Red Cell Substitutes

Introduction

What are red cell substitutes?

The demand for blood is always more than its supply. Also with the risk of blood-borne infections, efforts for finding an artificial substitute for human blood is going on.

What are the various types of red cell substitutes?

There are 2 main types in use today:

• Fluorocarbons

• Hemoglobin derivatives

What are fluorocarbons?

Perfluorocarbons are synthetic oils with high solubility (oxygen is twenty times more soluble as that in water). These carriers provide oxygen to areas of tissues where red cells cannot reach (fluorocarbons can squeeze through arterial deposits & clots because of its small size) such as myocardial infarctions & stroke. They have also been used in liquid ventilation. For more details - see liquid ventilation.

What are hemoglobin derivatives?

Membrane-free or stoma-free hemoglobin solutions are prepared by gentle lysis of previously washed red cells with hypotonic phosphate buffer. The resultant hemoglobin solution is at a concentration of 6.8 gm/dl. They are useful to maintain basal levels of oxygen in the body in the virtual absence of red blood cells.