Monday 27 September 2010

My week of CPD - 21st - 25th Sept 2010

During this week I was reading the BCSH transfusion guidelines for neonates and older children as part of the study for my BBTS certificate. I became a little confused when the guidelines told me that if RhD positive FFP was given to an RhD negative girl, prophylactic anti-D would have to be given as there was sufficent red cell stroma in the FFP to provoke RhD sensitization. This advice contradicted the advice in the adult FFP BCSH guidelines that state the red cel stroma left in FFP following the freeze/thawing processes was not immunogenic and therefore RhD positive FFP could be given to a RhD negative female of child bearing age without the risk of sensitization and therefore prophylactic anti-D immunoglobulin was not required.

I e-mailed BC about it and he felt that the neonatal guidelines were incorrect. We discussed it the following day and I showed him the relevant paragraphs in each of the guidelines. He approached GE with the evidence and her feelings were that the neonatal guidelines were wrong. Both guidelines were written in 2004. BC is now to take the matter higher! Surely I can't be the only one to have picked up on this ?error. BC will feed back to me on what he finds out.

This week, we were proving blood for a 16 year old acute lymphobastic leukaemia (ALL) patient who is shared care with Kings College Hospital in London. With the first unit of blood she was transfused, she developed a rash up her arm, spreading from the blood infusion site. The transfusion was stopped and she was investigated for a ? transfusion reaction. No serelogical evidence of Tx reaction could be demonstrated. She then proceeded to be transfused with a second unit of blood, again, she suffered a reaction to the transfused unit and again the transfusion was stopped. The transfsuion practitioner reviewed her case and contacted the consultant at NHSBT for advice. The concern was that this patient was suffering allergic reactions to the transfusion and that they may develop into severe anaphylactic reactions. I learnt that these reactions can happen when the patient has antibodies to 'foreign' white blood cells in the transfused unit, or, if the patient does not produce their own IgA antibodies, they can produce anti-IgA antibodies.

A reaction to white cells in a unit of packed red cells is rare as all packs of red cells are leucodepleted i.e. the majority of white cells have been removed. Individuals who do not produce their own IgA antibodies are also extreemly rare. Patient specimens were referred to NSHBT to determine if our patient had white cell or anti-IgA antibodies. In the mean time, the NHSBT consultant advised that any further transfusions would require washed red cells. It fell to me to order two units of washed red cells, a task I had never under taken before. The units can be ordered using a non-standard blood product request form. I requested two units of group specific washed red cells and had to specify the requirement for them to be K- CMV-. I contacted Tooting, who advised that the red cells would be washed at Brentwood and sent directly to us. When red cells are washed, the blood pack is opened and the cells are washed in saline. Because the pack has been opened, it is no longer sterile and there is a high risk of bacterial contamination. The shelf life of the units is therefore reduced to 24 hours from the time of washing. The washing had to be arranged to take place as late in the day as possible, so that they could be transported from Brentwood to Ashford, be crossmatched and ready for transfusion early the following morning, to give the ward staff sufficent time to complete the transfusion before expiry of the units. Communication with NHSBT and Padua ward was key.

All went smoothly, the transfusion was completed within the 24 hour timeframe and the patient suffered no adverse reactions to the washed red cells. The results from her blood tests showed no white cell or anti-IgA antibodies were present so a cause for the reactions remains unknown.

Thursday 23 September 2010