2 2 11 Analyse And Present Information From Secondary Source

The problems of using real blood
- Shortage of real blood
- It has to be ‘cross-matched’. This is because, if you receive the wrong type of blood, it can be fatal. This is a great disadvantage in emergency situations.
- It has to be free of infectious agents. Only blood that is free of bacteria and infectious agents (such as HIV) can be used. Testing the blood is costly.
- It has a short shelf-life. Because red blood cells only survive for 3 months, the blood has a short life span (blood can only survive for 3-4 weeks).

Some proposed replacements for blood
- Perflurochemicals (perflurocarbons):
o Synthetic and inert, are completely sterile
o Cheap to produce, compared to using real blood.
o Can dissolve 5 times more oxygen than blood.
o Free of biological materials, therefore no risk of infections
o BUT - must be combined with other materials to mix in with the bloodstream (e.g. lecithin).
- Haemoglobin Based Oxygen Carriers (HBOCs):
o Made from haemoglobin extracted from red blood cells
o Haemoglobin is not contained in membrane - cross matching unnecessary
o Can be stored for a long time
o BUT - haemoglobin tends to oxidise to a different form, break down, and can no longer carry oxygen.
- Dextrose Solution:
o Made of 4% glucose solution in a fluid with equal salinity to blood
o Only used to restore blood pressure after accidents.

Advantages of artificial blood
- They can be sterilized
- Can be stored for long periods of time
- No need to cross-match blood (as there are no cell membranes)
- No risk of infection

Need for research
- Due to the shortages of the use of real blood
- Current drawbacks in artificial blood