I was rewatching an old video on YouTube and the guy was able to walk again after 10 months of practicing yoga and losing 140 lbs. If no one on earth can exactly predict when someone will die or if they’ll be able to walk again, how and why do doctors come up with these predictions?
https://youtu.be/qX9FSZJu448
In: Mathematics
I’m an MD. The question is so broad because it’s a very different question/anwser in different clinical settings (geriatric patient dying in the ICU from sepsis vs pediatric cancer diagnosis) , and crosses different diagnoses and pathology. Usually these types of assessments are multi-factorial but a few points:
1. “Doctors told me I only had 2 days/weeks/months to live” or any permutation like that is almost never said in that format. That is usually a marketing or self-promotion trope that is used to sell you on a story or product. Doctors talk more broadly. “For stage 4 cancers the 6 month survival is usually low, honestly we could be looking that time frame or less because of x,y, or z factors”.
2. I always look for reversibility. End-organ damage is a big one for critically ill patients in particular. If tissue is dead there is no way to make it un-dead. If your kidneys fail and don’t respond to treatment and you are suddenly dialysis dependent we crossed a certain threshold. If your ejection fraction of your heart is low because that heart muscle is dead (it can be low for other reasons..excluding those) then we can’t expect that function to recover only managed.
3. Always consider the broader context of the patient’s health. If someone’s grandparent has dementia and has lost function every year for the last 5 years and now they have a diagnosis with limited reversibility… It’s silly to expect them to every have a quality of life better than what their established baseline has been if there is a major insult requiring ICU care as an example.
4. For patient in the hospital that are really entering the phase of actively dying (signs of death, nothing medicine can reverse) we look at trend in vital signs, end-organ damage, failure to respond to treatment. Later signs include agonal breathing, skin mottling. By then we’ve usually already spoken to the family about changing or goals from treating the pathology to treating any pain and air-hunger and making the patient comfortable (i.e. we are shifting our goal in particular because there is no demonstrable reversibility). Prior to that we always give a warning shot before giving bad news and then say something like “[the patient] will not survive this hospitalization, it’s hard for doctors to predict but there isn’t much time”. For certain situation it needs to be direct. It’s always nested in a long sweeping summary of what has happened, why there was no improvement, and how we can move forward.
5. So a summary to that is: it’s a combination of blood work, imaging, vital signs , physical exam, reversibility of problem + the context about the patient’s health + what the published data shows about that particular disease stage. (Sorry not a great ELI5)
I am a surgeon.
The best answer I can give you is similar to the others, but i will try to expand on it
For conditions that are common, for example cancer, there are thousands and thousands of data points for patients. Age, stage and grade of tumour, comorbidities, spread to lymph nodes metastatic disease, etc. These factors often interact in complex ways, but some very smart people have created models and risk calculators to help with predictions. For cancer, most predictions are made based on median survival. This refers to the amount of time passing where half the patients are still expected to be alive.
As an example (skip to the end if you’re not interested) a risk calculator exists for patients with metastatic kidney cancer. It has 5 risk factors. If you have none of them, median survival in 20 months. One or two, 10 months, and 3 or more, 4 months. This information can help patients make decisions about which treatments they are interested in and how aggressively they want to fight their disease. But as I mentioned above, this is median survival, not a crystal ball that applies perfectly to you as a person.
Physicians are often poor at having these conversations for a number of reasons that I would be happy to get into in a separate response if anyone is interested. I can also expand if you would like. But hopefully that serves as an introductory answer to your question.
I work in Opthalmology – This is why we always are guarded about questions like “When will I get my vision back?” One of my colleagues, no matter how severe or minor, will usually say something to the effect “let’s take it one visit at a time. Be patient.”
He has some of the best bedside manner in a particularly stressful role (people care about their eyes as you may imagine.)
However, we can give estimates for a prognosis based off of YEARS of study, experience, and empirical data.
As a funny side note, one of my Retina colleagues, when he has a good report with a patient who is blind for whatever reason (old retinal detachment, central retinal artery occlusion, etc.) will have patients ask if there is anything “new” in the field to give them their vision back and he will say, “Well there’s apparently this Jewish Rabbi from Nazareth apparently…” and most of our elderly patients get a kick out of that.
