Propofol for Pediatric Tracheal Intubation With Deep Anesthesia During Sevoflurane Induction
Condition: Anesthesia Intubation Complication
Study type: Interventional
Phase: Phase 4

Summary: 
      The purpose of this study is to determine the amount of propofol required to achieve 50% of
      patients obtaining a perfect ("excellent") intubation score of 5 on the Steyn modification of
      the Helbo-Hansen Intubation Score, when placing a tracheal tube in children 1-6 years and
      6-12 years (division of age groups at 6th birthday) of age, under a specific induction and
      ventilation sequence as specified in this study design.
    

Detailed description: 
      The practice of tracheal intubation of children without neuromuscular blockade (TIWNB) is
      widespread in pediatric anesthesia practices. There are several different methods reported
      for TIWNB, most of which involve administration of an inhaled anesthetic in combination with
      an intravenous adjunctive medication. The technique of administering propofol IV, immediately
      after IV placement, after a sevoflurane induction is perhaps the most popular method for
      pediatric TIWNB in the United States and worldwide (personal communication, and personal
      practice of this technique). At the time this study was proposed, nobody had studied this
      technique, and therefore nobody had quantified the amount of propofol needed in this context,
      or considered that the amount may differ according to the time sevoflurane has been
      administered at the moment propofol is given. This study divides patients into two age
      categories, with the first age group starting at the 1 year birthday and going up to the 6th
      year birthday, and the second age group going from the 6th year birthday up to the 12th
      birthday. The study also divides participants according to time that they have received
      sevoflurane from the start of anesthetic induction until intravenous access is achieved and
      propofol immediately administered. That amount of time varies in clinical practice due to
      variable difficulty obtaining pediatric intravenous access, and the amount of propofol may
      vary according to the amount of sevoflurane administered (time administered) because depth of
      anesthesia will increase with increasing duration of sevoflurane administration. The purpose
      of this study is to determine for both age groups the amount of propofol required to achieve
      50% of patients obtaining a perfect intubation score of 5 on the Steyn modification of the
      Helbo-Hansen Intubation Score (HH Score), when placing a tracheal tube after various time
      periods of administration of sevoflurane. The 3 different time windows for sevoflurane
      administration prior to the propofol bolus will be 2-4 minutes, 4-6 minutes, and 6-8 minutes,
      starting the time clock at the start of anesthetic induction and ending at the moment the
      propofol is given. The study therefore has 6 separate groups (2 age groups x 3 time period
      groups) each of which utilizes a Dixon's Up and Down Method, moving up or down on the amount
      of propofol administered according to the result of the previous patient in each group (HH
      Score of 5 labeled "excellent intubation" indicates allocation of predetermined (0.3 mg/kg)
      incrementally smaller amount of propofol and >5 labeled as "not-excellent intubation" an
      increase of 0.3 mg/kg of propofol. Linear regression will be used for each of the 6 groups to
      determine the amount of propofol required to achieve 50% perfect intubation, with 95%
      confidence intervals also calculated.
    

Intervention name(s): propofol
Intervention type(s): Drug
Intervention description(s): Initial dose: Propofol 2 mg/kg, then dose changes separately based on the last subject in the same age group and sevo time range
Intervention MeSH terms: Propofol
Intervention model: Single Group Assignment
Intervention model description: This is a single study with 6 parallel groups as noted in the description. With Dixon's Up and Down Method for determining a 50th percentile of a dichotomous outcome, the number of patients required is not known prior to starting a study. Data from Paul and Fisher demonstrated that 6 "crossovers" (change in the dichotomous outcome from one patient to another, indicating change from increasing the dose of the study drug to decreasing it, or visa-versa). When choosing a meaningful starting point near the 50th percentile, the number required is typically 15-20 patients. With 6 study groups, the estimated number of patients required would be 90-120. Please Note: This is not a study where one can perform a power analysis and determine a required N.
Masking: None (Open Label)
Primary purpose: Health Services Research
Keywords: intubation of children without neuromuscular blockade