Never suction a baby that's already bradying down unless you have absolutely NO choice. Desatting baby, yes suction. Bradying baby, no. You'll brady it further and then you have a HR in the 40's. My rule of thumb... Learned the hard way.
Never remove an ETT, assuming a baby has self extubated to give PPV via bag and mask without careful consideration. Especially micropreemie. Get someone else's opinion. Sometimes you can't get another tube in and then you'll likely have a code with no airway. Maybe lethal. I've seen it happen, baby died and may not have been extubated in the first place.