Lifeline Emergency Response Lifeline Emergency Response is the key to ensuring great help is close by. Critical care nurses provide care to patients with serious, complex, and acute illnesses or injuries that require very close monitoring and extensive medication protocols and therapies. Tales for an accelerated culture. Good Luck, and thank you for your post. Intellectual and developmental disabilities nurses provide care for patients with physical, mental, or behavioral disabilities; care may include help with feeding, controlling bodily functions, sitting or standing independently, and speaking or other communication. RNs also can choose to work with a well-defined population, such as geriatric nurses, who work with the elderly.