Comparison of the Anaesthetic Gases in Maintainance of General Anaesthesia in Paediatrics
Condition: Paediatrics; General Anaesthesia
Study type: Interventional
Phase: Phase 1/Phase 2

Summary: 
      Desflurane and Sevoflurane are one of the modern inhalational anaesthetic agents currently in
      use in anaesthetic practice. The properties of desflurane that has low blood gas solubility
      coefficient of 0.47 compared to sevoflurane (0.68) made it more advantageous when used with
      supraglottic airway in maintaining general anaesthesia in paediatrics . It ensures rapid
      onset and offset of anaesthesia. Rapid recovery profiles especially among pediatric
      populations is to ensure less complications associated with prolonged recovery of anaesthesia
      upon emergence from anaesthesia. Nevertherless, desflurane has its drawback which is it can
      cause airway irritability related to its pungency. Hence, it is not used as an induction
      anaesthetic agent in paediatrics. This study was done to evaluate the effectiveness of
      desflurane in comparison to sevoflurane in maintaining spontaneous general anaesthesia in
      paediatrics population using Ambu AuraGain .
    

Detailed description: 
      Research design:

        1. Double blinded , randomised controlled trial.

        2. Involving paediatrics patients underwent elective surgeries requiring general
           anaesthesia in Hospital Universiti Sains Malaysia, Kubang Kerian.

        3. The duration of the study is 24 months.

      METHODOLOGY

        1. After Approval from the Ethics Committee of University Sains Malaysia (USM), verbal and
           written consent will be taken from the patient's parent(s), 1 day prior of the surgery
           during pre-operative assessment in ward. All medical information of the patient will be
           kept confidential.

        2. The study will be conducted to patient age 3 years to 12 years old, with body weight
           between 10-30kg after excluding patient who has a upper respiratory tract infection or
           known susceptible to malignant hyperthermia.

        3. Patients who fulfil the inclusion and exclusion criteria during pre-operative assessment
           will be randomized into two group using computer generated randomization. The number
           generated will be placed in the envelope and allocation will be done on the day of the
           study prior to anaesthesia : S group (sevoflurane maintainance anaesthesia) = 40 and D
           group ( desflurane maintainance anaesthesia ) = 40.

        4. Allocation concealment is being applied in this study to prevent selection bias by
           concealing the allocation sequence until the moment of assessing.

        5. Participants and the researcher( whom assessing the outcomes ) are blinded during
           intervention ( double blinded ), where as the anesthetist in charge ( operator ) is not
           blinded.

        6. Standard monitoring with non invasive blood pressure , electrocardiography
           capnography,and peripheral oxygen saturation ( SPO2) will be used.

        7. Induction of anaesthesia with intravenous fentanyl 2mcg per kg, intravenous propofol of
           2mg/kg and 3-4vol% of sevoflurane under 100% O2 mask ventilation.

        8. The AmbuAuraGain will be used, with standard insertion technique.

        9. After induction of anaesthesia, inhalation agent will be switch immediately according to
           group allocation for maintainance of anaesthesia.

       10. Anaesthesia will be maintained using SEVOFLURANE at MAC of 1.2 to 1.5 for the S group
           and DESFLURANE at MAC 1.2 to 1.5 for the D group with mixture of oxygen/air mixture for
           both groups.

       11. IV Paracetamol 15mg/kg and IV Fentanyl 0.5mcg/kg will be given as intraoperative
           analgesia.

       12. Short acting opiod : IV fentanyl 0.5mcg per kg can be given as rescue analgesia.

       13. At the end of surgery (the last suture put), the inhalational agents will be tapered
           down and discontinued, 100% oxygen with 6l/min was administered. The Ambu®AuraGain™ will
           be removed in the operating room once the child is fully awake (i.e: regular breathing,
           good tidal volume of 6-8ml/kg, gag reflex, grimacing and purposeful movements of the
           extremities).

       14. The child then will be monitored in operating theatre recovery area until the modified
           Aldrete score reached 8.

       15. Perioperative events in the operating room will be recorded by a blinded investigator.
           Any adverse events and emergence agitation during recovery will be recorded by a blinded
           nurse until patient is discharged to ward.

       16. The first outcome of this study will be the intraoperative hemodynamics during
           maintainance of anaesthesia.

       17. Baseline hemodynamic (blood pressure, heart rate, mean arterial pressure) of the patient
           during pre-intubation will be taken. After successful intubation, patient haemodynamics
           will be recorded at 10 minutes interval until 60 minutes and also during pre extubation
           and post extubation.

       18. Second outcome will be the time of emergence ( the time interval from gas being off to
           patient awake,i.e: spontaneous eyes opening) , emergence agitation in recovery area, and
           the respiratory adverse events that occurs during maintainance of anaesthesia and
           emergence .

       19. The respiratory events which will be recorded are, (ie: breath holding , bronchospasm,
           coughing, laryngospasm, copious secretions ( which required suctioning), desaturations (
           SpO2 < than 90% ).

      SAMPLE SIZE ESTIMATION

      Objective 1 : hemodynamic changes ( heart rate)

      To estimate the sample size for our study we utilized the G.Power sample size calculator
      software version 3.1 - Anova : repeated measures . Parametres used in the sample size are :

      Effect size f : 0.39 ( for heart rate , Akhtam A. Shoukry et al,2016)

        -  0.05 power : 0.80 number of groups: 2 number of measurements: 10 Standard Deviation
           within each group : 8.97 Mean group 1 : 68.04, mean group 2 : 75.09

      Sample size is 32 per group. Estimated sample size with 10% drop out rate : 70

      Objective 2 : Emergence time

      To estimate the sample size for our study we utilized the PS: Power and Sample Size
      Calculations software,version 3.0. We applied the independent t-test. Parametres used in the
      sample size are :

      Standard Deviation = 3.9 ( Demirbilek,2004) Mean difference = 3.8 ( expert opinion ) = 0.05
      power = 0.80 m = 1 Sample size is 18 per group. Estimated sample size with 10% drop out rate
      :40

      Objective 3 : Coughing on emergence

      To estimate the sample size for our study, we utilized the PS: Power and Sample Size
      Calculations software,version 3.0. We applied the Dichotomous independent , two
      proportions,uncorrected chi-square test.

      Parametres used in the sample size calculations are :

      = 0.05, power = 0.80, m = 1, P0 = 0.49 ( proportion of desflurane among patients who did not
      cough), Paul at al,2010). P1 = 0.8 ( proportion of desflurane among patients who did cough,)
      expert opinion ).

      Sample size is 36 per group.

      Estimated sample size with 10% drop out rate : 80

      STATISTICAL DATA ANALYSIS

      OBJECTIVE 1:

      numerical data will be analysed using ANOVA: repeated measures.

      OBJECTIVE 2:

      Numerical data will be analysed using independent t test.

      OBJECTIVE 3:

      Categorical data will be analysed using uncorrected chi square test.
    

Intervention name(s): DESFLURANE AND SEVOFLURANE
Intervention type(s): Drug
Intervention description(s): COMPARING THE EFFICACY IN MAINTAINANCE OF SPONTANEOUS GENERAL ANAESTHESIA USING AMBU AURA GAIN IN PEDIATRIC PATIENTS
Other intervention name(s): Suprane and Sevoflurane
Intervention MeSH terms: Sevoflurane; Desflurane
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Supportive Care
Keywords: paediatrics; spontaneous general anaesthesia