In my opinion, your style of hospital would determine what to focus on. Are you doing all 1:1 treatments with portable machines? If so, you should invest a lot of time into machines troubleshooting and how the machine operates. Understand What each part of the machine does and how you might fix it. Especially if you're going to be on call and get called in the middle of the night with no available resources. The worst feeling is having a STAT treatment to do, with ICU nurses waiting on you, and then you have machine problems. Make sure you know what the alarms mean and what might cause them. You're going to have to be an independent problem solver. May not have anyone to ask, just might have to figure out technical problems on your own. Ask your preceptor Togo through some hypothetical problems that may occur. Of course when you're with your preceptor, everything will go smoothly because they know exactly what they're doing. But what about when you're on your own? Can you fix these alarms?
Of course patient assessment is very important. If you have been a nurse for a while, you will be good with your assessments. Watching the blood pressure very carefully and being mindful of trending will help. Look at the previous treatment sheets and see what is normal for that particular patient. They might have a BP of 156/85 and then 15 minutes later they suddenly bottom out at 80/44 and pass out on you! Not typically, but it is important to notice trending with the patient.
I had been doing dialysis in the clinic one year before I move to Inpatient, and I can tell you that I was terrified to do my first treatment in the middle of the night with no back up. I was so afraid the machine would fail or I would have water pressure issues or who knows. I highly recommend learning that machine!! Of course if you have a hospital based inpatient clinic where you will have help, that's totally different.
One other pointer- always have CONSENT! And make sure Patient has a working access before you fly in there at 2am. Secure your hoses so you don't flood the room.. What an embarrassment that had been! Lastly, take your time and DO NOT skip any steps with set up. Very important to slow down.