I’ve always thought the doctors who said “you’ll never walk again” are a lot like the people who said “you’ll never amount to anything” in someone’s childhood: mostly fictional. Is that what they said, or what you heard?
Just a heads up, this guy in the picture had a broken back and wound up fully rehabilitating using a certain type of Yoga. It was a former pro wrestler who developed the yoga style, and I remember seeing this on Shark Tank! This guy went from a fully broken back to being able to do full splits. Really inspirational
Doctor here:
You can’t really do this, except on a handful of diagnosis, there are big studies that compare outcomes based on factors that the patients have, age, weight, etc, and in cancer we use the type of cancer as well as the stage of it (how bad has it gone).
These studies tell you roughly how much people who have certain characteristics live with a diagnosis, I personally don’t like to do predictions but I’ve met oncologist who actually do them very accurately.
There is a great debate on whether predicting mortality is ethical or not.
From my experience as a physician, I’ve found that predictions regarding longevity with a disease or return of function after a disability are rarely correct. We can say what other people similar to the person have experienced but it is an imperfect prediction at best. I don’t speculate on this kind of thing unless the patient is insistent that I come up with a number or a “yes or no” answer. When I see posts about “The dOCtER said I’ll NeVeR WaLk AgAIn“ I often shake my head because I know that the doctor was probably forced to make a prediction because that’s the misconception perpetuated by the dramas on TV.
ER doctor here. I can’t make great predictions on when someone will walk again, or how long they/ll live with a new diagnosis of cancer. But, I can pretty accurately predict how long you have left (minutes, hours, days) with one very important test called the Arterial Blood Gas. Its a blood test we obtain from the arterial blood and it gives us a data set of a few values, including blood pH, partial pressure of O2, partial pressure of CO2, and lactate level, among as few other things. I think my Respiratory Therapist friends can also attest, after you do this job for awhile and it becomes intuitive, these collection of numbers paint an overall picture on whether someone’s respiratory/metabolic compensatory processes are doing well, compensating, or failing.
The numbers mean nothing if you don’t know how to calculate and interpret them. In fact, most students/residents are able to correctly calculate them, but have trouble extrapolating that to a prognosis. At this point, I can quickly glance at the numbers and have a good idea if the patient in front of me is about to die if I don’t do something quick, will die no matter what I do, will make it through the night but will die in the morning, or can be stabilized, but will likely not maintain survivability over the next few weeks.
It seems like mumbo jumbo, but over time I am surprised by how accurate my guesses are. For example, one time an old man with shortness of breath had pristine vitals. Normal blood pressure, heart rate, etc. Looked well. The Arterial Blood Gas suggested he was likely to decline. In this instance, the he and the family opted for Comfort Care (no interventions as his cancer was very progressed). I told the family that, without intervention, he was likely to rapidly decline within the hour, and he would likely pass in about 2-3 hours. Like clockwork it happened exactly like that.
I think the “you have X weeks to live” is a product of hollywood more than it is reality. No doctor I’ve worked with makes predictions like that. They might say something like “the data shows that most people take X weeks to recover” or talk about 5 year survival rates with the patient, but I’ve never heard them say ” you have X months to live” because, as you note, they just don’t know. They’ve all had patients who improve for a while, only to suddenly deteriorate and pass. On the flip side, they’ve all had patients who beat the odds for years, sometimes even decades.
The only time I’ve seen them make a specific prediction, is when filling out Death with Dignity paperwork, which requires the patient to have less than 6 months(in my state at least).This is usually based on averages I assume, but honestly it could just be an (informed) guess.
A mechanic can give you an estimate on how long to repair a car, a baker on how long it takes to make a cake, and a doctor on making a recovery.
Through education and experience, professionals have a generally good idea of how long certain stuff takes to complete. Sometimes things happen outside of our expectations and knowledge, which leads to unexpected outcomes, like a patient who recovers quickly or a cake that fails to rise. Generally speaking, as you get better at your job, the number of inaccuracies will decrease over time.
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