size does matter ~ sizing p-valve caths

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Halcyon's p-valve ships with one size 28mm (medium) external cath. This may or may not be the correct size for you.

You can manage to get a smaller sized cath on, but it isn't necessarily a wise or healthy course of action. Not only that, a cath too small is more likely to come off at an inopportune moment. If anything it would be better to err on the side of slightly larger cath.

Here is a simple solution to the sizing issue:

Using a compass set to 25mm 29mm 31mm 36mm 41mm (Rochester sizes) draw circles on card stock (you can do this with a couple of 3x5 index cards.)

Cut the card stock with scissors so that you cut the circles you have drawn in half and then cut out the interior of the resultant semi-circles to form the *sizing gauges*.

Now size yourself. If you are somewhere between sizes order the larger size.

Tip: best prices are here.



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what is the 25mm 29mm 31mm 36mm 41mm you reference .... circumference is all i can thnk of.

thanks
 
It's either radius or diameter -- whichever the readings on the compass are.
 
It's either radius or diameter -- whichever the readings on the compass are.

41mm radius???? I know you're a Dr and probably seen more than I have but that seems a little outrageous to me.
 
Are these sizes artificially inflated so that our egos all get a boost when we order? For once in my life I can say I need an XL!
 
https://www.shearwater.com/products/perdix-ai/

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