Why shouldn't the person be allowed to make their own choice after being properly informed of their options and having received their doctor's suggestion?
If the broken toe was inside a concrete cast that no one could see into, and there was no such thing as an X-ray machine, CT scan, MRI, or any other machine that could be used to verify the toe being the part that's broken.
If the doctor didn't listen to, or at all believe at least half the the stuff the patient actually said, and didn't need to.
If others had leg amputation performed and the leg grew back and on top of it we had evidence that leg amputation caused long-term damage when performed for other reasons. (Ketamine has long been used as an anesthetic precisely because the data we have suggests no long term damage from that dosage.)
If the patient had suicidal ideation and intent, because something hurt so much and we had no way of doing anything other than leg amputation, then why shouldn't we?
Until humanity manages to develop and deploy brain scanners that can actually see how much physical and emotional pain a person is actually in, then the leg amputation analogy is lazy and unhelpful because we simply don't have the same tools to address mental health because it's largely invisible.
Most doctors are still humans who negatively judge patients who drink heavily, who frequently miss appointments, who can't manage to get lab work done, who self-medicate with street drugs; those patients are judged as degenerates, not deserving of their help because they can't manage to take a pill, that doesn't seem to work for 6-8 weeks.
I mean, it's great that a hospital's ethic's board has reviewed the situation and determined that the best course of action is for people to suffer because they don't want the liability of, in this analogy, leg amputation, but in the meanwhile, people are being discarded by the mental health profession.
But what treatment are you thinking of here? Ketamine? Maybe after more research, trials and long term tracking of patient outcomes it can become a front line treatment. For now there's a reason it's a treatment of last resort. It's use in this way is not as well understood as traditional drugs. Use as an anaesthetic is a one-off. As with most substances, chronic use carries more complications. There's potential for cardiovascular issues. Also cognitive issues like impairments in creating new memories, accessing old memories, verbal memory, forgetting words, names... It makes sense to attempt treatments with a lower risk profile first, not for legal liability but patient well being. In the meantime there already is an immediate treatment available for those at risk of self harm: short and medium term hospitalization, which allows for more rapid trials of different medications at higher doses because the patient is under regular monitoring. Yes it still sucks, it's a crappy experience, but it is effective in getting most people stable enough to wait for longer term treatments to reach peak effectiveness.
> It's use in this way is not as well understood as traditional drugs
Traditional drugs are often a crapshoot anyway, and there's been plenty of harm from them. In the end, it should be the patient's choice in what path to take.
Yep, traditional drugs have their pitfalls too, but have had the advantage of rigorous trials that something like ketamine has not yet undergone. I'm glad it's an option, but there's really not a strong enough body of research for it to make it a first-line option. Yet. I hope that changes.
And, in the end, it is the patient's choice, within a certain circumscribed set of options. A good doctor works with the patient's needs. But it would be a very poor doctor that jumped to riskier options and less proven options first. The level of patient choice you're suggesting implies a level of informed patient that is frequently not the case. I rigorously research every single treatment option, discuss each one with my doctor, and we arrive at a course of treatment. But my doctor has indicated that I am, unfortunately, in the small minority in this respect. Your level of patient choice would invite all sorts of bad prescriptions to patients ill informed and, often, self diagnosed incorrectly-- a frequent issue leading patients to skew their conversations with doctors towards that incorrect diagnosis. In theory, in a perfect world, what you propose is fine. But we don't live in that place.