Bumex Drip Medication Error

So yesterday as I was rounding on my patients I received for my 3-11 pm shift I found that my patient's Bumex drip was completed. Since this patient was supposed to be a on a continuous Bumex drip, I called pharmacy to ask them to send another dose to me stat. The pharmacist was shocked, said that the drip should have lasted until 10 pm (it was 3:30pm). The pharmacist came up to the floor and spoke to the offgoing nurse and we discovered that the Bumex drip had accidentally been administered over 5 hours instead of 12....

The offgoing nurse reported the safety event and she notified the renal doctor who ordered the drip. He held the Bumex drip until 1am.

As I assessed the patient, this 37 year old was very lethargic/drowsy and difficult to arouse. She oriented to name, place, and event only. The patient had been on our unit about 2 weeks ago and was quite awake/alert and fully oriented. I looked into the meds she was on (Gabapentin, Ultram, Oxycodone scheduled), held the Gabapentin and Neurontin...checked her sugar (she's diabetic), sugar was 71 but I called to clarify with the MD and gave an amp of dextrose and hung D5 1/2NS. There was an order to insert a foley around 8pm since her urinary output was not where it should have been. From 8-11pm, the patient had nearly 4 liters of urinary output.

I called the renal MD and notified him, scared that her electrolytes were all out of whack so I called for labs, ABGs, and to ask to hold the bumex/diuril scheduled for later on.

So sorry for this long story, but my question is...can a bumex drip administered too quickly be the cause for her lethargy??? My charge nurse said yes. Just curious!