Cryopreserved red blood cells are superior to standard liquid red blood cells.

BACKGROUND: Liquid preserved packed red blood cell (LPRBC) transfusions are used to treat anemia and increase end-organ perfusion. Throughout their storage duration, LPRBCs undergo biochemical and structural changes collectively known as the storage lesion. These changes adversely affect perfusion and oxygen off-loading. Cryopreserved RBCs (CPRBC) can be stored for up to 10 years and potentially minimize the associated storage lesion. We hypothesized that CPRBCs maintain a superior biochemical profile compared with LPRBCs. METHODS: This was a prospective, randomized, double-blinded study. Adult trauma patients with an Injury Severity Score (ISS) greater than 4 and an anticipated 1-U to 2-U transfusion of PRBCs were eligible. Enrolled patients were randomized to receive either CPRBCs or LPRBCs. Serum proteins (haptoglobin, serum amyloid P, and C-reactive protein), proinflammatory and anti-inflammatory cytokines, d-dimer, nitric oxide, and 2,3-DPG concentrations were analyzed. Mann-Whitney U-test and Wilcoxon rank sum test were used to assess significance (p < 0.05). RESULTS: Fifty-seven patients were enrolled (CPRBC, n = 22; LPRBC, n = 35). The LPRBC group's final interleukin 8, tumor necrosis factor α, and d-dimer concentrations were elevated compared with their pretransfusion values (p < 0.05). After the second transfused units, 2,3-DPG was higher in the patients receiving CPRBCs (p < 0.05); this difference persisted throughout the study. Finally, serum protein concentrations were decreased in the transfused CPRBC units compared with LPRBC (p < 0.01). CONCLUSION: CPRBC transfusions have a superior biochemical profile: an absent inflammatory response, attenuated fibrinolytic state, and increased 2,3-DPG. A blood banking system using both storage techniques will offer the highest-quality products to critically injured patients virtually independent of periodic changes in donor availability and transfusion needs. LEVEL OF EVIDENCE: Therapeutic study, level II.

The International Normalized Ratio overestimates coagulopathy in stable trauma and surgical patients.

BACKGROUND: The international normalized ratio (INR) was developed to assess adequacy of Coumadin dosing. Its use has been generalized to guide fresh frozen plasma (FFP) therapy in stable patients. Thrombelastography (TEG) is a whole-blood assay measuring the viscoelastic properties of the clot in near real time. This study hypothesized that INR does not reflect coagulopathy and should not be used to guide FFP therapy in stable trauma and surgical patients. METHODS: Prospective observational data were collected from stable trauma and surgical patients (n = 106) who received FFP transfusions. Pretransfusion and posttransfusion blood samples were obtained to assess complete blood count, standard coagulation parameters (INR, partial thromboplastin time, fibrinogen and D-dimer), soluble clotting factors (II, V, VII, VIII, IX, X, XI, XII, proteins C and S) and TEG. Data were analyzed using a Mann-Whitney U-test. Significance was defined as p < 0.05. RESULTS: A total of 262 U of FFP were transfused, with 78% of 106 patients receiving two or more units. Despite a reduction in INR, median TEG values remained within normal limits, while clotting factor levels retained adequate function to produce normal clotting before and following FFP transfusion. CONCLUSION: The use of FFP in this population did not affect coagulation status in a clinically relevant manner based on TEG values and coagulation factor function. INR is not a predictor of coagulopathy and should not be used to guide coagulation factor replacement in stable trauma and surgical patients. LEVEL OF EVIDENCE: Diagnostic study, level III.

Prehospital intravenous fluid is associated with increased survival in trauma patients.

BACKGROUND: Delivery of intravenous crystalloid fluids (IVF) remains a tradition-based priority during prehospital resuscitation of trauma patients. Hypotensive and targeted resuscitation algorithms have been shown to improve patient outcomes. We hypothesized that receiving any prehospital IVF is associated with increased survival in trauma patients compared with receiving no prehospital IVF. METHODS: Prospective data from 10 Level 1 trauma centers were collected. Patient demographics, prehospital IVF volume, prehospital and emergency department vital signs, lifesaving interventions, laboratory values, outcomes, and complications were collected and analyzed. Patients who did or did not receive prehospital IVF were compared. Tests for nonparametric data were used to assess significant differences between groups (p ≤ 0.05). Cox regression analyses were performed to determine the independent influence of IVF on outcome and complications. RESULTS: The study population consisted of 1,245 trauma patients; 45 were excluded owing to incomplete data; 84% (n = 1,009) received prehospital IVF, and 16% (n = 191) did not. There was no difference between the groups with respect to sex, age, and Injury Severity Score (ISS). The on-scene systolic blood pressure was lower in the IVF group (110 mm Hg vs. 100 mm Hg, p < 0.04) and did not change significantly after IVF, measured at emergency department admission (110 mm Hg vs. 105 mm Hg, p = 0.05). Hematocrit/hemoglobin, fibrinogen, and platelets were lower (p < 0.05), and prothrombin time/international normalized ratio and partial thromboplastin time were higher (p < 0.001) in the IVF group. The IVF group received a median fluid volume of 700 mL (interquartile range, 300-1,300). The Cox regression revealed that prehospital fluid administration was associated with increased survival (hazard ratio, 0.84; 95% confidence interval, 0.72-0.98; p = 0.03). Site differences in ISS and fluid volumes were demonstrated (p < 0.001). CONCLUSION: Prehospital IVF volumes commonly used by PRospective Observational Multicenter Massive Transfusion Study (PROMMTT) investigators do not result in increased systolic blood pressure but are associated with decreased in-hospital mortality in trauma patients compared with patients who did not receive prehospital IVF.

Management of the open abdomen during the global war on terror.

OBJECTIVE: To evaluate factors that are predictive of delayed abdominal closure in patients injured during military conflict. DESIGN, SETTING, AND PATIENTS: Seventy-one patients managed with an open abdomen were identified from records at Landstuhl Regional Medical Center from 2005 and 2006. Follow-up data were available from Walter Reed Army Medical Center. Records were reviewed through all echelons of care. Ordinal logistic regression was used to predict delayed abdominal closure. RESULTS: Patients sustained injury from blunt (n = 2), penetrating (n = 30), and blast (n = 39) mechanisms. The median Injury Severity Score was 25 (interquartile range, 17-34). Abdominal injury was observed in 85% of patients, and 48% underwent a massive transfusion. The median time to transfer to the United States was 5.3 days (interquartile range, 4.3-6.8 days). Abdomens were definitively closed downrange (11%), at Landstuhl Regional Medical Center (33%), or at Walter Reed Army Medical Center (56%). The median time until abdominal closure was 13 days (interquartile range, 4-40 days) in 2005 compared with 4 days (interquartile range, 1-14.5 days) in 2006 (P = .02). The multivariate model identified massive transfusion (odds ratio, 3.9), presence of complications (odds ratio, 5.1), and an injury date in 2005 (odds ratio, 3.4) as independently predictive variables for later abdominal closure. CONCLUSIONS: Massive transfusion, occurrence of complications, and earlier injury date were predictive of delayed abdominal closure in casualties managed with an open abdomen. These data suggest an evolving approach to the management of severely injured combat casualties that involves earlier abdominal closure.