One of my favorite orgs that doesn't get enough attention is glia, which maintains a GitHub org filled with open source medical devices such as this stethoscope or this otoscope. All their projects are all licensed under the TAPR Open Hardware License. This is in addition to their actual sending of doctors and medical staff to war zones and underprivileged areas.
You can donate to them directly here:
https://glia.org/pages/support-glias-mission
Or you can sign up as a Patreon member here:
https://www.patreon.com/glia