Pressure change with longer hose- revisited

HeatherN · Post by **HeatherN** » Thu Jul 26, 2007 5:49 pm

I know we have discussed this before but.... recently Hannah went from a six foot hose to a ten foot hose. She flops around her bed so much she was pulling the hose of her mask. Anyway when we switched I asked both the DME(respritory therapist) and the sleep DR if she would need to change her pressure and they both said no. So after we switched I started noticing a weird thing when she was sleeping. She would almost struggle to breath with her CPAP on. It is quite strange, it's almost like she is having retractions, and her whole body moves when she takes a breath.(I mean a lot-not normal looking) It scared me and I showed my hubby and he agreed that something is not right. So I video taped her sleeping and took it to her Sleep DR. He watched it and then also had a respritory therapist watch it too.The RT thought it was because the hose was facing down her chin rather than from over her head. She tried to say it was possibly was because her mask was not exactly straight in her face. So I went home with this in mind and was real careful about hose position(put it over her head board) and that her mask was prefectly straight. I did all these things and she is still having issues. So the DR called in a scrip and the DME upped her pressure today. She has yet to sleep with the new pressure setting but it really makes me wonder if the new hose has anything to do with it.Has anyone had a similar experience?

oceanpearl · Post by **oceanpearl** » Thu Jul 26, 2007 6:38 pm

1 PSI is 1 PSI, no matter the istance travelled. Somethinse must be goig on.

Guest · Post by **Guest** » Thu Jul 26, 2007 7:28 pm

oceanpearl wrote:1 PSI is 1 PSI, no matter the istance travelled. Somethinse must be goig on.

Not quite correct, first it is centimeters in H2O not PSI which is Pounds Square Inch, huge difference in pressure.

Pressure is LOST the longer the hose used to static resistance of the hose, in the case of a spiral cpap hose it may even be higher due to the ribs on the inside (vs a smooth surface).

The only way to know for sure is using a H2O manometer and measure the pressure at the end of the hose. Not only may it require the pressure be increased 1cm higher, if the machine happens to be an autopap designed to work with specific length hose like a 5-6ft or 2m hose and you nearly double that, the machine won't be able to sense the patients SDB and respond appropriately.

dsm · Post by **dsm** » Thu Jul 26, 2007 7:44 pm

Hi,

Did a lot of research here that showed clearly that longer hoses lose pressure & the faster the air travels (is breathed) the greater the loss.

When no breathing is taking place ( and if the mask leak holes get blocked ) the pressure is the same from one end of the hose to the other - when breathing in and the air starts flowing, the losses start & the distance increases the losses.

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DSM

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Guest · Post by **Guest** » Thu Jul 26, 2007 9:21 pm

Heather, what machine is your daughter using?

Snoredog is correct, if she is using anything other than straight CPAP, and I mean ANYTHING (C-Flex, Auto, BiPAP), the hose lenght will affect how the machine operates.

dsm · Post by **dsm** » Thu Jul 26, 2007 9:39 pm

[quote="Anonymous"]Heather, what machine is your daughter using?

Snoredog is correct, if she is using anything other than straight CPAP, and I mean ANYTHING (C-Flex, Auto, BiPAP), the hose lenght will affect how the machine operates.

Guest · Post by **Guest** » Thu Jul 26, 2007 9:50 pm

Yup, your right DSM.

I stand corrected, I completely forgot about that.

We often get to talking so much about Respironics and Resmed machines that I forget some people use other machines. And imagine, even I have a 420E sitting in the closet!! hehe

dsm · Post by **dsm** » Thu Jul 26, 2007 10:45 pm

[quote="Anonymous"]Yup, your right DSM.

I stand corrected, I completely forgot about that.

We often get to talking so much about Respironics and Resmed machines that I forget some people use other machines. And imagine, even I have a 420E sitting in the closet!! hehe

HeatherN · Post by **HeatherN** » Fri Jul 27, 2007 4:35 am

Hannah has a REMstar PRO m series with CFLEX.

KAZ · Post by **KAZ** » Fri Jul 27, 2007 5:03 am

After pulling the hose loose several times(pressure 20) I went to a 10' hose which has solved the loose hose problem. I have not noticed any change in my treatment.

Pressure change with longer hose- revisited

Pressure change with longer hose- revisited

Hose lengrh