boelastography (TEG). Using an electronic transducer and a filament suspended in a whole blood sample, TEG mea- sures initiation of coagulation, propagation kinetics, fibrin- platelet interaction, clot strength, and fibrinolysis indepen- dent of sample temperature (7). This provides better identification of the deficient component of the coagula- tion cascade, potentially permitting more targeted ther- apy for coagulopathy reversal (8). In a prospective ani- mal study using TEG, Martini et al. demonstrated that “hypothermia inhibited clotting times and clotting rates, whereas hemorrhage impaired clot strength. The combi- nation of hypothermia with hemorrhage impaired all these clotting parameters” (6). Similar results have been reported in human studies (9). Further, TEG results are available to the emergency physician in a little over 30 min. This combination of accuracy and speed potentially makes TEG the ideal ED bedside test for trauma-associated coagulopathy. However, studies utilizing TEG to devise blood component-specific and goal-directed coagulopa- thy reversal are still needed (10). Obviously, we want to provide the best outcomes for the most patients. We should consider the potential harm from overuse of blood component therapy. U.S. Navy investigators have reported that in-theater blood transfu- sion is independently associated with infection and re- source over-utilization (11). In addition to the acute adverse effects of transfusion listed by Dr. Fraga, long- term effects such as transfusion-associated microchimer- ism and potentially increased autoimmune disease risk have been identified in military populations after trans- fusion (12,13). We should strive to, first, do no harm and second, maximize the benefit for all our patients when resources are scarce. As in previous wars, the medical insights gained from Operations Iraqi Freedom and Enduring Freedom will go on to benefit generations of trauma patients. However, the dust has not settled regarding the potential benefits of current in-theater transfusion recommendations. We urge all emergency physicians to enter into a discussion with their surgical colleagues before implementing any mili- tarily derived transfusion practices. John Joseph Devlin, MD Miguel A Gutierrez, MD Department of Emergency Medicine Naval Medical Canter Portsmouth Portsmouth, Virginia doi:10.1016/j.jemermed.2009.08.069 REFERENCES 1. Fraga GP, Bansai V, Coimbra R. Transfusion of blood products in trauma: an update. J Emerg Med 2010;39:253– 60. 2. Sperry JL, Ochoa JB, Gunn SR, et al. An FFP:PRBC transfusion ratio  1:1.5 is associated with a lower risk of mortality after massive transfusion. J Trauma 2008;65:986 –93. 3. Scalea TM, Bochicchio KM, Lumpkins K, et al. Early aggressive use of fresh frozen plasma does not improve outcome in critically injured trauma patients. Ann Surg 2008;248:578 – 84. 4. Snyder CW, Weinberg JA, McGwin G, et al. The relationship of blood product to mortality: survival benefit or survival bias? J Trauma 2009;66:358 – 63. 5. Hess JR, Dutton RB, Holcomb JB, Scalea TM Giving plasma at a 1:1 ratio with red cells in resuscitation: who might benefit? Trans- fusion 2008;48:1763–5. 6. Martini WZ, Cortez DS, Dubick MA, Park MS, Holcomb JB. Thrombelastography is better than PT, aPTT, and activated clotting time in detecting clinically relevant clotting abnormalities after hypothermia, hemorrhagic shock and resuscitation in pigs. J Trauma 2008;65:535– 43. 7. Rugeri L, Levrat A, David JS, et al. Diagnosis of early coagulation abnormalities in trauma patients by rotation thrombelastography. J Thromb Haemost 2007;5:289 –95. 8. Jeger V, Zimmerman H, Exadaktylos AK. Can RapidTEG accel- erate the search for coagulapathies in the patient with multiple injuries? J Trauma 2009;66:1253–7. 9. Dirkmann D, Hanke AA, Görlinger K, Peters J. Hypothermia and acidosis synergistically impair coagulation in human whole blood. Anesth Analg 2008;106:1627–32. 10. Wade CE, Dubick MA, Blackbourne LH, Holcomb JB. It is time to assess the utility of thromboelastography in the administration of blood products to the patient with traumatic injuries. J Trauma 2009;66:1258. 11. Dunne JR, Riddle MS, Danko J, Hayden R, Petersen K. Blood transfusion is associated with infection and increased resource utilization in combat casualties. Am Surg 2006;72:619 –26. 12. Dunne JR, Lee TH, Burns C, Cardo LJ, Curry K, Busch MP. Transfusion-associated microchimerism in combat casualties. J Trauma 2008;64(2 Suppl):S92– 8. 13. Utter GH, Lee TH, Rivers RM, et al. Microchimerism decades after transfusion among combat-injured US veterans from the Vietnam, Korean, and World War II conflicts. Transfusion 2008; 48:1609 –15. e RESPONSE e To the Editor: We would like to thank Drs. Devlin and Gutierrez for their interest in our review article regarding massive blood transfusion in trauma (1). The authors pointed out that a number of scientific articles were not available at the time of our submission. We appreciate the opportu- nity to comment on important data recently published. The transfusion strategy for the severely hemorrhag- ing trauma patient cannot be universal. In this regard, trauma surgeons and emergency physicians must be able to differentiate between “hemorrhage requiring massive transfusion” and “hemorrhage that will likely need trans- fusion.” These scenarios have different physiologic con- sequences, in particular with regard to the patient’s co- agulation profile. Unfortunately, studies that seem to challenge the benefit of a high packed red blood cells (PRBCs):fresh frozen plasma (FFP) ratio may not be The Journal of Emergency Medicine 343