of prophylactic platelet transfusion altogether, while others have recommended thresholds ranging from 10 000/mm3 to 100 000/mm3 for patients at risk of bleeding.Answer: DHolcomb, J.B., Tilley, B.C., Baraniuk, S., et al. (2015) Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma: The PROPPR randomized clinical trial. J Am Med Assoc , 313 (5), 471–482.Hébert, P., Wells, B., Blajchman, M., et al. (1999) A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. N Engl J Med , 340 (6), 409–417.10 A 75‐year‐old woman is admitted to the intensive care unit following coronary artery bypass grafting. There were no complications during her surgery, and she is hemodynamically stable. Her postoperative labs reveal a hemoglobin of 8.1 g/dL. Which of the following supports implementing a restrictive transfusion strategy in this patient?Restrictive strategies reduce the risk of transfusion related reactions.Restrictive strategies reduce overall morbidity.Restrictive strategies improve survival.Restrictive strategies reduce the incidence of postoperative myocardial infarction.Restrictive strategies have demonstrated improvement in end‐organ oxygen consumption.In a recent trial involving patients undergoing cardiac surgery, restrictive red‐cell transfusion strategy (hemoglobin threshold of < 7.5 g/dL) was noninferior to a liberal strategy (hemoglobin threshold of < 9.5 g/dL in the operating room or intensive care unit) in regard to death and major disability (including myocardial infarction, stroke, and new‐onset renal failure with dialysis) among postoperative patients who had a moderate to high risk of death. These outcomes were achieved with fewer units of blood being transfused. Contemporary evidence‐based guidelines for all surgical patients also discourage liberally transfusing packed red blood cells (PRBCs) in most cases when bleeding has been controlled. Although transfusion of PRBCs was traditionally used to improve oxygen delivery, multiple studies have failed to demonstrate an improvement in end‐organ oxygen consumption with transfusion. This may be partially explained by the decreased deformability and adverse microcirculatory effects of stored red blood cells. Risks associated with RBC transfusion include fluid overload, fever, acute transfusion reaction, increased rate of multi‐organ failure, increased infection rates, transfusion‐associated immunomodulation, human error with incorrect blood administration, transfusion‐related acute lung injury (TRALI), and viral transmission.Answer: AMazer, C.D., Whitlock, R.P., Fergusson, D.A., et al. (2017) Restrictive or liberal red‐cell transfusion for cardiac surgery. N Engl J Med , 377 (22), 2133–2144.Mirski, M.A., Frank, S.M., Kor, D.J., et al. (2015) Restrictive and liberal red cell transfusion strategies in adult patients: reconciling clinical data with best practice. Crit Care Med , 19 (1), 1–11.
11 Given that mortality is improved with the rapid activation of massive transfusion protocol (MTP), but complications from unnecessary exposure to blood products can be devastating, prediction tools can be used to aid clinicians in the careful decision to initiate massive transfusion. Which of the following is not a metric of the Assessment of Blood Consumption (ABC) score used to trigger MTP?Heart rate > 120 per minuteSystolic blood pressure < 90 mmHgGlasgow Coma Scale < 9Positive FAST (focused assessment with sonography for trauma)Penetrating injury to the torsoThere are no uniformly accepted criteria for activating an MTP. Several clinical factors have been validated as individual predictors of massive transfusion. The ABC score consists of four such factors (pulse > 120, SBP < 90, positive FAST, and penetrating torso injury), each assigned one point. A score of two or more warrants MTP activation. The ABC score overestimates the need for transfusion, with a positive predictive value of 50–55%, meaning that 45–50% of patients in whom MTP is activated will not need a massive transfusion. However, the ABC score is excellent at identifying patients who will not need massive transfusion, with a negative predictive value of less than 5%. Massive transfusion has been variably defined (e.g., ≥10 units packed red blood cells [PRBCs] over 24 hours, ≥3 units PRBCs per hour). Survival is improved by the timely administration of blood products in proper ratios.Answer: CNunez, T.C., Woskresensky, I.V., Dossett, L.A., et al. (2009) Early prediction of massive transfusion in trauma: Simple as ABC (assessment of blood consumption). J Trauma , 66 (2), 346–352.Callcut, R.A., Cotton, B.A., Muskat, P., et al. (2013) Defining when to initiate massive transfusion: a validation study of individual massive transfusion triggers in PROMMTT patients. J Trauma Acute Care Surg , 74 (1), 59–65.
