This research protocol aims to investigate the 90% effective dose (ED90) of taiglididine for inhibiting laryngeal mask insertion response in elderly patients. It is a non-randomized controlled trial using a biased coin design up-down method (BCD-UDM). A total of 54 elderly patients aged 65-80 years with ASA I-III, BMI 18-30 kg/m², and suitable for urological surgery under general anesthesia with laryngeal mask insertion will be enrolled. The first patient receives an intravenous injection of 1 mg taiglididine, followed by propofol and rocuronium. Subsequent doses of taiglididine are adjusted dynamically based on the previous patient's response: increasing by 0.1 mg if the insertion response is positive, or using BCD-UDM (11% probability to decrease by 0.1 mg, 89% to remain) if negative. The primary efficacy endpoint is the occurrence of laryngeal mask insertion response, while secondary endpoints include adverse events, vital sign changes, insertion success rate, and various time intervals. Safety is evaluated by monitoring vital signs. Statistical analysis will use SPSS 25.0 and R software to calculate ED90 and 95% confidence intervals via probit regression and bootstrap method, with at least 45 valid patients required to complete the trial.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
TREATMENT
Masking
NONE
Enrollment
45
The first patient receives an intravenous injection of 1 mg taiglididine for anesthesia induction, followed by 1-2 mg/kg propofol. When the patient's bispectral index (BIS) drops below 60, eyelash reflex disappears, and MOAA/S score is 0, intravenous rocuronium 0.6 mg/kg is given, and a laryngeal mask is inserted by a senior anesthesiologist using a unified method 1 min later. From the second patient onward, the taiglididine dose is dynamically adjusted based on the previous patient's response to laryngeal mask insertion using BCD-UDM: if the previous patient shows a positive insertion response (positive response or MOAA/S ≥2 within 2 min after induction), the next patient's dose increases by 0.1 mg; if negative, a random number (1-95) generated by computer determines the dose: doses remain unchanged when the number is 6-95 (89% probability) and decrease by 0.1 mg when the number is 1-5 (11% probability). A collaborator not involved in result evaluation provides a sealed envelope with
Number of patients with positive laryngeal mask insertion response
If the patient has movement during laryngeal mask insertion, twitching at the corner of the mouth, coughing, frowning, tearing, laryngospasm, bispectral index not decreasing to below 60, an increase in heart rate or blood pressure of more than 20% of the baseline value within 2 minutes after laryngeal mask insertion, tachycardia (heart rate \>120 beats per minute), or hypertension (systolic blood pressure \>180 mmHg), and one of these occurs, it is determined as a positive laryngeal mask insertion reaction; otherwise, it is negative.
Time frame: Perioperative
Number of adverse reactions
Blood pressure elevation (systolic blood pressure/diastolic blood pressure \>20% baseline), hypotension (systolic blood pressure/diastolic blood pressure \<20% baseline or \<85/50 mmHg), bradycardia (heart rate \<50 bpm), tachycardia (heart rate \>100 bpm), hypoxemia (pulse oximetry \<92%), When 2 ml of propofol is injected, the patient is asked if there is any injection pain.
Time frame: Perioperative
Number of successful cases of laryngeal mask placement
Number of successful cases of laryngeal mask placement
Time frame: Perioperative
Adverse reactions such as pain, dizziness, headache, nausea and vomiting, sore throat, chills, choking, agitation, hoarseness of voice, and Intraoperative knowledge
The number of adverse reactions
Time frame: Perioperative
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