The block has been shown to be the result of abdominal analgesia as a result of application between the quadratus lumborum (QL) muscle and the leaves in the thoracolumbar fascia.

In this block, local anesthetic drugs are administered between the quadratus lumborum (QL) muscle and the anterior leaf in the thoracolumbar fascia.

In this way, it has been reported that it provides a good analgesia as it relieves somatic pain better in upper and lower abdominal surgeries.

The mechanism of QLB analgesic contains many theories. This study includes the research relationship between the effect of fascial pressure and the success of the association block. We will use the ultrasound guided anterior Quadratus Lumborum Block. A peripheral nerve block catheter will be placed between the quadratus lumborum muscle and the psoas muscle with ultrasound.The pressure between the fascia and the pressure line added to the catheter tip will be measured.A peripheral nerve block catheter will be placed between the quadratus lumborum muscle and the psoas muscle with ultrasound. The pressure between the fascia and the pressure line added to the catheter tip will be measured.

Inclusion Criteria:

Patients who were in the American Society of Anesthesiologists (ASA) I-III class

• Underwent laparoscopic cholecystectomy

Exclusion Criteria:

• Previous history of preoperative opioid use,
• Allergy to local anesthetics,
• The presence of any systemic infection,
• Uncontrolled arterial hypertension,
• Uncontrolled diabetes mellitus
• Presence of infection in the block area,