What medical problems would doctors in a far future setting, plausibly have trouble dealing with?

Question

This is based on another thread in regards to how you can avoid having sci fi technology be a deus ex machina.

So when it comes to writing inorganic technology, IE spaceships and laser guns, the laws of physics seem to give us the shape of what is vaguely feasible and isn't in regards to what you can build.

With most hard sci fi being able to extrapolate and selectively tweak those limits to get what they want.

For example if I wanted a laser gun. An analysis can easily look at limitations like waste heat, energy density of the battery, and other features.

Medicine sets a boundary on what a character can recover from in the event of injury or disease. Yet I find it difficult to predict what is and isn't a difficult problem to solve in the field of medicine. Most hard sci-fi I've read goes with making medicine easy. IE you can cure old age with just some nanotech pills. They can clone limbs and organs like printer paper.

Other times the topic of medicine is grounded mainly in the familiar. In Star Wars it never sat right with me that a Galaxy had the technology to mass produce clone soldiers. Yet a Senator's wife in a wealthy and developed planet had problems with her fertility.

Is there a non-arbitrary way therefore to figure out what kind of diseases would trouble people in a sci-fi setting?

Answer 1

The Limiting Factor

Using medicine to set the boundaries is backwards. Begin with the body itself. The human body, the physical part of it anyway, is the product of a long evolutionary process. It has plenty of strengths, such as stamina, but also plenty of weaknesses, such as relatively weak bones.

The body itself sets the boundaries for even the most advance medicine. It can only take so much punishment and suffer for so long before it simply dies. These are the kinds of limiting factors you'll want to look at. Things like oxygen deprivation, carbon dioxide build up; maximal G-forces; maximal blunt force absorption; stresses that skin, connective tissues and bones can handle.

Your advanced medical technology might be able to grow a heart in a bottle, but that doesn't do much good for a person who has just been given a whole new set of orifices with a laser rifle or a kinetic weapon of some kind. Similarly, and this is something that is often glossed over in SF, if you get that bottle grown heart into the patient before she dies, you're still invading her body with surgical intervention of some kind. She will need to recover. Her organ systems have all been compromised by the injuries she has sustained, she's lost a lot of fluid, she's in shock. If she's suffering from something like Crush Syndrome, that heart's not going to do much good, because her body is releasing all kinds of toxins that can lead to serious organ injury, failure and even death.

Bugs. Not every disease is curable. Microbes and viruses continue to evolve. Particularly to avoid extinction from antibiotics and antivirals. Some creatures, like the common cold, we just have no ability to kill them off. There are plenty of other wee creatures out there too. You could posit that, due to space travel and contact with other worlds, a variety of viroids, prions, or other invented submicroorganisms have been on the rise. These might be debilitating or deadly diseases elsewhere in the galaxy, but in humans, just cause a minor but incurable disease state.

Answer 2

I'm going to answer this tangentially, as a semi-frame challenge, and hope this gives the inspiration.

I would start with what technologies/capabilities you want your Sci-Fi Medicine to have - and that will largely dictate what will still be an issue and what won't.

Also to add - just because something is capable of being done, doesn't always mean it's reasonable to do on a mass scale.

So let's start:

Artificially growing organic replacement body parts

This is a big one for all your bog standard trauma issues - if you have the ability to grow a new leg or new organ, many of of your injuries can be mitigated by simply replacing the damaged part.

Gene replacing/sequencing/therapy

If your world has the ability to reliably edit Genes, then all your genetic ailments could be mitigated - whether that's Down syndrome or simply male-pattern baldness.

Similarly...

Rogue cells therapy

Think of all your cancers, Auto-Immune diseases etc. where the bodies own cells are doing something that they shouldn't be - if you have the ability to edit or otherwise target these cells (Nano-bots, special space medicine, targetted inhibitors - you name it) - then you can remove all of these from your world.

Nerve repair

This is a biggie - Spinal injuries, brain injuries (we'll get to that in a min) and other issues where there's been significant damage to nerves, nerve endings and other bits - if you can repair these, you can rule those out...

However - you are at liberty to dictate the complexity, it stands to reason that repairing the nerve endings in say the finger is orders of magnitude far easier than repairing TBI (Traumatic Brain Injury) and so you can have that as your limiting factor.

Stasis

This is probably the most important one - can someone be put into Stasis or suspended animation or Cryosleep or other scenario where someone has suffered a massive and sudden injury that would result in death in minutes or seconds - can they paused until they can get to the appropriate medical centre?

Mental health

Fixing the physical body and fixing a broken mind are not the same thing - and you can have a lot of fun with this. You could make an argument that advances in medical technology has created a whole host of mental problems because the Human mind evolved for small, tribal groups that regularly faced death, disease and war - Just look at the rise of Mental Health issues in the west, when compared to other civilizations.

One can even argue that no technological solution will fix this problem - so that's always a lot of fun.

Finally:

Your Sci-Fi universe can always find ways to be deadly - I'm an Avid WH40K fan and the Space Marines are written to have multiple artificial implants to increase blood clotting, filter out poisons etc. to make them nigh un-killable by regular means - but in universe, the threats out there are so bad and terrible that they are able to be killed.

Things like vaporization from a Plasma weapon - no amount of Medical tech is likely to repair that.