The admitting doctor in the critical care unit decides when you need to be in a critical care unit. For example, a patient arrives in the emergency room, with complex medical or surgical issues, that require specialized intravenous medications, mechanical ventilation, or close monitoring. That emergency room doctor will contact the critical care doctor and discuss the plan of care. Based on this information, the critical care doctor will admit this patient into the critical care unit. Critical care covers a wide variety of specialized doctors, such as cardiologists, nephrologists, pulmonologists, and neurosurgeons. Any of these doctors, who have critical care admitting privileges, decides when a patient needs specialized critical care.