Improvement is indicated by the patient's ability to maintain normal ______ on less ______.

Improvement is indicated by the patient's ability to maintain normal ______ on less ______.

• A. normal PaO2 on less FiO2
• B. normal SpO2 on more FiO2
• C. normal PaO2 on more FiO2
• D. normal SpO2 on less FiO2

Answer: (A)

Improvement is shown by how well the lungs can oxygenate the blood when you reduce the amount of oxygen you’re giving. PaO2 measures the actual amount of oxygen dissolved in arterial blood, so maintaining a normal PaO2 while using less FiO2 means the lungs are transferring oxygen efficiently and the need for supplemental oxygen has decreased. SpO2 can stay in a normal range even if PaO2 drops due to how hemoglobin saturates, so it’s a less precise gauge of true oxygenation. So the best indicator is normal PaO2 on less FiO2.

Improvement is shown by how well the lungs can oxygenate the blood when you reduce the amount of oxygen you’re giving. PaO2 measures the actual amount of oxygen dissolved in arterial blood, so maintaining a normal PaO2 while using less FiO2 means the lungs are transferring oxygen efficiently and the need for supplemental oxygen has decreased. SpO2 can stay in a normal range even if PaO2 drops due to how hemoglobin saturates, so it’s a less precise gauge of true oxygenation. So the best indicator is normal PaO2 on less FiO2.