Hip Arthroscopy; Femoral Nerve Block or Fascia Iliaca Block: A Randomized Control Trial

Patients undergoing hip arthaoscope will be conducted to operating room, where standard intraoperative monitoring will be applied, pulse oximetry, 5 lead ECG then peripheral cannulation. Anesthesia will be induced with fentanyl 1.5μg/kg, midazolam 0.1-0.5 mg/kg, cis-atracurium 0.15 mg/kg followed by intubation. Then anesthesia will be maintained with isoflurane1-1.5% Patients will be divided into two groups according to the randomization envelopes:

Group (A) :( 15 patients) the fascia iliaca block: Patient in the supine position, skin will be disinfected and linear transducer (8-12 MHZ) will be positioned to identify the femoral artery and the iliopsoas muscle and fascia iliaca. The transducer will be moved laterally until the sartorius muscle is identified. Echogenic needle (Bajunk, 80 m.m length) will be inserted in-plane, as it will pass through fascia iliaca, the fascia will be first seen indented by the needle. While piercing the fascia, a "pop" may be felt, and the fascia may be seen to "snap" back on the US image (SONOSITE). After negative aspiration, 1-2 mL of local anesthetic is injected to confirm the proper injection plane between the fascia and the iliopsoas muscle. A proper injection will result in the separation of the fascia iliaca by the local anesthetic in the medial-lateral direction from the point of injection as described. Releasing the pressure of the transducer may reduce the resistance to injection and improve the distribution of local anesthetic. If the spread is deemed inadequate, additional injections laterally or medially to the original needle insertion or injection can be made to facilitate the medial-lateral spread (the injection is stopped and the needle repositioned before continuing. Additional injections may be made to ensure adequate spread) (Yun MJ, et al., 2009). 40 mL of 0.25% levobupivacaine will be given. The success of the nerve block is best predicted by documenting the spread of local anesthetic toward the femoral nerve medially and underneath the sartorius muscle laterally (L. Hanna, et al., 2014).

Group (B): Control group, (15 patients) femoral nerve block: With the patient in the supine position, the skin over the femoral crease will be disinfected and the transducer will be positioned to identify the femoral artery and nerve. If the nerve is not immediately apparent lateral to the artery, tilting the transducer proximally or distally often helps to image and highlight the nerve from the iliacus muscle and the more superficial adipose tissue. Once the femoral nerve is identified, the needle will be inserted in-plane in a lateral to medial orientation and advanced toward the femoral nerve (Mariano E.R ,et al., 2013). Once the needle tip is adjacent (either above, below, or lateral) to the nerve, and after careful aspiration, 1-2 mL of local anesthetic will be injected to confirm proper needle placement that will push the femoral nerve away from the injection followed by total volume of 20 ml 0.25% levobupivacaine (Lamaroon A. et al., 2014) The blocks will be performed by the expert anesthesia staff, and then positioning of patients will be done for the hip arthroscopy. Another blinded doctor to the type of block received will attend the surgery and manage and record any additional intraoperative analgesic requirements.

Postoperatively, timing for the first rescue analgesia will be recorded, if VAS is more than 5, 25 mg pethidine will be given. If no improvement second rescue analgesia in form 5 mg morphine will be given .Also total narcotics demand will be recorded with measurement of (VAS) hourly in the first 4 hours postoperatively then every 4 hours for 8 hours .Early ambulation will be assessed and recorded together with assessing the weakness of quadriceps femoris.