Blood donors are essential in medicine today, but it would be a great step not to need donors. There are many reasons for this: sometimes there are problems with access to donated blood, that blood is quickly damaged, etc. That is why they try to produce artificial blood. And they have created more than one. The problem is that that blood has to be a reliable substitute for real blood and, according to one study, actual artificial blood is not entirely reliable.
Commercial use of artificial blood has not yet been approved in Europe and the United States, but numerous clinical trials are underway. Many groups are working on this, so at a clinical institute in Maryland, United States, they wanted to collect the results of several clinical sessions for a statistical study. The results are clear: the use of artificial blood causes too many cases of heart and death, 15% more than with real blood.
This is only a statistical analysis and some contrary opinions have been heard. But, according to the researchers, it is worth looking for the reasons for this statistic. One might be that artificial blood hemoglobin captures nitric oxide instead of capturing oxygen. This substance causes a dilation of the blood vessels. However, this explanation is only a hypothesis; experts do not know what is really happening.