Certified Clinical Transplant Nurse (CCTN) Practice Exam

Maintaining a PF (PaO2/FiO2) ratio of 250 or greater is a critical goal of pulmonary support in patients, particularly those experiencing respiratory distress or conditions that compromise gas exchange. The PF ratio is an important measure used to evaluate the degree of hypoxemia in patients, helping to determine the severity of respiratory failure. A PF ratio of 250 or above generally indicates that the lungs are still functioning reasonably well, allowing for adequate oxygenation of the blood.

By aiming for this PF ratio, healthcare providers can assess the effectiveness of therapeutic interventions such as supplemental oxygen, mechanical ventilation, or other forms of respiratory support. A higher PF ratio is associated with better pulmonary function and improved outcome potential, making it a target in managing patients with acute lung injury or acute respiratory distress syndrome (ARDS).

In contrast, increasing shunting effects, achieving a negative fluid balance, and lowering oxygen saturation would not be desirable goals in pulmonary support, as they would typically lead to worsened oxygenation and respiratory compromise.