Plasma

Plasma can be obtained in two ways - from whole blood donation, from which about 250 ml of plasma is collected. Or as apheresis plasma, which is collected from a single donor. This can be up to three-quarters of a litre of plasma. Some single donor plasma is immediately frozen in 250ml portions as quarantine plasma and stored for at least 4 months. If the donor returns to donate and the test results are OK, it can be released.

The plasma most commonly used in Austria is Octaplas. The company Octapharma (in this case) buys frozen plasma from the blood banks, and after thawing, these plasmas are pooled in hundreds, divided according to blood group. Therefore, one must also pay attention to the blood group transfusing plasma. With plasma, the "universal blood group" is AB - which has no isoagglutinins.

For one, plasma is used as a substitute for clotting factors as a whole. On the other hand, individual coagulation factors are obtained from plasma according to specific fractionation methods. There is a growing trend, especially in trauma patients, to no longer use plasma but to regulate coagulation from the beginning by using individual clotting factors. 

Especially in trauma patients, many hospitals still have a "transfusion scheme" for how a bleeding trauma patient is supplied with blood products (e.g., 2 EC, 1 TC and 1 plasma or 3:1:1). There are many variations. Still, none of these schemes is based on study results - they are much more "protocols by guesswork".

 

The studies on this topic show at least one thing: plasma should be used as sparingly as possible. But if used, it should be transfused with the right amount from the beginning.

 

 

Like all blood products, plasma is intended for immediate transfusion. But except in shock rooms and operating theatres, the reality is different. Like all transfusion products, plasma can sit around too long before transfusing. This is a separate issue, but once pierced with a transfusion stick, they must be transfused within 4 hours like all other blood products.


Frozen quarantine plasma.

Currently, there is no blood depot in Austria that stocks thawed/liquid plasma. But the requests for it are coming with increasing frequency.

Octaplas is the most commonly used product in Austria. The plasma from whole blood donations is sold to the industry - there, it is pooled and pathogen-inactivated and only then split into separate bags again. The advantage is that the individual variations in the active factors are equalised in this way.


Rekonvaleszent-Plasma (Covid-19)

Since Corona, even lay people know that plasma can be used as a medicine. How does it work? It is a passive vaccination. People who have been sick with Covid-19 have antibodies in their blood against SARS-CoV2 - the virus that causes Covid. The idea is that these antibodies could be given to a sick person to support their own immune defence. Plasma containing the antibodies is taken from covid convalescents. This plasma can be provided directly to a patient. It is a good idea, but it doesn't work as expected.

We offer Covid plasma to patients in our clinic. However, it has not made a considerable difference when Covid-19 plasma has been used. It may also be because it is often administered too late. And after patients get very intensive treatment, it is usually hard to tell what helped. My observations align with the results of a study with over 300 patients, one-third of whom did not get Covid plasma and two-thirds did. No significant differences in outcome were observed between the two groups. The study, "A Randomized Trial of Convalescent Plasma in Covid-19 Severe Pneumonia", was published in the New England Journal of Medicine at the end of November 2020.

Last update on 13.08.2023.