ABSTRACT
BACKGROUND: Pain management for bilateral total knee arthroplasty (BTKA) often combines adductor canal block (ACB) with periarticular infiltration (PAI). However, concerns arise regarding local anesthetic toxicity. This study evaluated the efficacy and safety of different bupivacaine concentrations in simultaneous BTKA. METHODS: Patients undergoing simultaneous BTKA under spinal anesthesia were included in the study. They received ACB with 50 mg bupivacaine for each thigh. The patients were then randomized into two groups. Group A was administered a PAI of 100 mg bupivacaine per knee (totaling 300 mg bupivacaine for ACB and PAI). Group B received a PAI with 50 mg bupivacaine per knee (totaling 200 mg bupivacaine for ACB and PAI). Postoperative pain was assessed using a visual analog scale at 4-h intervals for 48 h after surgery. Plasma bupivacaine concentrations were measured at eight specified times. Postsurgery walking ability was also evaluated. RESULTS: Among the 57 participants analyzed, visual analog scale pain scores revealed no significant differences between the two groups. An interim analysis of plasma bupivacaine concentrations in both groups indicated no significant disparities. In group B, 93.1% managed to walk with assistance within 48 h, as opposed to group A's 71.4% (P = 0.041). CONCLUSIONS: Combining ACB with 100 mg bupivacaine and PAI with another 100 mg bupivacaine provided effective pain relief. This combination also had a better safety profile and led to more patients walking postsurgery than when combining ACB with 100 mg bupivacaine and PAI with 200 mg bupivacaine. Thus, ACB combined with PAI with a total dose of 200 mg bupivacaine appears suitable for simultaneous BTKA. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03249662).
ABSTRACT
BACKGROUND: Achieving optimal analgesia with few side effects is the goal of pain management after cesarean delivery. Intrathecal (IT) morphine is the current standard but ultrasound-guided quadratus lumborum block (QLB) may offer superior pain control with fewer side effects. This study compared the pain-free period after cesarean delivery among parturients who received spinal block with IT morphine, with IT morphine and bilateral QLB, or only bilateral QLB. METHODS: Parturients having elective cesarean delivery under spinal block were randomized and allocated into IT morphine 0.2 mg with sham QLB (Group IT), IT morphine 0.2 mg and bilateral QLB with 0.25% bupivacaine 25 ml in each side (Group IT+QLB), or bilateral QLB with 0.25% bupivacaine 25 ml in each side (Group QLB). A PCA pump was connected after completion of the QLB or sham block. The first time to PCA morphine requirement was recorded and compared. RESULTS: Eighty parturients were included. Analysis of Group QLB was terminated early because at the second interim analysis, median pain-free period was significantly shorter in Group QLB [hours (95%CI): 2.50 (1.04-3.96) in Group IT vs. 7.75 (5.67-9.83) in IT+QLB vs. 1.75 (0.75-2.75) in QLB (p < 0.001)]. The median (min, max) amount of morphine required during 24 h was 5.5 (0-25) in Group IT vs. 5.0 (0-36) in IT+QLB vs. 17.5 (1-40) mg in Group QLB (p < 0.001). In the final analysis the median pain-free period was 2.50 (1.23-3.77) hours (95%CI) in Group IT (n = 27) vs. 8.02 (5.96-10.07) in IT+QLB (n = 28). (p = 0.027). CONCLUSION: US-QLB used in conjunction with IT morphine yielded a statistically significant longer median pain-free period compared with standard IT morphine alone. However, QLB alone provided inferior pain control compared with standard IT morphine. When combined with IT morphine, QLB could provide additional analgesic benefit as a part of multimodal analgesic regimen, especially during the early postoperative period. TRIAL REGISTRATION: ClinicalTrials.gov no. NCT03199170 Date registered on June 22, 2017. Prospectively registered.
