Effect of Intrathecal Bupivacaine Temperature Variation on Prophylaxis of Shivering in Urologic Patients Undergoing Spinal Anesthesia

Inclusion Criteria: * 1\. Adult patients scheduled for urological procedures under spinal anaesthesia. 2. Patient age ranges from 18 to 60 years. 3. American Society of Anesthesiologists (ASA) physical status class I or II. Exclusion Criteria: * 1\. Patient's refusal of regional block. 2. Patients with neurological disorders, increased intracranial pressure, convulsive disorders, autonomic neuropathies, psychological disorders, or those lacking cooperation. 3\. Patients with anatomical abnormalities, skin lesions, wounds, or infection at the site of injection, or general infection. 4\. Patients with bleeding disorders defined as (INR\>1.4) and/or (platelet count \< 100,000/µL). 5\. Patients with known hypersensitivity to any of the study drugs. 6. Patients with renal impairment. 7. Patients with hepatic disease e.g. severe liver cell failure, or hepatic malignancy, or hepatic enlargement. 8\. Patients with failed, or partial spinal block.