12 A 68‐year‐old intubated woman is being resuscitated in the intensive care unit after presenting in hemorrhagic shock following multiple episodes of hematemesis. She has received 6 units of packed blood cells (PRBCs) over the past 12 hours and her provider decides to administer plasma and platelets to balance her resuscitation efforts. What is the rationale for administering apheresis platelets over pooled platelets in this scenario?Apheresis platelets have reduced risk of bacterial and viral contamination.Mortality is improved with use of apheresis platelets.Apheresis platelets are readily available and cost effective.Apheresis platelets have reduced risk of transfusion‐related acute lung injury.Apheresis platelets have reduced risk of hemolytic transfusion reaction.A high ratio of platelets to PRBCs is defined variably in previous studies as approximately one unit of apheresis platelets for every 6–10 units of PRBCs transfused. Additionally, the PROPPR trial showed faster hemostasis and fewer deaths from hemorrhage in the group treated with a higher ratio of plasma and platelets to PRBCs. When massive transfusion is required, platelets should be transfused in an appropriate ratio without waiting for clinical laboratory results to confirm low platelet counts. No prospective study has demonstrated survival difference between apheresis and pooled donor platelets. One unit of apheresis platelets is obtained from a single donor, while pooled platelets are combined from six to eight donors. As a result, pooled platelets have a higher risk of bacterial contamination as well as viral transmission; however, there is no difference in transfusion‐related lung injury. There is no difference in hemolytic transfusion reactions between the two.Answer: AHolcomb, J.B., Tilley, B.C., Baraniuk, S., et al. (2015) Transfusion of plasma, platelets, and red blood cells in a 1:1:1 vs a 1:1:2 ratio and mortality in patients with severe trauma: The PROPPR randomized clinical trial. J Am Med Assoc , 313 (5), 471–482.Inaba, K., Lustenberger, T., Rhee, P., et al. (2011) The impact of platelet transfusion in massively transfused trauma patients. J Am Coll Surg , 211, 573–579.
13 An 85‐year‐old man is admitted to the intensive care unit following endovascular repair of a ruptured abdominal aortic aneurysm. He required a total of 12 units packed red blood cells intraoperatively. His postoperative labs reveal a calcium level of 6.1 mg/dL. Which of the following is not a consequence of his hypocalcemia?Muscle tremorsProlonged QTHypotensionArrythmiaT wave inversionHypocalcemia is the most common abnormality associated with massive transfusion, occurring in >90% of patients receiving a massive blood transfusion. Stored blood is anticoagulated with citrate, which binds calcium and causes hypocalcemia after large‐volume blood transfusion. Complications of hypocalcemia include prolonged QT, decreased myocardial contractility, hypotension, muscle tremors, pulseless electrical activity, and ventricular fibrillation. T wave inversion is classically associated with hypokalemia.Answer: ESihler, K. and Napolitano, L. (2010) Complications of massive transfusion. Chest , 137, 209–220.
14 A 56‐year‐old man with a history of chronic atrial fibrillation is brought to the emergency department after being found down. He is unresponsive and promptly intubated. His blood pressure is 75/25 and there are no obvious external signs of trauma. A chest x‐ray is performed for endotracheal tube confirmation and massive free air is noted under the bilateral hemidiaphragms. Stat laboratory results are most notable for white blood cell count of 23, hemoglobin of 12, hematocrit of 30, platelet count of 250, and an international normalized ratio of 3.1. Plans are made for emergent abdominal exploration. What is the fastest way to correct his coagulopathy in preparation for his procedure?Activate the massive transfusion protocol.Administer 4‐factor prothrombin complex concentrate.Transfuse fresh frozen plasma.Transfuse fresh frozen plasma and administer vitamin K.No preoperative reversal is indicated as the case is a surgical emergency.Coagulopathy can delay or complicate surgical diseases that require emergent surgical treatment. Historically, warfarin reversal was achieved with rapid administration of fresh frozen plasma (FFP). In 2013, the US FDA approved a 4‐factor prothrombin complex concentrate (PCC) for urgent warfarin reversal. PCC alone reduces INR and time to surgery effectively and safely in coagulopathic patients without an apparent
