Analgesic Effect of Infraspinatus-teres Minor Block for Pre-emptive Analgesia in Patients Undergoing Shoulder Surgeries.

To compare between infraspinatus-teres minor versus control group (GA):

• To measure analgesic parameters including: the total amount of rescue analgesic consumption (morphine) in the first 24 hours post-operatively in each group, duration of analgesia, and total amount of intraoperative fentanyl consumption and
• To assess pain score by using numerical rate scale (NRS) at rest (static) and during passive or active movement of shoulder joint (dynamic).
• To assess discharge time from post anesthesia care unit (PACU).
• To assess side effects of systemic opioids (constipation, itching, dizziness, nausea and vomiting) and complications of infraspinatus-tere minor block.
• Patients' satisfaction: The patients will be asked to rate the overall degree of satisfaction of the analgesia by using a 5-points Likert-like verbal scale (1 = very dissatisfied analgesia, 2 = dissatisfied analgesia, and 3 = neutral, 4=satisfied analgesia, and 5=very satisfied analgesia).

Inclusion criteria

• • Patients' acceptance.

• Age: Adults aged 21-65 years old.
• BMI: 25-30 kg/m2
• Sex: both sexes (males or females).
• Patients undergoing unilateral shoulder surgey under general anesthesia.
• ASA (American Society of Anesthesiologists) physical status classification I to II.
• Duration of the surgery < 3hours.

Exclusion criteria

• • Patients with contraindications to regional anesthesia (e.g. local or systemic infections, or severe neurological or muscular or bleeding disorders or patient on anticoagulant).

• Allergy to study medications: bupivacaine or dexamethasone, or dexmedetomidine
• Patients with severe cardiovascular, respiratory, renal, or hepatic diseases, uncontrolled diabetes , or those undergoing chronic opioid therapy.
• Psychiatric disorders that hinder informed consent or study participation.
• history of neurological diseases or conditions that would affect the efficacy of nerve blocks (e.g., neuropathy, spinal cord injury, or history of severe muscle weakness).
• Patients with nerve injury or disease around the shoulder joint, including thoracic outlet syndrome, Multiple sclerosis, cervical disc disease with ipsilateral radiculopathy, or patients with abnormal sensory or motor function of the upper limb.