This happened to a nurse friend of mine when I was working in ICU. The patient's PTT was high so the Heparin was put on hold and the patient was also being discharged to the floor so the ICU nurse just pulls it from the pump and clasps the IV tubing and takes the pt down. Well, sometime later when the floor nurse checks the pt the Heparin bag is empty(it was full) and it had went in wide open. Luckily, the pt was okay, there was a lot of argument about whose fault it was but the ICU nurse was the one who got wrote up.