Hemoglobin Is a Vital Determinant of Arterial Oxygen Content in Hypoxemic Patients with Pulmonary Arteriovenous Malformations.

Rationale: Pa and Sa are commonly measured in respiratory practice, but arterial oxygen content (Ca) refers to the volume of oxygen delivered to the tissues per unit blood volume. Ca is calculated from Sa and the hemoglobin concentration in blood, recognizing that each gram of hemoglobin can transport approximately 1.34 ml of oxygen when fully saturated.