Hemoglobin (Hb) is the red pigment that contained in the RBCs, its major function is to bind oxygen and transport it to the tissues and to bind CO2 and carry it back from the tissues to the lungs.
Hemoglobin has the same life span of the RBCs, after the engulfing of old RBCs by the reticulo-endothelial cells, the hemoglobin is dissociated into biliverdin, globin and iron, the last two are reutilized in the synthesis of new RBCs. Biliverdin is transported in blood binding to albumin (unconjugated bilirubin).
Physiological factors that affect the RBCs count produce the same effect on Hb concentration.
Hemoglobin concentration can be measured using sahli’s method, cynmethemoglobin method or by blood cells counter.
Hemoglobin concentration is expressed in gram/liter (g/l).