Sorry, I can't help you with that, never done it or read anything on it. I hope you made a mistake in your wording.....
"I'm planning to insert a catheter to her stomache and fill her up with about 150ml of soapy water."
Not sure on the affects of soapy water being used as an enema, but IMO it's NOT a good idea to put "soapy water" in her stomache. Unless you have somebody in the know telling you what soap and what concentration to use, I can't see ingesting soap as being good for any animal.
Maybe it's time to see a vet?
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Thanks,
Dave Colling

www.rainbows-r-us-reptiles.com
0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)
LOL, to many snakes to list, last count (05/26/2009):
36.51 BRB
29.42 BCI
And those are only the breeders 
lots.lots.lots feeder mice and rats 

