I agree with Archus. Although, I have done colonics with Sea Salt in water at home and I find them pretty effective. Especially if the bowels did not function properly to start with, as in after surgeries, missing appendix etc. so there is stuff stuck in there to rot and produce gas and intoxication. However if you are inexperienced with these, you probably better not try them for a first time during a fast.
Regarding your previous hospital stay, you did not consume food through the mouth, but almost certainly you had nutrition in the IV; I don't think you were metabolically fasting then - your body did not use its reserves to fill up energy needs, therefor I believe you were not fasting then.
Take care to monitor your GIT and if unbearable, maybe restarting the fast after preparing better would be a better option. I don't want you to land with a bowel perforation.