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Surgical Critical Care and Emergency Surgery


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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 increased risk of thromboembolic events, when compared to FFP use alone.Answer: BGoldstein, J.N., Refaai, M.A., Milling, T.J., et al. (2015) Four factor prothrombin complex concentrate versus plasma for rapid vitamin K antagonist reversal in patients needing urgent surgical or invasive interventions: a phase 3b, open‐label, non‐inferiority, randomized trial. Lancet ,385 (9982), 2077–2087.Younis, M., Ray‐Zack, M., Haddad, N.N., et al. (2018) Prothrombin complex concentrate reversal of coagulopathy in emergency general surgery patients. World J Surg , 42 (8), 2383–2391.

      15 A 26‐year‐old man is admitted to the surgical intensive care unit after an automobile struck his motorcycle. He is hemodynamically stable and found to have a grade 3 splenic laceration with no active extravasation and a left, displaced, mid‐shaft fracture of the humerus. The fracture was reduced and leg placed in traction while he is being observed for his splenic laceration. Suddenly he becomes confused with progressive shortness of breath and hypoxia requiring intubation. A chest X‐ray demonstrates diffuse bilateral infiltrates. Labs reveal a platelet count is 75 000/mm 3 , prothrombin time of 19 second, partial thromboplastin time of 50 second, oozing is noted from intravenous access sites, and blood is suctioned from his endotracheal tube. Which of the following test results would be consistent with the diagnosis of disseminated intravascular coagulation?Increased antithrombin levelElevated fibrin degradation productsDecreased bleeding timeElevated fibrinogen levelDecreased D‐dimerDisseminated intravascular coagulation (DIC) is characterized by widespread microvascular thrombosis with activation of the coagulation system and impaired protein synthesis, leading to exhaustion of clotting factors and platelets. The end result is organ failure and profuse bleeding from various sites. DIC is always associated with an underlying condition that triggers diffuse activation of coagulation, most commonly sepsis, trauma with soft tissue injury, head injury, fat embolism, cancer, amniotic fluid embolism, toxins, immunologic disorders, or transfusion reaction. In this case, the patient appears to meet criteria for fat embolism syndrome which likely triggered his DIC. There is no single laboratory test that can confirm or rule out a diagnosis of DIC. A combination of tests in a patient with an appropriate clinical condition can be used to make the diagnosis. Low platelet count, elevated fibrin degradation products or D‐dimer, prolonged prothrombin time, and low fibrinogen level are all consistent with a diagnosis of DIC.Answer: BLevi, M . (2007) Disseminated intravascular coagulation. Crit Care Med , 35 (9), 2191–2195.

      16 A 61‐year‐old man is admitted to the surgical intensive care unit with a diagnosis of ischemic colitis. Subcutaneous injection of unfractionated heparin was started for venous thromboembolism prophylaxis, and he is monitored closely with serial abdominal examinations. On hospital day five, he noted acute onset of left lower extremity pain and is found to have absent pedal pulses in the affected limb. His platelet count is noted to have dropped from 250 000/mm 3 to 90 000/mm 3 , and his creatinine has increased from 1.2 mg/dL to 2.8 mg/dL. He is taken to the operating room where he underwent thrombectomy of a white appearing