<prompt> Most common metabolic complication of Blood transfusion is?HyperkalemiaHypercalcemiaMetabolic alkalosisIncreased 2, 3 DPG  <response>: ANSWER: C Metabolic alkalosisREF: Wintrobes Clinical Hematology 12th Edition page 675See APPENDIX-55 below COMPLICATIONS OF MASSIVE BLOOD TRANSFUSIONOne of the significant changes in stored red cells is 2,3-DPG depletion, which is related not to red cell viability but to the ability of the red cells to deliver oxygen.The elevated K content of stored red cells rarely leads to hyperkalemia, but it is a risk in the presence of renal failure, shock with acidosis, or hemolysis. APPENDIX - 55Complications of Massive Blood Transfusion:Massive blood transfusion is defined as transfusion of more than or equal to 10 units of packed RBC.ComplicationCauseEffects of complicationHypothermiaDue to cold blood transfusionPlatelet dysfunction, coagulopathy, cardiac arrhythmias, Hb oxygen affinityAcid base disturbanceMetabolic acidosis lactic acidosisInitially, Accumulation of lactic acid pyruvic acid in stored blood Metabolic alkalosis most commonLater, Conversion of citrate to bicarbonate in liver Hypotension refractoryCitrate intoxication Hypocalcaemiacitrate binds to caVentricular fibrillation, hypotension, myocardial functionHypomagnesaemiaCitrate binds to Mg Hyperkalemia transient applies to rapid transfusionRemoves out of destroyed RRC during storageCardiac arrhythmias especially with coexisting hypocalcemiaHypokalemia applies to slow transfusionK taken back by depleted RBC CoagulopathyFactor deficiencyDilution effectBleeding ThrombocytopeniaDilution effect DICDue to diffusion hypoxia of shock not transfusion per se. ARDS Due to sequestration of micro aggregates fibrin, platelet, WBCs as a result of shock not transfusion per se. 