Complications following an unnecessary peri-operative plasma transfusion and literature review
An 82-year-old female was scheduled to undergo elective knee replacement surgery secondary to degenerative joint disease. She had no personal or family history of a bleeding diathesis, nor was she on anticoagulation therapy. Pre-operative coagulation studies collected two weeks prior to the planned surgery date were slightly abnormal: prothrombin time (PT) 18.2 s (reference range, 11.7-15.3 s), INR 1.5 (reference range, 0.8-1.2), partial thromboplastin time (PTT) 39.4 s (reference range, 22.7-35.6 s). Her liver function tests and the parameters of her complete blood count from the same sample were all within the normal range. The cause of these coagulation abnormalities was not investigated, and repeat testing was not performed before the day of her surgery. Due to the mildly elevated INR, the patient's hematologist, who was medically managing this patient, recommended that 2 units of plasma should be transfused on the day of her surgery. After transfusion of the first unit of fresh frozen plasma, which was thawed at 37℃ as per standard blood bank protocol and immediately issued for transfusion, on the day of surgery the patient developed widespread hives, hoarseness of her voice, and the subjective sensation of throat closure. Her oxygen saturation was maintained on room air (SpO2≥96% throughout this episode), her vital signs including her blood pressure were stable (temperature 36.5C, heart rate 55-75/min, respiratory rate 18-20/min, systolic blood pressure 130-140 mmHg throughout this episode), and no abnormal breath sounds were appreciated. Once this reaction was identified by the nurses in the pre-operative holding area, the unit physician stopped the plasma transfusion, and 25 mg diphenhydramine, 20 mg famotidine, and 8 mg dexamethasone were administered. No other resuscitative measures were required. Within 2 hours all of these signs and symptoms had resolved. The blood bank investigation for hemolysis, which included a direct antiglobulin test, an inspection of her plasma for free hemoglobin, and a clerical check to ensure the correct unit was issued to the intended recipient, was negative. The transfusion medicine service was consulted and diagnosed this constellation of signs and symptoms as a mild-to-moderate allergic reaction. Due to this transfusion reaction, her surgery was cancelled and rescheduled for the next available operating room time which was 4 weeks later.\nTwo weeks before her surgery was reattempted, pre-operative blood tests again revealed a very slightly elevated INR (1.3) and the cause of this mild abnormality was not investigated. After being made aware of this INR value, the hematologist ordered 1 unit of plasma to be transfused immediately before the surgery. However, due to the patient's previous reaction to plasma, a thromboelastogram (TEG) analysis was performed immediately before the surgery began. Its values were within normal limits, plasma was not transfused, and the surgery was successfully completed utilizing spinal anesthesia with only 75 mL of blood loss. Vitamin K was not administered. The patient was discharged on the second post-operative day.