Transversus Abdominis Plane Block With Liposomal Bupivacaine for Pain After Cesarean Delivery in a Multicenter, Randomized, Double-Blind, Controlled Trial.

BACKGROUND: In women undergoing cesarean delivery under spinal anesthesia with intrathecal morphine, transversus abdominis plane (TAP) block with bupivacaine hydrochloride (HCl) may not improve postsurgical analgesia. This lack of benefit could be related to the short duration of action of bupivacaine HCl. A retrospective study reported that TAP block with long-acting liposomal bupivacaine (LB) reduced opioid consumption and improved analgesia following cesarean delivery. Therefore, we performed a prospective multicenter, randomized, double-blind trial examining efficacy and safety of TAP block with LB plus bupivacaine HCl versus bupivacaine HCl alone. METHODS: Women (n = 186) with term pregnancies undergoing elective cesarean delivery under spinal anesthesia were randomized (1:1) to TAP block with LB 266 mg plus bupivacaine HCl 50 mg or bupivacaine HCl 50 mg alone. Efficacy was evaluated in a protocol-compliant analysis (PCA) set that was defined a priori. The primary end point was total postsurgical opioid consumption (oral morphine equivalent dosing [MED]) through 72 hours. Pain intensity was measured using a visual analog scale. Adverse events (AEs) after treatment were recorded through day 14. RESULTS: Total opioid consumption through 72 hours was reduced with LB plus bupivacaine HCl versus bupivacaine HCl alone (least squares mean [LSM] [standard error (SE)] MED, 15.5 mg [6.67 mg] vs 32.0 mg [6.25 mg]). This corresponded to an LSM treatment difference of -16.5 mg (95% confidence interval [CI], -30.8 to -2.2 mg; P = .012). The area under the curve of imputed pain intensity scores through 72 hours supported noninferiority of LB plus bupivacaine HCl versus bupivacaine HCl alone (LSM [SE], 147.9 [21.13] vs 178.5 [19.78]; LSM treatment difference, -30.6; 95% CI, -75.9 to 14.7), with a prespecified noninferiority margin of 36 (P = .002). In an analysis of all treated patients, including those not meeting criteria for inclusion in the PCA, there was no difference in postsurgical opioid consumption between groups. In the LB plus bupivacaine HCl group, 63.6% of patients experienced an AE after treatment versus 56.2% in the bupivacaine HCl-alone group. Serious AEs after treatment were rare (≈3% in both groups). CONCLUSIONS: TAP block using LB plus bupivacaine HCl as part of a multimodal analgesia protocol incorporating intrathecal morphine resulted in reduced opioid consumption after cesarean delivery in the PCA set. Results suggest that with correct TAP block placement and adherence to a multimodal postsurgical analgesic regimen, there is an opioid-reducing benefit of adding LB to bupivacaine TAP blocks after cesarean delivery (ClinicalTrials.gov identifier: NCT03176459).

Randomized trial of transversus abdominis plane block with liposomal bupivacaine after cesarean delivery with or without intrathecal morphine.

STUDY OBJECTIVE: To investigate efficacy and safety of liposomal bupivacaine (LB) transversus abdominis plane (TAP) block with or without intrathecal morphine (ITM) compared with ITM alone for postsurgical analgesia after cesarean delivery (CD). DESIGN: Multicenter, open-label, randomized trial (NCT03853694). SETTING: Operating room. PATIENTS: Women with term pregnancy of 37 to 42 weeks scheduled for elective CD under spinal anesthesia. INTERVENTION: Patients were randomized 1:1:1 to LB 266 mg TAP block alone (LB group), ITM 50 µg followed by LB 266 mg TAP block (LB + ITM group), or ITM 150 µg alone (ITM group). All groups received the same postsurgical multimodal analgesic regimen. MEASUREMENTS: The LB and LB + ITM groups were compared with the ITM group for all efficacy outcomes. Postsurgical opioid consumption in morphine milligram equivalents (MMEs) through 72 h was compared by assessing noninferiority before testing superiority. Postsurgical pruritus severity was assessed on an 11-point numerical rating scale. MAIN RESULTS: Between March 4, 2019, and January 10, 2020, 153 patients (LB, n = 52; LB + ITM, n = 48; ITM, n = 53) were enrolled. Baseline characteristics were comparable across groups. The LB group had statistically noninferior postsurgical opioid consumption through 72 h compared with the ITM group (least squares mean [LSM], 19.2 vs 16.4 MMEs; LSM treatment ratio, 1.17 [95% confidence interval (CI), 0.74-1.86]; noninferiority P < 0.0034) as did the LB + ITM group (LSM, 14.6 vs 16.4 MMEs; LSM treatment ratio, 0.89 [95% CI, 0.55-1.44]; noninferiority P < 0.0001). The LB and LB + ITM groups had significantly reduced pruritus severity scores through 12, 24, 48, and 72 h compared with the ITM group (P ≤ 0.0121). Adverse events occurred in 58%, 85%, and 81% of the LB, LB + ITM, and ITM groups, respectively. CONCLUSIONS: LB TAP block with or without ITM resulted in statistically noninferior postsurgical opioid consumption through 72 h, reduced pruritus, and favorable safety compared with ITM in women undergoing CD.

Casopitant and ondansetron for postoperative nausea and vomiting prevention in women at high risk for emesis: a phase 3 study.

HYPOTHESIS: Postoperative nausea and vomiting (PONV) are associated with a variety of complications. Neurokinin subtype 1 receptor antagonists have antiemetic activity in the postoperative setting, and the neurokinin subtype 1 receptor antagonist casopitant mesylate (GW679769) was well tolerated and effective at reducing the incidence of PONV in phase 1 and phase 2 trials. DESIGN: A multicenter, randomized, double-blind, parallel-group, phase 3 analysis was designed to evaluate the safety and efficacy of casopitant in combination with a single intravenous dose of the serotonin subtype 3 receptor antagonist ondansetron hydrochloride for the prevention of PONV in the perioperative setting. SETTING: Forty-three centers in 11 countries. PATIENTS: We studied 484 women at high risk for developing PONV scheduled to undergo operations associated with high emetogenic risk. INTERVENTIONS: The women were randomized to receive a single dose of intravenous ondansetron, 4 mg, or oral casopitant, 50 mg, in combination with intravenous ondansetron, 4 mg. MAIN OUTCOME MEASURES: The primary end point was the proportion of patients who achieved a complete response, defined as no vomiting, retching, or rescue therapy. Patients received a balanced anesthetic regimen. RESULTS: Between March 20 and August 31, 2006, 484 patients were enrolled in the study. Patients in the casopitant plus ondansetron group had a 68.7% rate of complete response during the first 24 hours after surgery compared with 58.7% in the ondansetron-only group (P = .03). The difference between groups in complete response from 24 to 48 hours (63.4% with ondansetron only vs 70.0% with ondansetron plus casopitant) was not significant. No vomiting for 0 to 24 hours was observed in 89.7% of the casopitant plus ondansetron group compared with 74.9% of the ondansetron-only group (P < .001). Oral casopitant administered in combination with ondansetron was well tolerated. CONCLUSIONS: The results of this pivotal phase 3 study demonstrate that the combination of casopitant and ondansetron was superior to ondansetron only in patients at high risk for PONV. Trial Registration clinicaltrials.gov Identifier: NCT00326248.