Effect of the Superficial Cervical Plexus Block in the Hypotensive Anesthesia of Ear Surgery.

Patients meeting the inclusion criteria were randomly assigned into two groups, the control group and the study group, by a computer-generated randomization program. All patients in both group will be informed by the study methods,aim, side effect in clear language, written consent will be taken in clear spoken and written language, All patients of both groups ,once arrived to the OR, monitor will be attached, baseline SBP, DBP,MAP,SPO2,PULSE will be recorded, General anaesthesia (GA) will be induced with intravenous inj. of propofol 2-2.5 mg/kg, , fentanyl 1 microgram/kilogram (μg/kg). and atracuruim 0.5 mg/kg was given for muscle relaxation .

In study Group patients, superficial CPB will be administered in a supine position with the head turned opposite to the side of the block using ultrasound guidance .

Local anaesthetic will be injected alongside the posterior border of the muscle 2-3 cm in cranial and caudal directions. Using a 'fan' technique, the local anaesthetic will be administered subcutaneously and behind the sternocleidomastoid muscle. Ten millilitres of 0.25% bupivacaine were injected for each side of the block using a 1.5-inch 24-gauge needle. [2].

General anaesthesia will maintained with O2 + air (50:50), 3-litre flow, sevoflurane 2% to 2.5% and an intravenous inj. of atracuiruim 0.01 mg/kg every 20 min. An intraoperative rise in heart rate (>100/min) and systolic blood pressure (≥ 20% from pre-induction value) will be recorded and managed by giving intravenous inj. of fentanyl 0.5 microgram/kg in incremental doses (dose of fentanyl did not exceed 3 μg/kg for less than three hours of surgery). At the end of the surgery, the reversal of residual neuromuscular block will be done and the patient will be extubated. The patient will be then transferred to the recovery room and the severity of pain will be assessed by a VAS scale ( visual analog score scale ), which is a straight line denoting one end with no pain and the other end with the worst pain. VAS score was calculated as follows: 0, no pain; 1-3, mild pain; 4-6, moderate pain; 7-9, severe pain; 10, worst pain. The VAS score will be assessed when the patient could follow verbal commands.

Evaluation of block for adequate analgesia intraoperatively will be done in terms of the total requirement of intravenous analgesics through the observation of heart rate and blood pressure and postoperatively, it will be done by observing VAS score, time of first demand for a bolus of rescue analgesic (intravenous paracetamol) and total requirement of rescue analgesic in 24 hours.. Pulse, mean blood pressure (BP), oxygen saturation (SpO2) and any side effects were also noted.