How much leak on the masks is acceptable?Why am i having so many variations in the pt.'s tidal volume and minute volume below my alarm settings? No manner how low i set them they still alarm.Thanks for input.
Your leak needs to average less than 20 lpm or so and the I-Trigger needs to be set above what ever average leak you are seeing ... A good place to start is 15 lpm on I-Trigger also a faster rise time like .2 or .3 , an E-Cycle at 35-45 also helps the patient cycle into exhalation faster.
As for the Vt and VE the patient is going to very that on there own quite a bit.
Also a newer style mask like the Respironics Performa-Trak face mask, will help reduce the amount of leak your having. Tri-amin has them in available and they have only been out now a few months.
Best of luck, if you need further help call 800-345-6443 RI has the best clinical support !
John Heaston RCP
Sr. Clinical Specialist
To expand further, and answer your question directly. Literature states 7-25lpm leak. Second if you are using a full face from Respironics, be sure to rotate the mask from below the lip first then sit the top of the mask just below the bridge. Bi-pap units only estimate volume bases on flow that is delivered and flow can vary from leaks tremendously. Bi-pap delivery is pressure support and pressure support transitions into ehalation first by reaching flow termination criteria. If your leak is not compensated for with the unit you are using, (like a Vision)then it will continue to deliver flow, which now you can certainly understand why your readings can go North and South. Bottom Line: get your leaks under control.