Blockchain is also not a guarantee of privacy. Every transaction in a blockchain is publicly viewable by everyone who has access to it. The FBI has demonstrated the ability to track transactions. It's not easy, but it is also not as advertised.

Escrow is managed by a neutral 3rd party. This prevents the patients from being held hostage.

The hardware may require significant external processing before being sent back. That's what it sounds like.

Forgot to mention that there is nothing magical about cloud services. If the entirety of the software is escrowed, a developer should be able to get it up and running. It gives the patient a chance.

The hardware doesn't need to be open sourced. Place the software in escrow, including everything needed to install, maintain and run it, including any microcode on the devices. Should the company go belly up, release the software to the patients and open source it. If you have the source code, you have everything you need to continue providing the service. You may not be able to build new devices, or enhance the hardware, but you'd be able to keep the existing base up and running, and, possibly, provide enhancements via software updates.

All medical software that directly impacts a patients quality of life should be required to be put into escrow with each patient the recipient. Should the company fail or discontinue the product for any reason that would result in a reduced quality of life for the patient, the patient should receive the software along with, at least, the right to deploy and modify it for their own personal use. I would go even further and say that the software should also be immediately placed into open source to allow others to host and maintain the software on the patients' behalf.

The neurosurgery is done. Apparently what they need is a server to host the software. That's not brain surgery.

He was standing in an open field west of a white house, with a boarded front door. There was a small mailbox there.