Which departments in the hospital are considered critical care?

Icu, ER, PACU and OR: as above.

Many: It may depend on which ICU your loved one is in. For adults, critical care services can be rendered by anesthesiologists, surgeons, pulmonologist, cardiologists, ER doctors and those with advanced training in critical care after internal medicine training.

ICU: Hi. The intensive care unit may be run by various specialists: medical ICU is usually run by pulmonary critical care, cardiac ICU is run by cardiology, surgical ICU is run by anesthesiologists with surgical input, pediatric ICU and neonatal ICU are run by pediatric intensivists, neurological ICU is run by neurological intensivists. What ICU a patient ends up in depends on patient problem.