Ketamine or Neostigmine for Serratus Anterior Plane Block in Modified Radical Mastectomy

The patient will be placed in Lateral Decubitus with a surgical side upwards with arm abduction. A linear ultrasound transducer (6-13 MHz) will be placed on the patient's midaxillary line in the transverse plane, at the level of the fifth rib, with the indicator oriented toward the operator's left. With the rib, pleural line, and overlying serratus anterior and latissimus dorsi muscles visualized, local infiltration of the skin and subcutaneous tissue will be applied by 2-3ml of lidocaine 2%. Then, using ultrasound guidance, A 38-mm 22-gauge regional block needle will be advanced in-plane at an angle of approximately 45 degrees towards the fifth rib. The expecting depth for this block is 1-4 cm. After aspiration, injection 30ml local anesthetic mixture will be injected anteriorly to the rib and deep to the serratus anterior muscle.

"Induction of general anaesthesia will be performed using a regimen of IV 2 μg/kg fentanyl and propofol IV 2 mg /kg. Tracheal intubation will be facilitated using 0.5 mg/kg IV of rocuronium.~Anaesthesia will be maintained with inhaled sevoflurane 2-2.5% in oxygen enriched air (FiO2=0.5). Maintenance doses of rocuronium 0.1 m\\kg will be provided every 30 minutes.~The residual neuromuscular blockade will be reversed using neostigmine (0.05 mg/kg) and atropine (0.02 mg/kg), and extubation will be performed after complete recovery of the airway reflexes."

30 ml bupivacaine 0.25% + 1 ml ketamine (50mg) in Serratus Anterior Plane Block.

30 ml bupivacaine 0.25% + 1 ml neostigmine (500 μg)in Serratus Anterior Plane Block.

30 ml bupivacaine 0.25% + 1 ml normal saline in Serratus Anterior Plane Block.