1.
Survival of trauma patients after massive red blood cell transfusion using a high or low red blood cell to plasma transfusion ratio
Rajasekhar A, Gowing R, Zarychanski R, Arnold DM, Lim W, Crowther MA, Lottenberg R
Critical Care Medicine. 2011;39((6):):1507-13.
Abstract
OBJECTIVE Early and aggressive treatment of trauma-associated coagulopathy through transfusion of high plasma to packed red blood cell ratios is gaining favor. Whether this strategy is associated with improved survival is unclear. We performed a systematic review to determine whether higher plasma to packed red blood cell ratios compared with lower plasma to packed red blood cell ratios were associated with a survival advantage. DATA SOURCES We searched electronic databases MEDLINE, Embase, and Web of Science from 1950 to February 2010 for studies comparing mortality in massively transfused trauma cohorts receiving different plasma to packed red blood cell ratios. STUDY SELECTION Two reviewers independently performed study selection. Discrepancies in study selection were resolved by discussion and consensus. DATA EXTRACTION Two reviewers independently extracted data from each study using a standardized form. Two authors independently assessed study quality using the Newcastle-Ottawa Scale. DATA SYNTHESIS Eleven observational studies and no randomized controlled trials were identified. Three studies found a survival benefit with a 1:1 plasma to packed red blood cell transfusion ratio compared with either higher or lower ratios. Six studies did not examine a 1:1 ratio but concluded that higher plasma to packed red blood cell ratios improved survival. Secondary outcomes, including multiorgan system failure, packed red blood cell transfusion, respiratory outcomes, and coagulation variables, did not uniformly fav or 1:1 or higher plasma to packed red blood cell ratios. CONCLUSIONS Methodological flaws, including survival bias, and heterogeneity between studies preclude statistical comparisons concerning the effects of a 1:1 plasma to packed red blood cell transfusion ratio. There is insufficient evidence to support a survival advantage with a 1:1 plasma to packed red blood cell transfusion strategy. Randomized controlled trials evaluating safety and efficacy are warranted before a high plasma to packed red blood cell transfusion ratio can be recommended.
2.
The American Society of Hematology 2011 evidence-based practice guideline for immune thrombocytopenia
Neunert C, Lim W, Crowther M, Cohen A, Solberg JrL, Crowther MA
Blood. 2011;117((16):):4190-4207.
Abstract
Immune thrombocytopenia (ITP) is commonly encountered in clinical practice. In 1996 the American Society of Hematology published a landmark guidance paper designed to assist clinicians in the management of this disorder. Since 1996 there have been numerous advances in the management of both adult and pediatric ITP. These changes mandated an update in the guidelines. This guideline uses a rigorous, evidence-based approach to the location, interpretation, and presentation of the available evidence. We have endeavored to identify, abstract, and present all available methodologically rigorous data informing the treatment of ITP. We provide evidence-based treatment recommendations using the GRADE system in those areas in which such evidence exists. We do not provide evidence in those areas in which evidence is lacking, or is of lower quality - interested readers are referred to a number of recent, consensus-based recommendations for expert opinion in these clinical areas. Our review identified the need for additional studies in many key areas of the therapy of ITP such as comparative studies of front-linetherapy for ITP, the management of serious bleeding in patients with ITP, and studies that will provide guidance about which therapy should be used as salvage therapy for patients after failure of a first-line intervention. 2011 by The American Society of Hematology.
3.
The frequency and clinical significance of thrombocytopenia complicating critical illness: a systematic review
Hui PLY, Cook DJ, Lim W, Fraser G, Arnold DM
Blood. 2010;116((21):): Abstract No. 4664.
4.
Use of antifibrinolytic therapy to reduce transfusion in patients undergoing orthopedic surgery: a systematic review of randomized trials
Kagoma YK, Crowther MA, Douketis J, Bhandari M, Eikelboom J, Lim W
Thrombosis Research. 2009;123((5):):687-96.
Abstract
BACKGROUND Minimizing bleeding and transfusion is desirable given its cost, complexity and potential for adverse events. Concerns have been heightened by recent data demonstrating that bleeding events may predict worse outcomes and by warnings about the safety of erythropoietic stimulating agents. Prior small studies suggest that antifibrinolytic agents may reduce bleeding and transfusion need in patients undergoing total hip replacement (THR) or total knee arthroplasty (TKA). However, no single study has been large enough to definitively determine if these agents are safe and effective. To address this issue we performed a systematic review of randomized trials describing the use of tranexamic acid, epsilon aminocaproic acid, or aprotinin administration in the perioperative setting. METHODS MEDLINE, EMBASE, CINAHL and the Cochrane databases were searched for relevant trials. Two independent reviewers abstracted total blood loss, transfusion requirements, and venous thromboembolism (VTE) rates. Data were combined using the Mantel-Haenszel method and dichotomous data expressed as relative risk (RR) with 95% confidence intervals (CI). RESULTS Patients receiving antifibrinolytic agents had reduced transfusion need (RR 0.52; 95% CI, 0.42 to 0.64; P<0.00001), reduced blood loss and no increase in the risk of VTE (RR 0.95% CI, 0.80 to 1.10, I(2)=0%, P=0.531). CONCLUSIONS We conclude that antifibrinolytic agents may reduce bleeding and transfusion in patients undergoing THR or TKA who receive appropriate antithrombotic prophylaxis. There is a need for a large, adequately powered prospective study to carefully examine the safety and efficacy of these agents.
5.
Avoiding transfusions in children undergoing cardiac surgery: a meta-analysis of randomized trials of aprotinin
Arnold DM, Fergusson DA, Chan AK, Cook RJ, Fraser GA, Lim W, Blajchman MA, Cook DJ
Anesthesia and Analgesia. 2006;102((3):):731-737.