Should the therapist perform a patient-ventilator check in addition to regularly scheduled intervals dictated by patient acuity? I. whenever the Fio2 is changed II. before an arterial blood sample is obtained III. in advance of compliance measurements IV. immediately after airway resistance measurements

A. I, IV only
B. II, III only
C. II, III, IV only
D. I, II, III, IV

?ANS: B
A. Incorrect response: See explanation B.
B. Correct response: A patient-ventilator system check should be done: (1) before obtaining arterial blood samples, (2) before measuring respiratory mechanics data, (3) before performing hemodynamic measurements, (4) after a change of ventilator settings (except Fio2), (5) after a deterioration in patient condition, and (6) anytime the performance of the ventilator is in question.
A patient-ventilator system check is unnecessary every time the Fio2 is changed. However, a system check is warranted each time any other ventilator setting is altered. The system check needs to done before the airway resistance value is measured, not after.
C. Incorrect response: See explanation B.
D. Incorrect response: See explanation B.