One of the main reasons why a patient is admitted to an ICU is for delivery of mechanical ventilator. Monitoring a patient in mechanical ventilator has many clinical applications: Enhance understanding of pathophysiology, aid with diagnosis, guide patient management, avoid complications and assessment of trends.
Most of modern Intensive Care Ventilators have basic monitoring tools. There are also monitors that work independently of the ICU Ventilator, which allow to measure patients after the Critical Care Ventilator has been removed, such as a T tube test.