Responsibilities Intensive Care Unit RNs (ICU RNs) specialize in delivering care to patients in intensive care units of hospitals and healthcare facilities. ICU RNs evaluate the patient's conditions, administer treatment, and provide constant support during recovery. ICU RN job responsibilities include, but are not limited to: Evaluate and order diagnostic tests and administer intravenous fluids and medications Respond to life-threatening situations using nursing standards and protocols for treatment Ensure ventilators, monitors, and other types of medical equipment function properly