A group of persons are rushing into the hospital with a severely injured person who had severe blood loss due to road traffic accident and he was taken into the ICU and doctors were working hard to save his life by washing his wounds, performing surgeries, infusing him medications and BLOOD TO MAINTAIN HIS CIRCULATION. Does this blood stored in bags can effectively do its work??????
In other scenario again a group of people are moving into the nearby hospital with happy faces to donate their blood to save life. Is their belief true? As we all know blood bank is one of the most important aspect of an hospital as all important surgeries and clinical conditions require large amount of blood transfusion to maintain both hemostasis and homeostasis of the patient does this blood which is stored for almost 42 days is entirely safe for the patients after transfusion?
This question when interrogated has given negative answer. You may wonder but many studies states that there is great increase in potassium levels in the stored blood increased from a normal value of 4.2 mEq/L to 9.2 mEq/L within a week . In case of packed RBC stored with CPDA(A widely used anticoagulant) the mean potassium concentration was 6.4 meq/l and it raised to 15.4 meq/l within a week. This dramatic change in the potassium levels is due to DEFECTIVE FUNCTIONING OF SODIUM POTASSIUM ATP Pasepump. As we all know this pump is necessary to maintain the homeostasis of all cell and it maintains the ionic balance so any defect in the pump leads to ionic imbalance. The red blood cells are stored at a temperature of 2 to 4 degree Celsius. And this very low temperature causes its derangement thereby increasing potassium levels. And studies also says that it reaches about 22.8 meq/l after 21 days in case of whole blood and 32.8meq/l after 21 days in case of whole blood. So imagine if such a blood loaded with potassium is given to the patient who is critically ill what happens?
A study was conducted among 125 patients in critical care unit which included patients suffering from septic shock ,non st elevated myocardial infarction, acute git bleeding and DIC and vaginal bleed. There pre and post transfusion potassium levels are measured .the mean change of potassium was from 3.9 to 4.3 meq/l after transfusion. Four percent of patients had post transfusion hyperkalemia and a rise in blood potassium level was noted in 73 patients. Some studies suggest that the sodium potassium pump is derangement is not that much severe when stored at room temperature but this again increases another component lactate in the stored blood . so what best can we do is to do RBC washing which is a very simple method of reducing potassium prior to transfusion, using only fresh blood for major surgeries and neonates who require passive transfusion for hyper bilirubinemia and in cardio pulmonary bypass. Lets take these few and simple steps to ensure the fast recovery of our patients whose health is most important to us.
A budding doctor ANJANA RAJAGOPALAN