Sleepyhead question about leak rate

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menlodoc
Posts: 9
Joined: Sun Nov 13, 2016 3:42 pm

Sleepyhead question about leak rate

Post by menlodoc » Mon Jan 09, 2017 4:38 pm

When sleepy head gives you "% of time above Leak Rate threshold", what is the significance of this number? For example if the number is 17.28%, does this mean the cpap was unable to function properly 17.28% of the time during the night due to leaking? Or does the machine function normally in terms of measuring AHI and providing appropriate pressure during this time. In addition to this number (17.28%) for percent of time above Leak Rate threshold, sleepyhead also shows Large Leak = 8.58% for the same night.

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OkyDoky
Posts: 2869
Joined: Mon Aug 25, 2014 5:18 pm

Re: Sleepyhead question about leak rate

Post by OkyDoky » Mon Jan 09, 2017 5:27 pm

menlodoc wrote:When sleepy head gives you "% of time above Leak Rate threshold", what is the significance of this number? For example if the number is 17.28%, does this mean the cpap was unable to function properly 17.28% of the time during the night due to leaking? Or does the machine function normally in terms of measuring AHI and providing appropriate pressure during this time. In addition to this number (17.28%) for percent of time above Leak Rate threshold, sleepyhead also shows Large Leak = 8.58% for the same night.
Well, it may mean you just need to look at what the Flag leak threshold is set at in Sleepyhead. I believe it is set around 24L/min because ResMed states their machines will compensate up to 24L/min. ResMed only measures unintentional leaks in their machines.

But you have a Respironics machine and they compute total leaks, which is both the intentional (venting) leaks and unintentional leaks. To determine the venting rate for your mask you can look at the mask manual or online. It will show a graph where the venting leak rate increases with the pressure increases. Usually this is around 40 to 60 L/min so you can add that onto your unintentional leaks. You can reset your leak flags by going to File-Preferences-CPAP then on the right you will see Flag Leaks over Threshold that you can reset. I have mine around 70 usually for my Respironics machine.

Always look at your leak graph on the right to see how much and how long you had leaks.
ResMed Aircurve 10 VAUTO EPAP 11 IPAP 15 / P10 pillows mask / Sleepyhead Software / Back up & travel machine Respironics 760