Red blood cell oxygen has been released the resulting deoxyhemoglobin is of a dark red burgundy color. However, blood can appear bluish when seen through the vessel wall and skin. Pulse oximetry takes advantage of the hemoglobin color change to directly measure the arterial blood oxygen saturation using colorimetric techniques. Hemoglobin also has a very high affinity for carbon monoxide, forming carboxyhemoglobin which is a very bright red in color. Flushed, confused patients with a saturation reading of 100% on pulse oximetry are sometimes found to be suffering from carbon monoxide poisoning. Having oxygen-carrying proteins inside specialized cells (as opposed to oxygen carriers
Mean corpuscular hemoglobin Mean corpuscular hemoglobin The mean corpuscular hemoglobin , or "mean cell hemoglobin" (MCH), is the average mass of hemoglobin (Hg) per red blood cell (RBC) in a sample of blood. It is reported as part of a standard complete blood count. MCH value is diminished in hypochromic anemias. It is calculated by dividing the total mass of hemoglobin by the number of red blood cells in a volume of blood. MCH=(Hgb*10)/RBC A normal MCH value in humans is 27 to 31 picograms/cell. The amount of hemoglobin per RBC depends on hemoglobin synthesis and the size of the RBC. The MCH