Percutaneous nephrolithotomy (PNL) is frequently used today for renal stones. percutaneous nephrolithotomy (PNL) procedure has become the treatment of choice for many patients with symptomatic renal stones . Patients undergoing PNL suffer from acute postoperative pain, despite a multimodal analgesic regime.

This is a randomised controlled trial efficacy of the anterior Quadratus Lumborum Block (QLB) in terms of analgesic efficacy in patients who undergo percutaneous nephrolithotomy.

Many analgesic procedures such as NSAID, opioid and regional anesthesia procedures are used as a part of multimodal analgesia for postoperative Percutaneous nephrolithotomy pain.

In this study we will use the ultrasound -guided anterior Quadratus Lumborum Block . Local anesthesic will be injected between quadratus lumborum muscle and psoas muscle with ultrasound.Analgesic effect of this block will be detected by using morphine consumption and visual analogue scale .

Inclusion Criteria:

• Patients who were in the American Society of Anesthesiologists (ASA) I-III class and underwent elective Percutaneous nephrolithotomy

Exclusion Criteria:

• Previous history of opioid use preoperatively,

  • Allergy to local anesthetics,
  • The presence of any systemic infection,