Comparison of IV Analgesia Protocols After the Regional Block's Effect Diminishes in Thoracic Surgery

The purpose of this study is to compare the effectiveness of three different intravenous (IV) patient-controlled analgesia (PCA) regimens-Fentanyl, Tramadol, and Ibuprofen-in managing postoperative pain and respiratory performance in patients undergoing Video-Assisted Thoracoscopic Surgery (VATS). While regional blocks like Erector Spinae Plane (ESP) block provide effective early analgesia, their effect typically diminishes after 8-12 hours, leading to potential 'rebound pain.' This study specifically investigates the period following the duration of the regional block's action. The primary goal is to evaluate which IV PCA protocol better controls pain (Visual Analog Scale scores) and supports better respiratory performance (measured by incentive spirometry) during the first 72 hours post-surgery

Inclusion Criteria: 1. \- Patients aged 18 to 80 years. 2. \- ASA (American Society of Anesthesiologists) Physical Status Score of I-III. 3. \- Body Mass Index (BMI) between 18 and 35 kg/m². 4. \- Undergoing elective thoracic surgery via Video-Assisted Thoracoscopic Surgery (VATS). 5. \- Voluntary participation confirmed by signing the written Informed Consent Form. Exclusion Criteria: 1. \- Age below 18 or above 80 years. 2. \- Advanced organ failure (e.g., severe hepatic or renal impairment). 3. \- ASA physical status \> III. 4. \- History of chronic pain treatment or long-term opioid use. 5. \- BMI \< 18 kg/m² or \> 35 kg/m². 6. \- Pregnancy or breastfeeding. 7. \- Limited cooperation due to dementia or uncontrolled psychiatric disorders. 8. \- Communication barriers (inability to communicate in the native language). 9. \- History of substance or drug abuse. 10. \- Known allergy or contraindication to the study drugs (Fentanyl, Tramadol, or Ibuprofen). 11. \- Contraindication to regional block placement (e.g., infection at the injection site).