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Surgical Critical Care and Emergency Surgery


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resuscitation: report of the panel. J Trauma Acute Care Surg , 78 (6), 1220–1229.Gonzalez, E., Pieracci, F.M., Moore, E.E., et al. (2010) Coagulation abnormalities in the trauma patient: The role of point‐of‐care thromboelastography. Semin Thromb Hemost , 36 (7), 723–737.

      7 Which of the following is not an advantage of rapid thrombelastography (TEG) in the setting of trauma?Viscoelastic assays better characterize trauma‐induced coagulopathy when compared to conventional coagulation profiles.TEG can better direct massive transfusion than protocol‐driven balanced ratio component therapy allowing for reduced product administration.TEG is the only clinically available means of detecting fibrinolysis accurately and in a point‐of‐care setting.TEG results are available within minutes.TEG has demonstrated survival benefit in guiding the management of thromboembolic events in the setting of post‐injury hypercoagulability.TEG characterizes the life‐span of a clot; from initial fibrin formation, to incorporation of platelets, to fibrinolysis. With results available within 10 minutes, an initial hemostatic assessment with TEG identifies patients at risk for post‐injury coagulopathy upon arrival. The point‐of‐care variables that result enable the clinician direct management of patients in the trauma bay in real time while allowing for a data‐driven, goal‐directed hemostatic resuscitation. A recent clinical trial demonstrated that the use of TEG to guide massive transfusion in trauma patients, compared with conventional coagulation assays, resulted in a decrease in mortality while using fewer blood products. TEG is also currently used for patient‐personalized administration of antifibrinolytics (e.g., tranexamic acid) based on LY30 parameters rather than administering TXA empirically when massive transfusion is required. Additionally, because TEG characterizes dynamic hypercoagulability and simultaneously reflects the antithrombotic effect of chemoprophylaxis, it may serve as a template for designing tailored thromboprophylaxis regimens; however additional studies are needed, and survival benefit has yet to be demonstrated.Answer: EGonzalez, E., Moore, E.E., Moore, H.B., et al. (2016) Goal‐directed hemostatic resuscitation of trauma‐induced coagulopathy: A pragmatic randomized clinical trial comparing a viscoelastic assay to conventional coagulation assays. Ann Surg , 263 (6), 1051–1059.Gonzalez, E., Pieracci, F.M., Moore, E.E., et al. (2010) Coagulation abnormalities in the trauma patient: The role of point‐of‐care thromboelastography. Semin Thromb Hemost , 36 (7), 723–737.

      8 A 29‐year‐old man dropped off by his friend after crashing his all‐terrain vehicle. Upon evaluation, he has altered mental status and a distended abdomen that is diffusely tender. His blood pressure is 80/60 mmHg and heart rate 140 per minute. He does not respond to initial resuscitation and massive transfusion protocol is activated. The time of his injury is unclear at this time and his initial thromboelastography (TEG) results reveal normal R time, normal k time, normal MA and LY30 greater than normal. What is the next best step in management?Give 2 units of fresh frozen plasmaAdminister 1 g of tranexamic acid (TXA)Give 1 unit of plateletsGive 10 units of cryoprecipitateGive cryoprecipitate and plateletsTEG is useful in evaluating trauma‐induced coagulopathy for goal‐directed therapy. In this instance, the patient has massive transfusion requirements and time of injury is unclear. Rather, than empirically administering TXA, the TEG is useful in quickly identifying that this patient would likely benefit from its administration. LY30 greater than 3–5% is representative of hyperfibrinolysis. It seems intuitive that an antifibrinolytic medication should only be administered to those who have demonstrable hyperfibrinolysis; however, advocates for its empiric administration to all trauma patients exist. As evident by the CRASH‐II trial, mortality benefit was seen in all trauma patients receiving TXA; however, this study also found that administration of tranexamic acid greater than 3 hours after injury was associated with increased mortality. Therefore, it is prudent to utilize TEG to ascertain those patients most likely to benefit from TXA.Answer: BGonzalez, E., Moore, E.E., and Moore, H.B. (2017) Management of trauma‐induced coagulopathy with thrombelastography. Crit Care Clin , 33 (1), 119–134.

      9 A 35‐year‐old man is recovering in the intensive care unit 1 day after undergoing a damage control laparotomy for hemodynamic instability following a motorcycle crash in which he suffered a severe left pulmonary contusion, pneumothorax, femur fracture, grade 5 splenic laceration requiring splenectomy and destructive colon injury. He required massive transfusion as part of his resuscitation. Currently, his blood pressure is 110/75 mm Hg and heart rate 100. He is awake and breathing spontaneously on the ventilator with minimal support. His laboratory results reveal a hemoglobin of 7.9 g/dL, platelets 40 000/mm 3 , prothrombin time 16 seconds, partial thromboplastin time 38 seconds, and fibrinogen 255 g/dL. He has remained stable and off vasopressors since admission to the ICU.Which product(s) should be transfused at this time?Red blood cells, platelets, and plasmaRed blood cells, platelets, and cryoprecipitateTranexamic AcidNo products at this timeRed blood cellsBased on guidelines for enrollment in the current Pragmatic, Randomized Optimal Platelets and Plasma Ratios (PROPPR) study, criteria for stopping the massive transfusion protocol should include both anatomic (control of bleeding) and physiologic criteria (normalizing hemodynamic status). In this stable trauma patient without evidence of active bleeding, no blood products are needed at this time. A restrictive transfusion strategy maintaining hemoglobin at 7.0–9.0 g/dL has been shown to be as effective as a liberal transfusion strategy maintaining hemoglobin concentration at 10.0–12.0 g/dL. For those with an APACHE II score ≤ 20, 30‐day mortality is significantly less with a restrictive strategy. In the absence of clinical bleeding, fresh frozen plasma transfusion may be associated with an increased incidence of acute lung injury. Evidence to support prophylactic platelet transfusion in critically ill patients without active bleeding is conflicting. Several authors have recommended avoidance 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