Arterial-alveolar oxygen Partial pressure ratio

a/A PO2 Rto

Definition

The arterial/alveolar oxygen tension ratio, also known as a/APO2, is a measure of gas-exchange. While it was originally believed to be less affected by the fraction of inspired oxygen (FiO2) compared to other measures such as the alveolar-arterial oxygen tension difference (PAO2-PaO2), the a/APO2 has been found to be somewhat dependent on FiO2, especially with higher degrees of pulmonary shunting. [PMID: 3742320]

ABG; ALV; ART; Art bld; Art blood; Arterial; Arterial blood; Blood arterial; Calc; Calculation; Lung; O2; O2 A; Point in time; PULMONARY; Pulmonology; QNT; Quan; Quant; Quantitative; Random; Respiratory; tO2