Intranasal insulin for prevention of emergence agitation after endoscopic nasal surgery in adults: a randomized, double-blind, placebo-controlled, parallel-group trial

INTERVENTION: Insulin low‐dose group:Intranasal recombinant human insulin 10 U administered to both nostrils using the study nasal spray device.;Insulin high‐dose group:Intranasal recombinant human insulin 20 U administered to both nostrils using the study nasal spray device.;Control group:Placebo (0.9% saline) administered intranasally using an identical nasal spray device, with volume matched to the insulin groups.; CONDITION: Emergence agitation after endoscopic nasal surgery in adults PRIMARY OUTCOME: Incidence of emergence agitation; SECONDARY OUTCOME: Postoperative delirium within 24 hours;Agitation in PACU and peak Riker SAS score;Sleep disturbance on the first postoperative night;Nasal irritation symptoms and other adverse events;Blood glucose and hypoglycemic events;Postoperative pain scores;Postoperative anxiety within 24 hours;Serum IL‐6 and TNF‐alpha levels;Postoperative cognitive decline; INCLUSION CRITERIA: 1. Age >= 18 years old, gender not restricted; 2. Planned for elective endoscopic nasal surgery, such as radical treatment for chronic sinusitis with nasal polyps, nasal septum correction combined with sinus opening, with an estimated operation duration of 1‐3 hours; 3. ASA classification I‐III; 4. Preoperative MMSE score >= 24 points; 5. Diabetic patients with fasting blood glucose <= 13.9 mmol/L and no insulin use before the operation; 6. The patient or legal representative signs the informed consent form and can cooperate to complete the postoperative assessment.