Airway Management, General Anesthesia, LMA, Pediatric Anesthesia
Conditions
Keywords
Alfentanil, Propofol, Pediatric Anesthesia, LMA, Dixon Method, Effective dose
Brief summary
This study uses a prospective, up-and-down sequential allocation method to determine the median effective dose (ED50) and 95% effective dose (ED95) of alfentanil combined with propofol for successful laryngeal mask airway (LMA) insertion in children aged 7-12 undergoing elective day surgery.
Detailed description
Laryngeal mask airway (LMA) insertion is a common practice in pediatric day surgery. While it is less invasive than endotracheal intubation, children exhibit high airway reactivity, requiring an optimal depth of anesthesia to suppress airway reflexes. Alfentanil is an opioid with a rapid onset and short duration of action, making it potentially ideal for LMA insertion. However, current dosage recommendations for alfentanil are often extrapolated from tracheal intubation studies, which may lead to overdosage, respiratory depression, or delayed recovery in children. This study aims to determine the precise effective dose (ED50 and ED95) of alfentanil when combined with a fixed dose of propofol for smooth LMA insertion in children.
Interventions
DRUGAlfentanil
All patients receive 2.5 mg/kg propofol injected over 30 seconds. Alfentanil is administered 1 minute prior to propofol. The dose is adjusted by steps of 2 µg/kg based on the previous patient's response (successful insertion = decrease dose; failed insertion = increase dose).
Sponsors
Zhongshan Ophthalmic Center, Sun Yat-sen University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
7 Years to 12 Years
Healthy volunteers
No
Inclusion criteria
* Aged 7 to 12 years * Undergoing elective day surgery * ASA physical status I-II * Body Mass Index (BMI) between 14 and 24 kg/m² * Accompanied by a fully capable guardian within 24 hours after discharge
Exclusion criteria
* Allergy to opioids * Unresolved upper respiratory tract infection within the past 1 week * Abnormal heart, lung, liver, or kidney function, or metabolic diseases * Airway anatomical abnormalities (e.g., micrognathia, laryngomalacia, macroglossia) or OSAHS (Obstructive Sleep Apnea-Hypopnea Syndrome) * Use of analgesics, sedatives, or other psychotropic drugs within the past 2 weeks * Refusal to sign the informed consent form
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Success of LMA insertion | Intraoperative (During LMA insertion procedure) | Assessed by the absence of body movement, coughing, breath-holding, severe hemodynamic changes, or insertion difficulty. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Time required for LMA insertion | Intraoperative (from LMA pick-up to successful placement). | The time (in seconds) from picking up the LMA to the first successful breath as confirmed by capnography. |
| Number of LMA insertion attempts | Intraoperative (during the anesthesia induction phase). | The total number of attempts required to successfully place the LMA. An attempt is defined as the introduction of the LMA into the patient's mouth. |
| Airway Responses | During and up to 1 minute post-insertion | Incidence and severity of body movement, cough, breath-holding, and laryngospasm. |
| Changes in Heart Rate (HR) | From baseline (pre-induction) up to 1 minute after LMA insertion. | Evaluation of heart rate (beats per minute) to assess hemodynamic stability at four time points: T0 (baseline), T1 (post-induction), T2 (immediate post-insertion), and T3 (1 min post-insertion). |
| Changes in Mean Arterial Pressure (MAP) | From baseline (pre-induction) up to 1 minute after LMA insertion. | Evaluation of mean arterial pressure (mmHg) to assess hemodynamic stability at four time points: T0 (baseline), T1 (post-induction), T2 (immediate post-insertion), and T3 (1 min post-insertion). |
| Awakening time | From end of surgery up to 1 hour. | The interval from the discontinuation of anesthetic agents to the moment the patient follows simple commands or opens eyes. |
| Post-Anesthesia Care Unit (PACU) discharge time | Up to PACU discharge(assessed up to 4 hours after surgery completion). | The duration (in minutes) from arrival in the PACU until the patient meets discharge criteria. |
| Postoperative Adverse Events | At 6 hours and 24 hours post-operation | Incidence of PONV (postoperative nausea and vomiting), sore throat, and hoarseness. |
Countries
China
Contacts
CONTACTRui Zhang, M.D.
Outcome results
None listed