Fluid Boluses

I'm a new grad RN and on the last couple weeks of orientation. One of my pt's had low urine output so I got an order for a fluid bolus. The doc wanted to give a 250mL bolus instead of the usual 500mL due to questionable CHF. I've always had questions about how fast to give a fluid bolus. When I was a nursing student, I would ask my preceptors and never got a straight answer. They would say "it depends on the pt," so I've seen one nurse give a bolus at 100mL/hr and another nurse give it at 250mL/hr for a middle-aged pt with good veins. I've never seen anything faster than that. My pt had questionable CHF, +2 pitting edema, and the last bp reading was 145/85, so I decided to run it at 100mL/hr until I could ask my preceptor what rate she recommended. The night got busy and I never had a chance to ask so once bedside report came, my preceptor called me out and pretty much called me an idiot in front of the pt, the oncoming nurse, and nursing student for running the bolus so slow. I felt so dumb and embarrassed. Can anyone clarify how fast to run the bolus? Thanks.

Not at all what you're asking about but I'd have been questioning an order for a bolus over diuresis. It sounds like the patient has plenty of fluids on board.