What does Polycythemia refer to?

Polycythemia refers to an increase in the number of red blood cells (RBCs) in the bloodstream. This condition is often associated with hypoxemia, which is a deficiency of oxygen in the blood. When the body senses low oxygen levels, it compensates by producing more red blood cells to enhance oxygen transport. This adaptive response can occur in various scenarios, such as living at high altitudes or having chronic lung diseases.

Recognizing that polycythemia is primarily about the elevation of red blood cell mass helps in understanding its physiological implications. It can lead to increased blood viscosity, which may predispose individuals to hypertension and thrombosis. This condition underscores the body's mechanisms for maintaining homeostasis in response to environmental or physiological stresses.