We actually had an OB patient that did this kind of crud. Severe cardiomyopathy at age 25 due to excessive use of crack. 10% cardiac output on a good day. Could've dropped dead walking to the bathroom. Used to come in to the hosp. in SVT's, freaking out, fresh off a crack binge. Would stay a few hours, come off the crack, and sign out AMA. We finally got her involuntarily committed at 28 weeks.
ANYWAY, she had this nasty little habit of going down for 'smoke breaks' and coming back high. Her MOTHER was her dealer, so it was quite easy for her to pull off. Once the docs and nurses figured out what was going on, it was mandated she had to have nursing 'supervision' to go for a smoke break. Couldn't be a CNA either, due to her severe cardiac probs....the 'supervisor' HAD to be a nurse. Needless to say, she stayed sober until we delivered her.
If involuntary committal is out of the question, try getting the docs to sign an order on her chart that a nurse has to go with her on smoke breaks like we did. It was a pain in the a**, but it worked well, and was better than having to deal with a patient high on crack....plus, when you have to have a 'babysitter' to go with you for every smoke break, you want to smoke less and less and less...

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