I would have carried out the order. How long of a time frame was it from the time the order was written to the time it was canceled? An ABG can tell you many things. This patient had multiple problems going on, all of which can affect ABGs (high glucose level, CHF etc). The result may or may not have changed the admit destination for this patient. It may have alerted the doctor to keep an eye on another potential problem emerging during the patients hospitalization. It would also be a good baseline to reference should the patients condition change.
I am sorry, but I do not buy that by not carrying out the order, this is facilitating the other orders to be started. An ABG takes. . .10 minutes?? Do you have RT's in the ED? Do you as a nurse draw the ABG? RT's draw the blood gasses in my department and have a blood gas analyzer right there in the department. Even so, when drawing a co-ox off a swan (which the RNs do), the results come back from lab in about 10 minutes.
Should this order have not been canceled, I predict the patient would have gone to the floor, the receiving nurse would now have to address this issue, arrange for it to happen, amidst the whole addmission process that we all know takes a long time (paperwork, paperwork), still keep up on the other patients she/he has as well as verify all the other orders that need to be done.
As a manager, I would expect more out of you with your 28 years of experience, however, I would not terminate you.
Just my .02 cents.