We have one 1st call RN for PACU weekdays. The second call goes home around 1900. We cannot call her back in.
On weekends, we have a 1st call and a 2nd call - however, the 2nd call cannot take 1st call. So, they are of no help if 1st call is sick, or was in an MVA on the way to the hospital. They are only used to assist 1st call.
It is also frowned upon to actually call them in. Lots of gossip if you actually do, and then the 2nd call argues about taking 2nd call when your 1st call. It's a really ridicules and dangerous situation.
We once had a nurse who was on first call, had to stay with a patient in pacu overnight because the floors had no rooms. She worked 23 hours straight. She called our boss at home and was told she could try calling others in, she called the supervisor and was told "You can't leave and abandon your patient, deal with it". I came in a 0700 and took over for her, I would have come in earlier if notified.
It's a sucky place to work. We work every 6th weekend on call. My last weekend I worked 30 hours. 20 straight hours without sleep. No one cares, it's expected you "suck it up". It's not safe.