the data presented by schochl and colleagues will be seen as intriguing , important , innovative , and controversial . this paper builds on work by dr detmer fries , published in a swine injury model in 2006 . however , as with all retrospective studies , caution must be exercised before widespread adoption . the usual concerns apply as there is no control group , the data supporting the thromboelastometry goal - directed algorithm are not presented , and the risks of using and combining fibrinogen concentrates and plasma complex concentrates ( pccs ) in trauma patients are unknown . preclinical and clinical evidence to answer these questions is lacking and should be investigated . with regards to the study by schochl and colleagues , i am concerned with the comparison of mortality rates in the small numbers of seriously injured patients collected over 5 years to that predicted by the trauma injury severity score ( triss ) and by the revised injury severity classification ( risc ) score . it is very easy for such small data sets to suffer significant statistical problems when attempting to match injuries and initial physiology . several questions are apparent : when the thromboelastometry was repeated , did the test results change ( improve ? ) after transfusion of the proscribed agent ? what was the timing of the fibrinogen and pcc concentrates in relation to red blood cells ( rbcs ) ? how did mortality change over time , as the authors became more comfortable with their alternative resuscitation strategy ? despite these and many more questions , i sincerely congratulate the authors on forging ahead and introducing a novel resuscitation approach . the issues inherent in this retrospective study ( and in every one of the recently published retrospective transfusion studies , including ours ) are significant and will only be resolved when prospective studies are finally performed . as an aside , this standard comment leads me to wonder why we must have level i data to change traditional practice , when the current transfusion traditions are based on small , uncontrolled , rarely read , retrospective studies utilizing blood products no longer available . tradition is recognized as the hardest thing to change , and the recent and now numerous transfusion studies in seriously injured patients are arguably leading the way in a wholesale revolution in transfusion medicine . it seems that physiology is starting to take precedence over tradition in this area , and other specialties are taking notice . we now recognize that fully one - third of transfused patients are coagulopathic . for years , in seriously injured trauma patients suffering hemorrhagic shock , we first gave multiple varieties of salt solutions , followed by rbcs . there was an ongoing controversy about crystalloid versus colloid ; these resuscitation fluids increase coagulation problems and neither increase oxygen delivery . only after liters of these fluids were transfused were components that both increased intravascular volume and helped reverse coagulopathy finally delivered . now , many centers are giving early and increased amounts of plasma proteins and platelets . at our center we more frequently give plasma before rbcs in our seriously injured trauma patients that suffer hemorrhagic shock . anecdotally , this change in practice has been associated with less bleeding , improved survival , decreased edema and lowered multiple organ failure rates . we feel that many of these products not only replace coagulation factors , facilitating early cessation of bleeding , and provide effective volume resuscitation , but more importantly stabilize the endothelium , reverse the early coagulopathy of trauma , reverse endothelial permeability , decrease edema and repair the endothelium , thus preventing early onset of multiple organ failure related to resuscitation injury . the thousands of proteins present in platelets and plasma certainly ' do more than ' just replace the few coagulation proteins we commonly measure . the transfusion method of schochl and colleagues appears to be more physiologic and data driven when compared to the tradition - motivated approach to resuscitation of the severely injured trauma patient in hemorrhagic shock . more studies like this will soon see the light of publication and form the basis for a revolution in transfusion therapy over the next decade . i think that commercial entities should take note , as their approach will certainly open new markets and opportunities . current blood banks are largely focused on logistical issues of shelf life , avoiding disease transmission , and the immunologic consequences of liquid transfusion . however , there have been very few well designed studies over the past 30 years in the transfusion literature describing any clinical improvements after transfusion in trauma patients . amazingly , there is no requirement to have clinical outcome data when modifications to currently approved blood products are introduced . injury has been recognized as causing more than 5 million deaths worldwide and is listed as a major global issue by the who . it is easy to anticipate a separation of emergency transfusion in rapidly bleeding patients from the traditional blood bank over the next decade , with dried blood products / proteins utilized in a point of care mode , stored in the clinical areas where the patients are cared for ( including the pre - hospital environment ) , and resuscitation based upon laboratory data available within minutes that guide protein - specific infusion . it will be nice to only transfuse what is needed , based on level i data , finally balancing risk and benefit in a data - driven fashion for the benefit of our patients .
schochl and co - authors have described a 5-year retrospective study that outlines a novel , important and controversial transfusion concept in seriously injured trauma patients . 
 traditionally , clinicians have been taught to use a serial approach , resuscitating hypovolemic trauma patients with a form of crystalloid or colloid , followed by red blood cells ( rbcs ) , then fresh frozen plasma ( ffp ) , and lastly platelets . 
 the data supporting this widely accepted approach are remarkably weak . 
 conversely , schochl and colleagues , in an innovative , retrospective study , describe the use of fibrinogen concentrate , plasma complex concentrate , rbcs , ffp , and platelets driven by a thromboelastometry - based algorithm . 
 finally , it appears that transfusion therapy is becoming driven by physiology .