Pre-emptive analgesia of intrapleural and serratus plane blocks for breast surgeries: A randomized prospective clinical trial

30 patients in each group will be randomized using closed envelops and a computer generated random numbers into 2 groups (30 patients each). Each block will be performed just after induction of anesthesia. Group I (intrapleural block): While the patient is in the supine position, the block will be performed using number 18 Touhy needle at the 5th intercostal space in the anterior midaxillary line. The needle will be introduced while the patient is disconnected from the ventilator to avoid lung injury or pneumothorax. Loss of resistance technique will be used to identify the intrapleural space. After negative aspiration test 40 ml of 0.25% levobupivacaine will be injected in the intrapleural space. Group II (serratus plane block): The patients will be in the supine position, and the ultrasound probe will be in the sagital plane over the mid clavicular region , then we will go inferiorly and laterally till we identify the 5th rib in the mid axillary line to identify the latissimus dorsi, teres major and serratus muscles. 22G needle will be introduced in-plane in relation to the ultrasound probe, then 0.4 ml/kg levobupivacaine 0.25% will be injected in the potential space superficial to the serratus anterior muscle. In the intra-operative period; if signs of sympathetic stimulation (increase in heart rate and mean arterial blood pressure more than 20 % from the baseline values despite adequate level of anesthesia) treated with iv bolus doses of fentanyl 0.5 micogram /Kg. In the post-operative period: Visual Analogue Score (VAS). 0 = no pain, to 10 = the most severe pain, 0-3 = mild pain , 4-6 = moderate pain, >6 = severe pain Patients with moderate or severe pain will receive diclofenac sodium 75 mg intramuscular injection. (VAS) will be recorded at 1, 2, 4, 8, 12, 18, and 24 hours post-operatively.