Hi @Aviad:
Welcome to the family.
This is a very interesting use case, that few people in the community have attempted, it seems. The problem is that the OMOP CDM is not geared towards it, and you will probably have to do your own Expansion of the Model (what you call minor modifications). For example, right now there is no support of orders (issue, follow up, fulfillment, cancellation etc.), no support for scheduling, and no support for identifiable information of patients, providers and organizations (names, phone numbers etc.). The other problem is that the model isn’t transactional, or semi-transactional. All entities tend to have start and end dates, stretching over time. So, when a patient undergoes a treatment or has a condition, you will have to go back to the same record and change the end date until it is over. While that is happening there is no indication that something is still ongoing (see the debate about this problem for visits here, but it also got debated later). Also, often the end date is not available, even when this is technically not possible (see the debate about this problem also for visits here). But so far this has been discussed as a day by day problem, rather than second by second.
Let’s see if somebody wakes up from vacation time who has more experience. Good luck to you.