Comparison of Ultrasound-Guided Quadratus Lumborum Plane Block and External Oblique Intercostal Plane Block for Postoperative Analgesia After Laparoscopic Cholecystectomy: A Two-Center Randomized Controlled Trial

<i>Background and Objectives</i>: Although various regional anesthesia techniques are commonly used for laparoscopic cholecystectomy (LC), to date, no randomized controlled trial has compared the effectiveness of Quadratus Lumborum Plane Block (QLB) and External Oblique Intercostal Plane Block (EOIPB) in LC. Our aim was to compare the effectiveness of ultrasound-guided QLB and EOIPB in providing postoperative analgesia after LC. <i>Materials and Methods</i>: In this two-center, randomized controlled trial, patients undergoing LC were divided into QLB and EOIPB groups. Our primary outcome was the postoperative pain scores measured using the Numerical Rating Scale (NRS) at predetermined intervals. Secondary outcomes included opioid consumption, Riker Sedation-Agitation Scale (RSAS) score, and patient satisfaction. <i>Results</i>: The NRS pain scores at postoperative 30th minute, 4th, 12th, and 24th hours were significantly lower in the QLB group (<i>p</i> < 0.05). Patients in the QLB group required significantly less tramadol compared to the EOIPB group (<i>p</i> < 0.000). The QLB group also demonstrated lower RSAS scores (<i>p</i> = 0.005), indicating a smoother recovery process. Patient satisfaction scores were markedly higher in the QLB group (<i>p</i> < 0.000). Although both blocks were well-tolerated with no differences in side effects, EOIPB was associated with higher opioid consumption, indicating its relatively limited effectiveness. <i>Conclusions</i>: To conclude, this study highlights that QLB is a more effective option for postoperative analgesia and improves patient satisfaction after LC. EOIPB may serve as a viable alternative for some patients; however, given the advantages of QLB in pain control and recovery, it stands out as a more preferable method.