Don't have an ICU? you can still have an RRT.
Insufficient staffing, need for physician coverage of the rapid response team, other reasons for alternate models. ED and ICU nurses can be cross-trained to cover each other's units and the RRT. EMS staff can also be used, especially when many also are RNs.
D004636:Emergency Service, Hospital; D006801:Humans; D007362:Intensive Care Units; D010348:Patient Care Team; D010561:Personnel Staffing and Scheduling / Q000458:organization & administration*; D013997:Time Factors; D014481:United States; D000078329:Workforce