Lumbar Plexus Block vs Fascia Iliaca Block After Hip Arthroscopy: A Non-inferiority Study

If the patient is willing to participate and signs the consent, he/she will be randomized to one of the two treatment groups:

1. Lumbar Plexus Block
2. Fascia Iliaca Block

The patient will undergo general anesthesia as by the attending anesthesiologist assigned to the case. No intraoperative restrictions will be required for this study. Once in the PACU, the patient will be assessed and if their pain score is ≥ 4 on the NRS, the patient will be randomized to a lumbar plexus block or fascia iliaca block.

Patients will be monitored during block performance with standard ASA monitors. All patients will receive 2 L of oxygen via a nasal cannula. Sedatives will be titrated to effect. Midazolam 1-2 mg, and fentanyl 50-100 mcg will be used for sedation.

The fascia iliaca block will be performed in a standard fashion as described2. The patient will be placed in a supine position. The ipsilateral groin will be prepped and cleaned with chlorhexidine. An ultrasound machine with a linear transducer covered with a sterile tegaderm will be utilized. The transducer is placed inferior to the inguinal ligament until the femoral artery is located. The probe is then moved laterally until the Sartorius muscle is seen. A skin wheal with 3ml of 1% lidocaine is made and a 2-inch blunt tip needle is inserted in plane. The needle is seen to pierce the fascia iliaca and 1-2 ml of 0.25% Preservative Free bupivacaine with 1:200,000 epinephrine is injected to confirm correct needle placement between the fascia iliaca and iliopsoas muscle. An injection will be deemed adequate if local anesthetic is seen to separate these two layers in a medial to lateral direction. A total of 30ml of the above solution will be injected.