The study will be conducted only after approval from the institutional ethics committee and will be registered with the clinical trials registry India (CTRI). A detailed pre-anaesthetic check-up and investigations will be done for all patients. Informed consent will be taken from parents/assent from the child (wherever applicable) before the participation in the study. An anaesthesiologist with an experience of at least 25 successful supra-inguinal FICB in children will carry out the procedure. Observation and data collection will be done by an independent observer, who will be blinded to the drugs given.
Patients will be kept nil per oral (NPO) for at least 6 hours prior to surgery as per standard guidelines. Perioperative anaesthetic management will be standardized. The children will be premedicated with oral midazolam (0.5 mg/Kg) 30 min before the surgical procedure. After arrival in the operating room, a 22/24 Gauge (G) peripheral intravenous catheter will be inserted. Standard monitoring will be applied, including non-invasive blood pressure (NIBP), electrocardiograph (ECG) with heart rate (HR) and pulse oximetry (SpO₂).
 Intravenous (IV) Fentanyl 1 mcg/Kg will be administered and IV propofol 2-3 mg/Kg will be used for induction. Airway will be secured by an appropriately sized proseal laryngeal mask airway (PLMA). The maintenance will be provided by sevoflurane 2 to 2.5% in an equal mix of oxygen and air.
The patient will be administered USG guided supra-inguinal FICB under all aseptic precautions. The USG probe (M-turbo broadband linear array, 6-13 MHz paediatric probe Sonosite^®, Bothell, Washington, USA) will be sheathed. With the patient in supine position, the probe will be placed just medial to the anterior superior iliac spine (ASIS) in the sagittal plane. The superior edge of the transducer will be rotated 30 degrees medially towards the umbilicus to approximate a parallel course with the ilium curve and then tilted/toggled laterally to identify internal oblique muscle, transversus abdominis muscle, fascia iliaca (FI), iliacus muscle and ilium bone. Bow tie sign formed by the muscle fascia of the sartorius muscle and abdominal muscles will be identified. Using an in-plane approach, a 22 G, 80-mm Pajunk^® needle will be introduced at the caudal edge of the transducer and advanced in a cephalad direction under visualization until the tip lies below the FI but above the iliacus muscle. Using hydro-dissection, the fascia iliaca will be separated from the iliacus muscle to create a space. After negative aspiration, confirmation of correct needle tip location will be obtained by hydro-dissection of the plane with normal saline followed by injection of drug in small increments with gentle intermittent aspiration. An injection will be considered successful if spread of LA is observed cranial to the point where the iliacus muscle dives under the abdominal muscles. Patients in Group A will receive 0.75mL/Kg of 0.25% bupivacaine mixed with 2mL normal saline containing 0.5 mcg/Kg dexmedetomidine and group B will receive 0.75mL/Kg of 0.25% bupivacaine mixed with 2mL normal saline containing 0.1 mg/Kg dexamethasone. During the injection, the distribution of local anaesthetic (LA) solution will be observed as a hypo echoic enlargement on USG. The patient would then be handed over for surgery. If there will be a change of more than 20% in arterial blood pressure or heart rate during surgery then IV fentanyl 1mcg/Kg will be given to the patient. At the end of the surgery, anaesthesia will be terminated and the PLMA will be removed. Thereafter the patient will be shifted to the post anaesthesia care unit (PACU).
All patients will be administered IV paracetamol 15 mg/Kg 8 hourly in the postoperative period. The duration of postoperative analgesia, defined as time (in minutes) from giving of the FICB to the time to the first analgesic request in the postoperative period will be recorded. Pain will be assessed by an independent anaesthesiologist using Modified Objective Pain Scale (MOPS) postoperatively at 1 hour, 3 hours, 6 hours and 24 hours. If the pain score is more than or equal to 4, IV fentanyl will be given as the rescue analgesic at a dose of 1mcg/Kg and noted. IV Fentanyl at a dose of 1 mcg/Kg will be repeated if there is no reduction in pain score after 30 minutes. Total amount of fentanyl (mcg/kg) administered in 24 hours will be recorded. Any drug side effects (hypotension, sedation and bradycardia) will also be recorded and appropriately managed. Patients will also be monitored for local anaesthetic systemic toxicity (LAST) and any such event will be managed as per American Society of Regional Anesthesia (ASRA) checklist. Sedation will be assessed as per University of Michigan Sedation Scale (UMSS) at 1 hour, 3 hours, 6 hours and 24 hours postoperatively. Parent satisfaction will be assessed using a five-point satisfaction scale 24 hours postoperatively.