I understand why it is wrong for doctors to sleep with their patients. Position of trust, responsibility, vulnerability, etc. But what about other hospital / clinic staff? Are there any ethical or professional prohibitions preventing say, orderlies, technicians, maintenence staff, among others, from having a relationship with a patient?
Does your wife know that you have a crush on your x-ray tech? 
Yes. There are ethical restrictions placed on hospital personnel at hiring. Of course, after a patient is discharged, they are no longer a patient, now are they?
Seriously, I’ve know nurses who have married patients. I think it’s more than a little strange, but, that’s just me.
Are you talking about people who began a sexual relationship while one was a hospital employee and the other was a patient? How would that work, exactly? Are they doing it in the hospital room?
Actually boinking while one person is still in the hospital is sort of weird. But once they leave? Nearly everyone goes to the hospital for something at some point.
I would imagine psychiatrists boinking even ex-patients would be something of a no-no.
Hence my confusion. After they leave they are no longer a patient. Why would ethical considerations apply then?
This is the scenario I had envisioned. And before you object, let me point out that it happened to a friend of mine.
No objection. To me this is clearly unethical.
What? You mean porn films show unethical behavior? I’m shocked. Shocked!
Now we’re getting somewhere. Why is this unethical? What duty does, say, the X-ray tech have, that would make it wrong for her to bonk me if she were so inclined?
For starters, I am assuming that your treatment protocol excludes sex with anyone. It would certainly be against medical advice.
Here is the Radiologist Code of Ethics
http://www.asrt.org/content/RTs/CodeofEthics/Code_Of_Ethics.aspx
Screwing someone while at work is unprofessional. She is getting paid to do a job. Banging the patients is not in the jub description.
You can find similar codes of ethics for other medical professions using Google.
That is why people get lunch hours. Nothing like a nooner at the office.
I expect that if you were to survey 100 HR people and ask them why people get lunch hours, less than 1 would give this response.
[Jim Carrey]So you mean there’s a chance![/Jim Carrey]
And you would, unfortunately, be incorrect. We (and I extend this out to all folks in the mental health field who are subject to the rules of the American Counseling Association/American Psychiatric Association/Clinical Social Workers) have a two-year waiting period during which we’re not allowed to see clients socially (platonically or sexually), but after that all bets are off. I know of several colleagues who routinely cull their dating pool from their client list, including at least four marriages.
I personally stand by my iron-clad rule of “You don’t fuck crazy.” 
Actually, according to American Psychiatric Association Ethics, sexual activity between current or *former * patients is unethical. That’s what I was taught during training.
Hrm… is that new? Because I can tick off at least four people who are violating that right now, and that’s just off the top of my head…
Sure they are. You quoted it yourself:
So when they are bonking them, they are just simply responding to a patient’s needs.
Granted, those needs are not necessarily related to their actual medical problem, but they ARE responding to their needs.
What?
It’s the crazy ones that have all the good pills.