I think you need to narrow it down to what type of patient room it is; long term, domiciliary, or nursing hoome has different requirements than general in-patient. The ASHRAE HVAC Design Manual for Hospitals and Clinics recommends no wet coil inside the room for inpatient, all environment control by air side. For nursing home/domiciliary, you can drop room air changes from 6 to 4 is using supplemental heat. If the outside air is through a fcu, then O&M bill goes up. If the OA is through the AHU, then you need to provide all ACH from the DOAS. I'd prefer (and am doing now) to put 4 ACH through a DOAS and use an energy recovery wheel, especially when the facility includes bed pan washers. That seems to please the infection control people and is acceptable to the energy engineer (at least here).
For a large hospital, then need for perimeter heating/cooling becomes an issue, and a fcu has advantages.