High flow nasal oxygen therapy has been widely used but guidelines as to the optimal starting flow rate and oxygen percentage are not available. Prolonged exposure to an inappropriately high oxygen concentration should be avoided as there is increasing evidence that the production of oxygen free radicals can lead to lung damage. This pilot dose finding study will determine the optimal flow rate and oxygen concentration using HFNO2 for patients with respiratory failure requiring low, medium or high oxygen concentration from conventional low flow devices. An assessment will also be made of comfort and compliance with HFNO2.
The study will recruit a total of between 180 and 270 patients across three hospital sites mainly from high dependence units. The patients recruited will be stratified into 3 groups according to their oxygen (O2) requirements at recruitment (low, medium and high). All recruited patients will then be given supplementary O2 using the Optiflow system. Patients from all three recruitment oxygen requirements (low, medium and high) will be randomised to 30 litres, 45 litres or 60 litres per minute with initial a fractional inspired O2 concentration(FiO2) of 0.90 (90% oxygen). The FiO2 is then decreased in 0.05 increments every 5 minutes and the minimum oxygen saturation recorded until it reaches 94%. End points: Minimal FiO2 required to maintain saturation above 94% for patients with low, medium and high recruitment oxygen requirements for 30 litres, 45 litres and 60 litres per minute. Use Kruskal Wallis to compare the median FiO2 requirements of those patients who recruited with low, medium and high O2 requirement. Obtain dose response curve 02 saturation against FiO2 for 3 different flow rates for each of the recruitment 02 requirements and use regression modelling to find best fit dose FiO2 response O2 saturation curves Patient satisfaction scores and number of patients unable to tolerate the three flow rates in each of the three starting groups and flow rates.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
NONE
High flow nasal oxygen delivery device 'Optiflow'
Queen Elizabeth University Hospital
Glasgow, United Kingdom
RECRUITINGMedian FiO2 (%) needed to be delivered via high flow therapy (Optiflow), at 3 different flow rates, to maintain an oxygen saturation ≥94 % and respiratory rate ≤30 in 3 groups of patients with acute respiratory failure
The median fraction inspired concentration ( FiO2) required to maintain an oxygen saturation ≥94 % and respiratory rate ≤30 in patients with respiratory failure using 'Optiflow' device at three different oxygen flow rates 30 litres 45 litres and 60 litres per minute flow within the three stratified groups of low, median and high oxygen requirements (at recruitment to the study).
Time frame: 75 minutes after start of study
Patient satisfaction scores
Comfort of new device when delivering oxygen with each oxygen flow rate: comfort, bloating, dry mouth, ability to hear and speak in comparison to conventional oxygen therapy
Time frame: 75 minutes after start of study
Number of patients unable to tolerate 'Optiflow' device
Failure to complete the 75 minutes with 'Optiflow' at three different oxygen flow rates (30 litres 45 litres and 60 litres per minute flow) within the three stratified groups of low median and high oxygen requirements (at recruitment to study).
Time frame: 0 to 75 minutes after start of study
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Enrollment
180