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→What is the oxygen concentration in the diluted CPAP circuit?
=What is the oxygen concentration in the diluted CPAP circuit?=
The equation to calculate concentration from flow is:<br(oxygen flow rate (litres) at 100% O2 ) + (air volume (litres) at 21% O2)) / Total air volume = oxygen concentration %Percent in circuit <br>therefore, at 1 litres/minute oxygen addition at 100% and assuming a total CPAP flow of 30 L/min:
(1-L/min x 100) + (30-L/min x 21) = 730/31-L/min = 23.55% Oxygen.
at 1 3 litre/minute oxygenat 100%
(3-L/min x 100) + (30-L/min x 21) = 930/33 L/min = 28.18% oxygen.
Any variable can be changed based on available data. If the flow rate is 40 L/min from the CPAP, the oxygen concentrations will be higherlower. If leaks are present or pressure results in a higher average vent-rate, the oxygen concentrations will be lower. For oxygen concentrators, it is important to use the oxygen percent output by the concentrator. While bottle oxygen is pure at 100% oxygen, a concentrator may put provide a concentration of 75% to 80%. The proper value can be determined from the machine specifications and input to the formula.
=xPAP Flow Rates vs Pressure=
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