|Never an easy answer. |
You need to at least provide some scope of work, determine cost either by design analysis or competitive bidding from sources known to do this work or pay a third party to decide the typical costs.
Then you need to search for either individuals or companies to perform this work.
Be sure you have a good contract that covers any contingency to include but not limited to flaws in design, loss of data, loss of protected information, deployment dates and backdoor denial or agreement.
There are a number of companies that specialize in medical applications. You also may with to share your idea and let them sell it to others in a co-op sort of agreement.
From your brief statement we can't begin to direct you.
A Pit Bull is like a gun you can pet. And there is no safety on it.