Study: NCT03328481

Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: Loss-of-resistance Quadratus lumborum block
Description: ِA blunted 22-G, 11 mm, short-bevel facet needle will be introduced in the paravertebral line at the level of L3 or L4, in 30-45 degree to the skin directing it laterally. Once the skin barrier is breached, the needle will be withdrawn back so that the tip lies just under the skin. The needle will be advanced through the posterior thoracolumbar fascia and a first fast pop sensation will be felt when the needle pierced it. With further advancement of the needle, a second deep pop will be felt after it pierces the middle thoracolumbar fascia. At this point, the needle will be in the plane of the quadratus lumborum block type II. After careful aspiration, the 30 mLs of local anaesthetic will be injected. The needle will be visualized by the ultrasound by another physician to ensure safety.

Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: Ultrasound-guided Quadratus lumborum block
Description: A broadband (5-8 MHz) convex transducer will be placed transversely in the abdominal flank above the iliac crest to identify the external oblique, internal oblique, transversus abdominis muscles and aponeurosis. Then the external oblique muscle will be followed posteriorly until its posterior border is visualized (hook sign), and the posterior aspect of the Quadratus lumborum muscle is confirmed. A 22-G, 11-mm, short-bevel facet needle will be advanced under direct ultrasound visualization in-plane from anterolateral to postero-medial. Then the 30 ml of local anesthetic (bupivacaine 0.25 %) will be injected into the lumbar inter-facial triangle (LIFT) behind the quadratus lumborum muscle using hydro-dissection.

Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: General anesthesia
Description: Patients will receive 2 mg of midazolam and 8 mg of dexamethasone IV; then, they will be transferred to the operating room to receive a standard general anesthetic. Perioperative monitoring will include ECG, non-invasive arterial blood pressure, and pulse oximetry (SpO2) and end-tidal carbon dioxide. Anesthesia will be induced by propofol 1.5-2.5 mg/kg, atracurium 0.5 mg/kg, and fentanyl 2 mcg/kg to facilitate the insertion of an endotracheal tube. Anesthesia will be maintained by isoflurane 1-2% end-tidal concentration to maintain systolic arterial blood pressure and heart rate within + 20% of the baseline values. Ventilation will be adjusted to maintain normocapnia.

Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: General anesthesia
Description: Patients will receive 2 mg of midazolam and 8 mg of dexamethasone IV; then, they will be transferred to the operating room to receive a standard general anesthetic. Perioperative monitoring will include ECG, non-invasive arterial blood pressure, and pulse oximetry (SpO2) and end-tidal carbon dioxide. Anesthesia will be induced by propofol 1.5-2.5 mg/kg, atracurium 0.5 mg/kg, and fentanyl 2 mcg/kg to facilitate the insertion of an endotracheal tube. Anesthesia will be maintained by isoflurane 1-2% end-tidal concentration to maintain systolic arterial blood pressure and heart rate within + 20% of the baseline values. Ventilation will be adjusted to maintain normocapnia.