What does hypoxemia specifically refer to?

Hypoxemia specifically refers to an inadequate amount of oxygen in the blood. This condition is typically quantified by measuring the partial pressure of oxygen in arterial blood (PaO2) or the oxygen saturation of hemoglobin (SaO2). Hypoxemia can occur due to various reasons, including respiratory disorders, altitude, or specific conditions that impair oxygen delivery to the bloodstream.

In contrast, inadequate perfusion of tissues relates to the overall blood flow reaching the tissues, which may be due to issues like shock or heart failure. Impaired gas exchange in the lungs refers to the specific mechanism by which oxygen and carbon dioxide are exchanged, commonly seen in conditions like pneumonia or chronic obstructive pulmonary disease (COPD). Overall oxygen deficiency in the body encompasses both systemic issues and could be due to several factors, including hypoxemia, but does not specifically refer to the oxygen content of the blood itself.