Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12619001434189
Ethics application status
Approved
Date submitted
2/09/2019
Date registered
16/10/2019
Date last updated
15/03/2022
Date data sharing statement initially provided
16/10/2019
Date results information initially provided
15/03/2022
Type of registration
Prospectively registered

Titles & IDs
Public title
A study in children undergoing elective general anaesthesia to compare the effectiveness of two different maneouvres to re-open collapsed lungs using a continuous forced oscillation technique (FOT) system.
Scientific title
OASIS: Oscillation mechanics and sustained inflation study using forced oscillation technique measurements of children under general anaesthesia to compare the effectiveness of two different recruitment maneouvres.
Secondary ID [1] 299019 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Ventilation in children undergoing general anaesthesia 314026 0
Condition category
Condition code
Anaesthesiology 312413 312413 0 0
Anaesthetics

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Intervention materials:
This study involves the use of a continuous FOT (forced oscilliation technique system) to measure lung mechanics in children receiving one of four inflation techniques:
1. Sustained inflation via a Laryngeal mask airway device (LMA)
2. Repeated inflations via an LMA
3. Sustained inflation via tracheal tube (TT)
4. Repeated inflations via TT
The type of airway device will be determined by the attending anaesthetist regardless of the study. Manual breaths will be from the bag and mask and sustained inflation will be from the machine.
Procedures used: Once the interface is in place and ventilation has started, children will be randomised to receive either 20 slow manual breaths with PIP=40cmH20 and PEEP = 15 cmH20 pr one sustained manual inflation of 40 cmH20 for 20 seconds. Lung mechanics will be assessed using a continuous FOT system.
Who will deliver the intervention: the intervention will be delivered by the attending paediatric anaesthetist
Mode of delivery: in theatre
Number of times: once
Location: Perth Children's Hospital surgical theatres

Lung mechanics will be assessed using FOT. Measurements will be carried out following the international guidelines and recommendations set by the American Thoracic Society and the European Respiratory Society.
Low amplitude sinusoidal pressure oscillations (2 cmH2O peak-to-peak) at 5 Hz are generated by a loudspeaker connected to the inspiratory line of the mechanical ventilator and applied at the inlet of the tracheal tube. The rear of the loudspeaker is enclosed in a chamber and connected to the inspiratory outlet of the ventilator to equilibrate the positive pressures on both sides of the loudspeaker membrane. Pressure and flow are measured at the airway opening using a pressure transducer and a mesh-type heated pneumotachograph connected with a differential pressure transducer. Signals are sampled at 200 Hz and exported on a personal computer for offline analysis.
FOT Measurements will be performed following the induction of anaesthesia prior to the start of surgery before and after the randomised recruitment manoeuvre as well as at the end of surgery prior to emergence of anaesthesia. Each measurement will take 1 to 2 minutes.
Intervention code [1] 315285 0
Diagnosis / Prognosis
Comparator / control treatment
Sustained inflation via a Laryngeal mask airway device (LMA)
Control group
Active

Outcomes
Primary outcome [1] 321064 0
The primary outcome is the magnitude of change in reactance (Xrs) measurements - the after measurement minus the before measurement (using the FOT data alongside the clinical observations). Comparisons will be made between different recruitment manoeuvres in mechanically ventilated children undergoing general anaesthesia.
Timepoint [1] 321064 0
FOT Measurements will be performed following the induction of anaesthesia prior to the start of surgery before and after the randomised recruitment manoeuvre as well as at the end of surgery prior to emergence of anaesthesia.
Secondary outcome [1] 373856 0
The secondary outcome will be to examine the change in resistance (Rrs) measurements during the same recruitment manoeuvres (using the FOT data alongside the clinical observations).
Timepoint [1] 373856 0
FOT Measurements will be performed following the induction of anaesthesia prior to the start of surgery before and after the randomised recruitment manoeuvre as well as at the end of surgery prior to emergence of anaesthesia.

Eligibility
Key inclusion criteria
Children undergoing surgery with general anaesthesia through either laryngeal mask or tracheal tube.
Minimum age
2 Years
Maximum age
16 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Children with a known difficult airway or thoracic malformation
Children with a known major lung and/or cardiopulmonary disease:
· Uncorrected congenital heart disease
· Primary/secondary pulmonary hypertension
· Cardiac/thoracic malformations/tumours
· Structural lung changes
· Uncontrolled asthma
· Cystic Fibrosis
The above list is a non-exhaustive list. Any other less common cardiopulmonary conditions will be assessed by the anaesthetist in charge and accounted for in the exclusion criteria list.

