Comparison of types 2 and 3 quadratus lumborum muscle blocks : Open inguinal hernia surgery in patients with spinal anesthesia.

OBJECTIVE: The efficacy of quadratus lumborum muscle block (QLB) in abdominal surgery is known; however, the efficacy of different QLB types is unclear. The objective of this study was to investigate the effects of ultrasound-guided QLB type 2 and type 3 on postoperative opioid consumption and pain scores in patients undergoing inguinal hernia surgery. MATERIAL AND METHODS: In this study 60 patients undergoing open inguinal hernia surgery were randomly assigned to 3 groups. Group QLB2 received ultrasound-guided QLB type 2 and group QLB3 received ultrasound-guided QLB type 3 with 0.25% 20 mL bupivacaine. In the control group (group C) no intervention was performed. Postoperative analgesia was performed intravenously with 1000 mg paracetamol every 6 h and patient-controlled analgesia with fentanyl. Postoperative visual analog scale scores (VAS), opioid consumption, and first analgesic requirement time were evaluated. RESULTS: Fentanyl consumption was significantly higher in group C compared to the other groups at all time intervals (p < 0.05). Fentanyl consumption was significantly higher in group QLB2 compared to QLB3 at the 4-8 h, 8-24 h, and total 24 h. Passive VAS 4h and 8 h, active VAS 4h, 8h, and 12 h were significantly lower in group QLB3 compared to QLB2 (p < 0.05). The first analgesic time was significantly later in group QLB2 compared to group C (280.52 ± 89.20 min and 183.75 ± 42.79 min, respectively) and even later in group QLB3 compared to the other two groups (463.42 ± 142.43 min, p < 0.05). CONCLUSION: The use of QLB2 and QLB3 decreased postoperative opioid consumption and pain scores in patients undergoing inguinal hernia surgery. Furthermore, QLB3 provided more effective and longer lasting postoperative analgesia and lower opioid consumption compared to QLB2.