Epidural analgesia is considered the standard of care but cannot be provided to all patients Liposomal bupivacaine has been approved for field blocks such as transversus abdominis plane (TAP) blocks but has not been clinically compared against other modalities. In this retrospective propensity matched cohort study we thus tested the primary hypothesis that TAP infiltration are noninferior (not worse) to continuous epidural analgesia and superior (better) to intravenous opioid analgesia in patients recovering from major lower abdominal surgery. 318 patients were propensity matched on 18 potential factors among three groups (106 per group): 1) TAP infiltration with bupivacaine liposome; 2) continuous Epidural analgesia with plain bupivacaine; and; 3) intravenous patient-controlled analgesia (IV PCA). We claimed TAP noninferior (not worse) over Epidural if TAP was noninferior (not worse) on total morphine-equivalent opioid and time-weighted average pain score (10-point scale) within first 72 hours after surgery with noninferiority deltas of 1 (10-point scale) for pain and an increase less of 20% in the mean morphine equivalent opioid consumption. We claimed TAP or Epidural groups superior (better) over IV PCA if TAP or Epidural was superior on opioid consumption and at least noninferior on pain outcome. Multivariable linear regressions within the propensity-matched cohorts were used to model total morphine-equivalent opioid dose and time-weighted average pain score within first 72 hours after surgery; joint hypothesis framework was used for formal testing. TAP infiltration were noninferior to Epidural on both primary outcomes (p<0.001). TAP infiltration were noninferior to IV PCA on pain scores (p = 0.001) but we did not find superiority on opioid consumption (p = 0.37). We did not find noninferiority of Epidural over IV PCA on pain scores (P = 0.13) and nor did we find superiority on opioid consumption (P = 0.98). TAP infiltration with liposomal bupivacaine and continuous epidural analgesia were similar in terms of pain and opioid consumption, and not worse in pain compared with IV PCA. TAP infiltrations might be a reasonable alternative to epidural analgesia in abdominal surgical patients. A large randomized trial comparing these techniques is justified.
Infiltración con bupivacaína liposomal en el plano transverso del abdomen para la analgesia post quirúrgica en la reparación de la hernia umbilical abdominal abierta: resultados de una cohorte de 13 pacientes.
Liposomal bupivacaine infiltration into the transversus abdominis plane for postsurgical analgesia in open abdominal umbilical hernia repair: results from a cohort of 13 patients.
J Pain Res. 2014 Aug 16;7:477-82. doi: 10.2147/JPR.S65151. eCollection 2014.
BACKGROUND: Achieving adequate control of postsurgical pain remains a challenge in patients undergoing abdominal surgery. Transversusabdominis plane (TAP) infiltration has been shown to provide postsurgical analgesia following lower abdominal surgery. We assessed the safety and efficacy of a prolonged-release liposomal formulation of the local anesthetic bupivacaine administered via infiltration into the TAP in a cohort of patients undergoing open abdominal umbilical hernia repair. METHODS: Patients included in the study were 18-75 years of age, had American Society of Anesthesiologists physical classification status 1-3, and underwent open abdominal umbilical hernia repair with ultrasound-guided TAP infiltration immediately after surgery using an equal-volume bilateral infusion of liposomal bupivacaine 266 mg (diluted to 30 mL in normal saline). Outcome measures included patient-reported pain intensity (11-point numeric rating scale), satisfaction with postsurgical analgesia (5-point Likert scale), incidence of opioid-related adverse events, and time to first use of supplemental rescue analgesia. RESULTS: Thirteen patients underwent surgery and received bilateral TAP infiltration with liposomal bupivacaine; TAP infiltration failed in the first patient. Mean numeric rating scale pain scores were 0.6 immediately before TAP infiltration and remained ≤2.3 through 120 hours after infiltration; mean scores at 120 hours and 10 days were 0.9 and 0.4, respectively. Ten patients (77%) required supplemental analgesia; median time to first use was 11 hours. At discharge and day 10, 54% and 62% of patients, respectively, were "extremely satisfied" with postsurgical analgesia (Likert score 5). There were no opioid-related or other adverse events. CONCLUSION: Although the current study was limited by both its lack of a control group and its small size, to our knowledge, it is the first published report on use of liposomal bupivacaine for TAP infiltration. In this cohort, liposomal bupivacaine was observed to be well tolerated with encouraging analgesic efficacy.