Study design
Purpose of the study
Diagnosis
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Sealed opaque envelopes
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated block randomisation
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Other
Other design features
Participants will be assigned to one of two inflation techniques.
The type of airway device will be decided upon by the treating anaesthetist as per normal clinical practice.
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Analysis plan and sample size
The study design is a two way Anova. Factor 1 is the recruitment strategy with two levels, and factor 2 is the administering method with two levels. We use the measurements for Xrs and Rrs from (Eur Respir J 2013; 42: 1513–1523). To detect a difference of 0.5 in Xrs with a power of 0.98 requires a sample size of 19 per group, or a total sample size of 76. 0.5 is the assumed mean change in Xrs in the recruitment arms as well as administering methods. The assumed standard deviation was 0.5 for both. 2 patients will be added to each group to loss of data, therefore requiring a total group size of 21 and a total sample size of 84.

Loss of data is standard for in theatre research measurements due to the complex theatre environment with many last minute changes to the surgical lists due to changing patient and surgical priorities, which may include changing times or days of surgery, type of surgery, which may render a patient non-eligible or move the patient to a time or date on which no study staff is available. A lesser amount of data loss (around 10%) is attributable to technical problems or other clinical issues during or prior to measurements which interfere with data collection.)

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
4/11/2019
Actual
13/02/2020
Date of last participant enrolment
Anticipated
19/04/2021
Actual
9/03/2022
Date of last data collection
Anticipated
20/04/2021
Actual
9/03/2022
Sample size
Target
84
Accrual to date
Final
84
Recruitment in Australia
Recruitment state(s)
WA
Recruitment hospital [1] 14545 0
Perth Children's Hospital - Nedlands
Recruitment postcode(s) [1] 27557 0
6009 - Nedlands

Funding & Sponsors
Funding source category [1] 303552 0
Charities/Societies/Foundations
Name [1] 303552 0
Perth Children's Hospital Foundation
Country [1] 303552 0
Australia
Funding source category [2] 308325 0
Charities/Societies/Foundations
Name [2] 308325 0
Australian and New Zealand College of Anaestetists
Country [2] 308325 0
Australia
Primary sponsor type
Hospital
Name
Perth Children's Hospital
Address
Perth Children's Hospital
15 Hospital Avenue
Nedlands
WA 6009
Country
Australia
Secondary sponsor category [1] 303628 0
None
Name [1] 303628 0
Address [1] 303628 0
Country [1] 303628 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 304083 0
Child and Adolescent Health Service Ethics Committee
Ethics committee address [1] 304083 0
Level 5,
Perth Children’s Hospital
15 Hospital Avenue
Nedlands
WA 6009
Ethics committee country [1] 304083 0
Australia
Date submitted for ethics approval [1] 304083 0
21/05/2019
Approval date [1] 304083 0
06/08/2019
Ethics approval number [1] 304083 0
RGS0000003274

Summary
Brief summary
The OASIS project is a single-centred,randomised, prospective study of 85 children. Lung mechanics will be assessed using continuous forced oscillation technique (FOT).

The aims are, in children undergoing general anaesthesia, to compare the effect on forced oscillations mechanics of:
1) two different recruitment strategies: repeated inflations vs. one sustained inflation to a high-pressure level,
2) administering them through a laryngeal mask vs a cuffed tracheal tube.

We hypothesise that:
(1) One sustained inflation is more effective than multiple manual breaths with high levels of inspiratory and expiratory pressure in recruiting the lung
(2) Both recruitment strategies (sustained inflation or multiple manual breaths) are less effective when applied via laryngeal mask compared with an endotracheal tube.

The results of this study will help paediatric anaesthetists to formulate new evidence-based guidelines and policies to optimize the ventilation strategy in children undergoing general anaesthesia. Additionally, successful implementation of continuous forced oscillation technique (FOT) measurements (assessment of respiratory mechanics) in the setting of different airway devices has the potential to change routine clinical practice by allowing anaesthetists to adapt ventilation to rapid changes in mechanics during anaesthesia which are particularly pronounced in young children.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 95758 0
Prof Britta Regli-von Ungern-Sternberg
Address 95758 0
Perth Children's Hospital
15 Hospital Avenue
Nedlands
WA 6009
Country 95758 0
Australia
Phone 95758 0
+61420790101
Fax 95758 0
Email 95758 0
Britta.Regli-VonUngern@health.wa.gov.au
Contact person for public queries
Name 95759 0
Prof Britta Regli-von Ungern-Sternberg
Address 95759 0
Perth Children's Hospital
15 Hospital Avenue
Nedlands
WA 6009
Country 95759 0
Australia
Phone 95759 0
+61420790101
Fax 95759 0
Email 95759 0
Britta.Regli-VonUngern@health.wa.gov.au
Contact person for scientific queries
Name 95760 0
Prof Britta Regli-von Ungern-Sternberg
Address 95760 0
Perth Children's Hospital
15 Hospital Avenue
Nedlands
WA 6009
Country 95760 0
Australia
Phone 95760 0
+61420790101
Fax 95760 0
Email 95760 0
Britta.Regli-VonUngern@health.wa.gov.au

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
Investigators for the study are still deciding upon how to proceed with this.


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.