Dexmedetomidine Nasal Spray on Postoperative Delirium in Elderly Thoracoscopic Lung Resection Patients

Time from End of Surgery to Tracheal Extubation (Minutes)

The time interval, measured in minutes, between the surgeon's confirmed end of surgery (defined as completion of final wound closure) and complete removal of the tracheal tube from the patient's airway, documented via the official electronic anesthesia record.

Time frame: From the immediate end of surgery until successful tracheal extubation, assessed up to 2 hours after surgery completion (prior to discharge from the Post-Anesthesia Care Unit [PACU]).

Duration of Post-Anesthesia Care Unit (PACU) Stay (Minutes)

The time interval, measured in minutes, between two standardized, timestamped endpoints: 1. Start point: The time of patient admission to the PACU, defined as the time when the patient is transferred into the PACU and connected to standard vital sign monitoring; 2. End point: The time of patient discharge from the PACU, defined as the time when the patient physically exits the PACU after meeting institutional discharge criteria. Data is prospectively documented in the official electronic anesthesia/PACU medical record.

Time frame: From patient admission to the PACU (immediately post-surgery) until PACU discharge, assessed up to 24 hours after PACU admission.

Incidence of adverse events

Incidence of adverse events following administration of the investigational product.

Time frame: From administration of the investigational product up to 7 days postoperatively.

Subjective sleep quality

Patient-reported subjective sleep quality, assessed daily using the 11-point Numerical Rating Scale (NRS, 0 = best sleep, 10 = worst sleep) on postoperative days 1-3.

Time frame: postoperative days 1 through 3

NRS pain score

Pain score will be assessed using the Numerical Rating Scale (NRS) before discharge from the post-anesthesia care unit (PACU) and daily on postoperative days 1-3. (0 = no pain, 1-3 = mild pain, 4-6 = moderate pain, 7-10 = severe pain)

Time frame: Before discharge from the PACU and on postoperative days 1 through 3.

The severity of postoperative delirium

Delirium severity will be assessed using the Memorial Delirium Assessment Scale (MDAS) in patients with positive delirium on postoperative days 1-3. The MDAS consists of 10 items with a total score of 30; the severity of delirium is defined as the maximum MDAS score obtained during postoperative days 1-3.

Time frame: postoperative days 1 through 3

Duration of delirium

The period commencing from the day delirium was first assessed as positive until delirium was assessed as negative or the patient was discharged.

Time frame: Time from delirium onset to resolution, assessed up to 7 days postoperatively.

Duration of Postoperative Hospital Stay (Days)

Defined as the total number of calendar days from the day of index surgery to the day of hospital discharge. Discharge is defined as the time when the patient is formally discharged and physically leaves the hospital facility, recorded in the electronic hospital medical record.

Time frame: From the day of surgery until formal hospital discharge, assessed up to 30 days after surgery.