Malnutrition is a common comorbidity in patients undergoing thoracic surgery. Furthermore, chronic diseases, polypharmacy, low nutrient intake, reduced appetite, and psychological factors-all frequently observed in geriatric patients-serve as risk factors for the development of nutritional deficiencies. Consequently, it is crucial to address the issue of malnutrition in geriatric patients-who often present with these risk factors-and to ensure that a nutritional status assessment is performed prior to thoracic surgery. While numerous screening tools are currently available to assess nutritional status in the elderly, there is no established "gold standard." Although it has been suggested that these nutritional screening tools can serve as prognostic indicators for geriatric surgical patients, the relationship between these tools and postoperative outcomes-such as pain, complications, and length of hospital stay-has not yet been fully evaluated in geriatric patients undergoing lung resection. This study aims to determine the relationship between preoperative nutritional status and postoperative outcomes in patients undergoing lung resection-an area lacking sufficient literature-and to investigate whether preoperative nutritional support can reduce postoperative complications in this patient population.Patients will undergo preoperative assessment, and data regarding those meeting inclusion criteria will be recorded. This includes routine blood tests, age, height, body weight, BMI, gender, diagnoses, ASA and ARISCAT scores, the surgery performed, durations of surgery/anesthesia/one-lung ventilation, intraoperative fluids and IV agents administered, fluid balance, any complications arising during the procedure or postoperative follow-up (up to discharge), Visual Analog Scale (VAS) scores at postoperative hours 1, 2, 4, 8, 16, and 24, Charlson Comorbidity Index, Clinical Frailty Scale (CFS), and nutritional status (GNRI, NRS-2002, PNI, MNA-SF).
* Inclusion criteria: Patients undergoing elective thoracic surgery; patients undergoing lung resection via thoracotomy; patients who have provided informed consent; patients over 65 years of age; patients assessed as ASA class 1, 2, or 3; patients with a body mass index (BMI) between 18 and 35.
* Exclusion criteria: Patients with ASA class IV or higher; patients scheduled for emergency surgery; patients under 65 years of age; patients with a history of prior thoracic surgery; patients in GOLD groups 3 or 4; patients with systemic inflammatory disease; patients with preoperative chronic pain who regularly use anti-inflammatories/analgesics; patients with a history of pulmonary thromboembolism (PTE).