Use of Droperidol

I'm a nurse in the Outpatient Endoscopy Unit of a large teaching hospital. Our physicians continue to use droperidol when versed and fentanyl do not provide adequate sedation.
As nurses, we became more and more concerned after the FDA issued its black box warning for the drug.
We are now required to have a 12 lead EKG prior to the procedure and continuous cardiac monitoring of the patient for 2 hours post administration. We're still concerned about re-sedation effects.
Anybody have any suggestions or literature that can help settle the debate within our unit.
Appreciated
Anna Maria