Assessment of Reintubation Risk Using Multiple Parameters in Postoperative Intensive Care Unit Patients

Inclusion Criteria: Adult patients aged 18 years and older Patients requiring postoperative intensive care follow-up after major surgery, including abdominal, vascular, orthopedic, or ear, nose, throat, head and neck surgery Patients extubated in the operating room and admitted to the intensive care unit with spontaneous breathing Patients without any clinical condition preventing the planned measurements within the first 0-2 hours after ICU admission (T0 and T1) Patients for whom written informed consent can be obtained from the patient or legally authorized representative Patients admitted to the intensive care unit within the specified study period after ethics committee approval and enrolled consecutively Exclusion Criteria: Patients younger than 18 years of age Patients who leave the operating room intubated or are admitted to the intensive care unit while intubated Patients with a tracheostomy Patients with a history of diaphragmatic paralysis Patients with a significant neuromuscular disease, such as ALS, myasthenia gravis, or similar conditions Patients with conditions that significantly prevent ultrasound measurements, including marked subcutaneous emphysema, large dressings or bandages covering the measurement area, inability to access the measurement site due to drains or the surgical field, or inability to obtain technically adequate images Patients in whom the planned measurements cannot be performed due to clinical instability requiring emergency intubation immediately after ICU admission Patients from whom informed consent cannot be obtained, or patients or legally authorized representatives who refuse participation