Posted January 15, 20169 yr comment_63680 Is it correct to prepare blood unit by using a hemolysis blood sample ?! if reverse group test work properly ? or we must ask another sample ?
January 17, 20169 yr comment_63696 Do you use EDTA blood samples? We use EDTA blood samples and Anti-IgG gel cards. We don't reject hemolyzed blood samples unless black text on white paper cannot be read through the hemolyzed plasma.
January 18, 20169 yr comment_63701 I think you have to be a bit pragmatic. If the sample comes from a generally healthy adult and the sample is haemolysed simply because of poor phlebotomy technique, then I would say, ask for another sample. But you don't really want to insist if the sample comes from a young child or a very elderly person with poor veins - or, of course, if the haemolysis reflects the true state of the patient's blood at the time
January 18, 20169 yr comment_63702 The only problem I can see (well, two problems potentially), is that one is supposed to check for hemolysis as a sign of a positive reaction when doing basic tests like ABO and screens. Also, as comparing the character of pre- and post- transfusion specimens is part of a possible transfusion reaction workup, there is a potential problem there, too. Scott
January 18, 20169 yr comment_63704 I would agree with your first point Scott, but only because the sample being used is a plain tube, and, therefore, the liquid phase would be serum, rather than plasma. If, on the other hand, the sample was in an EDTA anticoagulated tube, and the liquid phase would, therefore, be plasma, you no longer see in vitro haemolysis, as EDTA will chelate the Ca++, Mn++ and Mg++, all of which are required as cofactors at the beginning of the classic complement pathway. I certainly agree with your second point, unless, as Anna says, there is in vivo haemolysis in the original sample (which is very often seen in cases of CHAD, even if the sample is kept at 37oC).
March 7, 20187 yr comment_72725 On 18/01/2016 at 12:58 PM, Malcolm Needs said: I would agree with your first point Scott, but only because the sample being used is a plain tube, and, therefore, the liquid phase would be serum, rather than plasma. If, on the other hand, the sample was in an EDTA anticoagulated tube, and the liquid phase would, therefore, be plasma, you no longer see in vitro haemolysis, as EDTA will chelate the Ca++, Mn++ and Mg++, all of which are required as cofactors at the beginning of the classic complement pathway. I certainly agree with your second point, unless, as Anna says, there is in vivo haemolysis in the original sample (which is very often seen in cases of CHAD, even if the sample is kept at 37oC). Hi Malcolm Can you expand on 'no longer see in vitro haemolysis' in EDTA samples. So if the patient had a transfusion reaction with in vivo haemolysis are you saying in an EDTA sample you would not see this haemolysis? Thanks Edited March 7, 20187 yr by Tabbie spelling
March 7, 20187 yr comment_72726 On 1/15/2016 at 3:29 PM, emadlabs said: Is it correct to prepare blood unit by using a hemolysis blood sample ?! if reverse group test work properly ? or we must ask another sample ? I will use the hemolyzed for testing unless it has gross hemolysis. We use gel and the cell button/agglutination is rarely obscured due to hemolysis. I rarely have had to ask for another sample.
March 7, 20187 yr comment_72727 1 hour ago, Tabbie said: Hi Malcolm Can you expand on 'no longer see in vitro haemolysis' in EDTA samples. So if the patient had a transfusion reaction with in vivo haemolysis are you saying in an EDTA sample you would not see this haemolysis? Thanks The problem would be with hemolyzed samples due to a hard draw. (We see this quite often in our EDTA specimens.) In which case, it would not matter whether it's serum or plasma, it could be a problem down the line as far as interpretation of tests go. Scott
March 7, 20187 yr comment_72728 Just as a side note, most of the hemolysis I saw was in tubes that were collected by a nurse when they started an IV. Not sure what the exact correlation was but that was the case more often than not.
March 7, 20187 yr comment_72730 2 minutes ago, John C. Staley said: Just as a side note, most of the hemolysis I saw was in tubes that were collected by a nurse when they started an IV. Not sure what the exact correlation was but that was the case more often than not. Oh God, yes. Those of us working in hospitals have to contend with non-Lab draws every day. Part of our pre-analytical responsibilities is to check for stuff like this before processing specimens. Scott
March 7, 20187 yr comment_72732 2 hours ago, Tabbie said: Hi Malcolm Can you expand on 'no longer see in vitro haemolysis' in EDTA samples. So if the patient had a transfusion reaction with in vivo haemolysis are you saying in an EDTA sample you would not see this haemolysis? Thanks No, what I meant was that certain antibodies (some examples of anti-H from a true Oh individual, most examples of anti-Vel, most examples anti-PPkP1 from pp individuals and some examples of anti-I from ii adults, together with some examples of anti-Jka and anti-Lea, plus, of course, some examples of anti-A, anti-B and anti-A,B) would cause antigen positive red cells in an antibody identification test to haemolyse, IF serum from a clotted sample was used (hence, in vitro tests), but if EDTA plasma was used, you would not see this haemolysis. In the good old days, seeing haemolysis with all the red cells of an antibody panel, when using serum from a clotted sample, gave us a clue that we were dealing with one of the above antibody specificities (except, of course, the ABO antibodies - because the panel cells were all group O). Nowadays, with the samples almost always being EDTA, we no longer have that clue!
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