I am a float nurse in my hospital. We recently opened a PICU. It's 4 PICU beds, 2 swing beds that can swing to PICU or IMCU or back to general peds.
The last time I floated there they had 3 patients, 2 PICU nurses and me. - no unit clerk. They had a scheduled MRI for a vent patient so they knew one nurse had to go. Sure enough, the other 2 got busy, we were hanging blood, there was no unit clerk, the phones were ringing off the hook, etc. The 2 of us together were fine, but if that nurse was alone she'd be toast.
Our pediatric floor will help out if they aren't too busy. They usually have 3 or 4 on days and pms. They have a lot of chemo patients.
We also have SWAT
nurses. They are the best since sliced bread. They come rescue us in so many ways. They are not assigned to a floor like float team. Supervisor assigns them, or they make rounds to see who's busy. They start hard IV's, they insert PICC lines, they help with admissions. They often pick up the patient from ER, get the history, get your vitals, start your IV's, give any admission meds, then they just give you report. It's wonderful. They respond to codes not as part of the code team but to see if the nurse has other stuff to take care of such as meds for other patients, start packing up the patient for unit transfers, make phone calls to family - whatever you need. They will irrigate a clotted catheter - whatever.
We only have 1 or 2 SWAT nurses on per shift. So she has to prioritize when she gets more than 1 call. They work 10Hr shifts so they overlap our 8Hr shifts.