Some doctors go crazy and admit, but most manage lower counts on an outpatient basis. The times you might experience an admit is upon initial diagnosis, generally when counts are below 10-20k, which might be because the doctor does not know how you'll respond to the low counts. He would be concerned with a person bleeding, so might err on the side of caution and admit as he initiates treatment. If you've worked with this doctor, he'll probably continue to treat outpatient, unless you counts drop to a new low, such as below 5-10k, although some doctors won't admit unless he seeing evidence of soft tissue bleeds. This would include mouth blood blister, or very heavy, non-stop menstrual or vaginal bleeding. If a CBC shows a low RBC or hemaglobin, he may suspect internal bleeding and if you're counts are low, he might admit. It really depends on the doctor, what his risk tolerance is and if his risk tolerance does not compare with yours and you're uncomfortable not being admitted, or don't want to be admitted, this is something you should discuss with your doctor. Get a good feeling on what his risk tolerance is and work out what works best for you and for him. There really is no standard protocol for admitting an ITP patient.
I prefer to be admitted if I show bleeding and my counts are below 10k, or if I'm below 5k and not showing any symptoms, except petechiea. I just think 5k or lower is way to low. But, I have decided that admitting isn't necessary at 5k or below, so I won't stand by that with strong convictions. I think it all depends on what else is going on, how I'm feeling, dealing with the stress of a drop in counts, etc. It's not black and white and I prefer a physician who will work with me in making the decision.
When you're a long standing ITP patient, when you switch doctors, you might experience a doctor who treats you as if you were a new patient, in that he'll admit at a higher platelet count then you might prefer. That's why it's important to maintain a relationship with a hematologist, so he understands you and your particular ITP progression and response to treatments. Make sure you provide any new hematologist with a complete write up of your history, which includes all treatments and response to treatments and how you've managed low counts. If he sees that you are an active, involved patient, he'll be more inclined to trust your judgement.
If you've developed a relationship with a hematologist and he won't trust your judgement, you feel is too aggressive on treatments, hospitalizes when you feel it's reasonably safe and just doesn't seem to want to work with you, it's probably time for a new doctor. Unless he can convince you why he's recommending a treatment, takes the time to explain, it's probably time to find another one. You want someone who helps you manage ITP, because you'll probably be managing it for the rest of your life. You don't want it to rule how you live, causing fear and anxiety. It will be hard enough to manage ITP and the ups and downs of platelet counts, so undue stress of a doctor who is anxious or a bully will just make matters worse.
Regarding nurses -- if you're seeing an oncologist, who treats cancer patients, sometimes nurses are responding to how a cancer patient would be with a count below 50k. Often they will bleed, because they not producing the large platelets an ITP patient produces. The nurse might not completely understand ITP, so when she sees a count of 16k, she thinks internal bleeding. In ITP, the risk of a bleed is higher than if you had normal counts, but it's really still a very low risk, unless you happen to be a patient who does bleed. Therefor weigh the response of an oncology nurse carefully, until she fully understands your ITP diagnosis. I've seen nurses really over blow ITP at counts below 50k, but not below 20k.
Make sure you completely understand your ITP and ITP in general, treatment protocols and work to manage your ITP, as opposed to dumping it completely in the lap of those who treat you. You'll appreciate hanging onto some of the control and I suspect your doctor will appreciate an involved patient.
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