks were performed,at the end of the surgery, under ultrasound guidance. 20ml of liposomal bupivacaine mixture(liposomal bupivacaine mixed with 0.25% bupivacaine)was injected on each side. A standard order for intravenous acetaminophen and ketorolac was placed for breakthrough pain. Patients were evaluated at 6, 12, 24, 48, and 72 hours. Data was collected regarding pain relief using VAS score, and amount of opioids consumed. We performed a chart review on 20 patients who did not receive TAP block but received intrathecal morphine and data was collected on pain scores and amount of opioid consumption.
Results: Patients who received bilateral TAP blocks with liposomal bupivacaine had pains scores (mean±SD) of 1.0±1.4, 1.4±2.1, 1.7±1.9, 1.9±3.3 and 1.9±2.3 at 6, 12, 24, 48 and 72 hours respectively. Only 3 out of 12 patients used oxycodone with the mean total dose of 18±10 mg of Oxycodone. One of the 3 patients only requested pain medication on postoperative day 3 and received 5 mg of oxycodone 3 times that day. The mean pain score at the first request for pain medication was 1.3±2.3 on a scale of 0-10. The mean pain score recorded at all request for pain medication was 0.8±1.8. 12 out of 20 patients without TAP block used 24±17 mg of oxycodone. Pain scores were recorded only at the time when the patient was requesting pain medication and only 11 out of 12 patients had recorded pain scores. The mean pain score at the first request for pain medication was 6±2.3. The mean pain score recorded at all request for pain medication was 5.6±1.9.
TAP Blocks have been extensively used in the obstetrics, have been show to reduce analgesic requirements and pain scores after C-Section and can be used as an effective adjuvant for breakthrough pain. Previous studies reported rest pain to be reduced at 6, 12, 24 but not 48 hours and dynamic pain was reduced at 6 and 12 but not 24 hours. Although there is a large difference in both pain scores and opioid use between the two groups in our study, we need to review another 40 charts of patients who received intrathecal morphine without a TAP block to properly power the study.