Posterior quadratus lumborum block (QLB2): 0.2ml/kg vs 0.4ml/kg of 0.25% levobupivacaine in pediatric laparoscopic abdominal surgery. A comparative study

Abstract

Introduction The Quadratus Lumborum Block (QLB) which is a trun- cal plane block, is increasing in favor as part of multimodal analgesia for abdominal surgeries due to its analgesic effect which gives a good coverage for visceral pain as compared to oral and intravenous analgesics. The QLB being a plane block, depends on volume of local anes- thetic (LA) for its efficacy. However, to date there are no consensus for the lowest effective volume of LA for the QLB in both adult and pediatric groups. The pediatric age group particularly are sensitive to small changes in drug doses, which is more important to ascertain the lowest ef- fective volume. Hence, we conducted a prospective, ran- domized, double blinded study to compare the effects of two volumes of LA in the QLB in pediatric patients un- dergoing laparoscopic abdominal surgeries. Material and Methods A total of 52 American Society of Anesthesiologist phys- ical status I or II patients, aged 1-12 years old were re- cruited and randomized into two groups, A & B. A stand- ard general anesthesia protocol was conducted. Group A patients received 0.2 ml/kg of levobupivacaine 0.25% and Group B patients received 0.4 ml/kg of levobupiva- caine 0.25% for the QLB2 that was done. Postoperatively patients were reviewed for FLACC and VAS pain scores and side effects up to 24 hours. Results The result showed that Group A was non-inferior com- pared to Group B in mean difference of pain scores, pain score severity (p value of 1.000), mean pain scores across 24-hour time line, requirement of rescue analgesia (p value of 0.569) and patients’ parents’ satisfaction scores (p value of 0.664). Discussion and Conclusion In conclusion, a volume of 0.2 ml/kg which is further away from the LA toxic dose, was proven to be non-inferior to 0.4 ml/kg of levobupivacaine for QLB2 done in pediatric laparoscopic abdominal surgeries. However larger and multi-centered studies, employing different types of surgeries and possibly lower volumes of LA need to be done to further ascertain the lowest effective volume for the QLB in pediatric surgery.

Keywords

• pediatrics
• anaesthetics
• local anesthetics
• levobupiva- caine
• laparoscopy