Transversus abdominis plane block with liposomal bupivacaine and its effect on opiate use after weight loss surgery: a randomized controlled trial.

BACKGROUND: Liposomal bupivacaine (LB), as an extended-release local anesthetic, may provide lasting pain control and therefore decrease the need for narcotics in the immediate postoperative period. OBJECTIVES: The aim of this study was to evaluate whether transversus abdominis plane (TAP) block with LB decreased the use of postoperative narcotics compared with regular bupivacaine (RB) and no TAP block in patients undergoing weight loss procedures. SETTING: A large, metropolitan, university-affiliated, tertiary hospital. METHODS: Patients undergoing laparoscopic Roux-en-Y gastric bypass, sleeve gastrectomy, or sleeve-to-bypass conversion over 1 year were randomized to receive TAP block using LB, TAP block with RB, or no block in a double-blind, randomized controlled trial. The outcomes measured were postoperative use of opiates, pain score, length of stay, time to ambulation, and nausea. Data were analyzed using χ2 test and analysis of variance F test. RESULTS: Two hundred nineteen patients were included in the study. Fentanyl patient-controlled analgesia usage was not significantly different between the groups (LB 351.4 versus RB 360.7 versus no TAP block 353.9, P = .97) at 48 hours post operation. The pain scores (scale 1-10) were similar among the groups with the mean for the LB group at 4.3, and RB and no TAP block groups both at 4.7 (P = .35). The type of block or lack of block did not significantly impact the length of stay, time to ambulation, or presence of nausea. CONCLUSION: The LB TAP block did not significantly reduce the total opiate pain medication consumption nor did it reduce pain scores among bariatric surgery patients.

Site localization and characterization of pain during radiofrequency ablation of the pulmonary veins.

BACKGROUND: Characteristics of radiofrequency (RF) lesions producing pain with an 8-mm catheter during pulmonary vein (PV) ablation have not been prospectively studied. METHODS: We studied 46 (30 men, age 56 +/- 10 years) patients with AF who underwent RF ablation of PVs. PV isolation was achieved by using an 8F, 8-mm Biosense ablation catheter (Biosense Webster, Diamond Bar, CA, USA) guided by intracardiac echocardiography (ICE). An electroanatomic map was used to document the location of all RF lesions and the time; PV location and maximum temperature of every lesion were recorded. Location of the esophagus was determined by magnetic resonance imaging prior to the procedure and by both ICE and barium swallows during procedure. RESULT: A total of 1,448 (33 +/- 12) RF lesions were delivered to 180 veins. Thirty-nine patients (85%) had at least one lesion associated with pain (mean: 8 +/- 5 lesions) during ablation. The RF generator setting during lesions resulting in pain sensation was 48.6 +/- 7.0 Watts and 51.5 +/- 2.9 degrees C. Maximum temperature attained at the time of pain sensation was 45.7 +/- 4.2 degrees C. By logistic regression analysis the left superior PV (OR 1.54, CI 1.06-2.24, LS vs RI, P < 0.05) and left inferior PV (OR 2.74, CI 1.79-4.19, LI vs RI, P < 0.001) location were both positively correlated with the production of pain. The location of lesions associated with pain was not near the esophagus during any of the pain-producing lesions. CONCLUSION: Pain sensation is relatively common during RF ablation of PVs. There was no correlation between pain and the location of esophagus. Pain was more common during RF ablation of left inferior and left superior PVs.