1.
A cluster-randomized controlled trial of a blood conservation algorithm in patients undergoing total hip joint arthroplasty
Wong CJ, Vandervoort MK, Vandervoort SL, Donner A, Zou G, MacDonald JK, Freedman J, Karkouti K, MacDonald SJ, Feagan BG
Transfusion. 2007;47((5):):832-41.
Abstract
BACKGROUND The optimum strategy for reducing allogeneic blood transfusion in patients undergoing total hip joint arthroplasty (THJA) is unknown. STUDY DESIGN AND METHODS The effectiveness of a comprehensive blood conservation algorithm (BCA) was evaluated by means of a cluster randomization trial. Thirty hospitals performing primary THJA were randomly assigned to implement the algorithm or to continue with usual care (UC). Subsequently, the institutional rate of allogeneic transfusion was determined for 60 consecutive patients who underwent surgery at each site. The BCA consisted of patient and provider education, hemoglobin-based recommendations for specific blood conservation strategies (recombinant human erythropoietin [rHuEPO] or autologous blood donation [ABD]) and transfusion guidelines. The main outcome measure was the institutional allogeneic transfusion rate. RESULTS One hospital withdrew consent after randomization, resulting in 14 hospitals assigned to BCA and 15 to UC. In the BCA arm, the institutional rates of rHuEPO use and ABD participation were 20. 1 and 27. 1 percent compared to 0. 6 and 25. 8 percent, respectively, in the UC arm. The allogeneic transfusion rate was substantially reduced in hospitals assigned to the BCA group (p = 0. 02; absolute risk reduction, 9. 6% [26. 1% UC vs. 16. 5% BCA]). Multivariate analysis of patient-level data showed that assignment to the UC arm was an independent risk factor for allogeneic transfusion (p = 0. 037; odds ratio, 1. 8; 95% confidence interval, 1. 0-3. 1) when adjusted for other prognostic factors. No differences were observed in the use of autologous blood. CONCLUSION A comprehensive approach to blood conservation was superior to UC for reducing allogeneic transfusion in patients undergoing THJA.
2.
A program to reduce allogeneic blood exposure in patients undergoing HIP arthroplasty: a cluster randomized trial
Wong C, Vandervoort M, Vandervoort S, Donner A, Zou G, Macdonald J, Freedman J, Karkouti K, Macdonald S, Feagan B
Vox Sanguinis. 2005;89((Suppl 1):):119. Abstract No. T-PA-070.
3.
Anti-D (WinRho SD) treatment of children with chronic autoimmune thrombocytopenic purpura stimulates transient cytokine/chemokine production
Semple JW, Allen D, Rutherford M, Woloski M, David M, Wakefield C, Butchart S, Freedman J, Blanchette V, Canadian Children's Platelet Study Group
American Journal of Hematology. 2002;69((3):):225-7.
Abstract
Intravenous anti-D is often used in the treatment of autoimmune thrombocytopenic purpura (AITP), but little is known about its mechanisms of action. To investigate anti-D's potential in vivo mechanism(s) of action, a small group (N = 7) of children with chronic AITP was studied. The children initially received either 25 or 50 microg/kg of WinRho-SD in a four-cycle cross-over trial, and peripheral blood samples from the first and third cycles were assessed for cytokine levels at pre-treatment, 3 hr, 1 day, and 8 days post-treatment. Results showed that platelet counts significantly increased in all the children by day 8 post-treatment. Analysis of serum by ELISA showed that there was a significant but transient rise in both pro- and anti-inflammatory cytokine/chemokine levels (e.g., IL1RA, IL6, GM-CSF, MCP-1 alpha, TNF-alpha and MCP-1) by 3 hr post-treatment in both cycles which returned to baseline levels by 8 days post-treatment. These results suggest that anti-D administration may initially activate the RES in the form of cytokine/chemokine secretion, which is subsequently followed by an increase in platelet counts. It is possible that the induced cytokine/chemokine storm may have an effect on several physiological processes such as those mediating either adverse effects or potentially RES phagocytic activity.
4.
Pentastarch instead of albumin as replacement fluid for therapeutic plasma exchange. The Canadian Apheresis Group
Rock G, Sutton DM, Freedman J, Nair RC
Journal of Clinical Apheresis. 1997;12((4):):165-9.
Abstract
BACKGROUND Human albumin is commonly used as a replacement fluid in therapeutic plasma exchange (PE). In order to determine whether Pentaspan (PES), a synthetic low molecular weight starch solution, might be an effective substitute, we compared albumin with PES in 12 patients with myasthenia gravis or Guillain-Barre syndrome. STUDY DESIGN AND METHODS Six patients were randomly assigned to receive PES and six to receive albumin as replacement fluid during their course of PE, which consisted of two to five treatments delivered over a maximum of 10 days. All patients were hospitalized and observed closely. Blood pressures were recorded every 4 hours and daily measurements were made of hematologic, coagulation, and immunoglobulin parameters. RESULTS Individual exchange volumes were similar in each group (37 ml/kg--range 6-62--in patients receiving albumin vs. 41 ml/kg--range 6-41--in those receiving PES). Changes in immunoglobulin levels and coagulation parameters were similar but mild, transient thrombocytopenia was observed in three subjects given PES. Total serum protein and albumin levels decreased significantly in patients replaced with PES. Clinically, PES was well tolerated. Hypotension occurred in one patient who developed septic shock due to an infected femoral catheter; in another patient, a pre-existing pleural effusion was thought to increase slightly. CONCLUSIONS PES appears to be a safe replacement fluid for PE, but larger clinical studies are required to confirm these findings.
5.
Extreme leukodepletion as an intervention to prevent platelet alloimmunization in new leukemics: results of a randomized study
Blanchette V, Freedman J, Adams M, MacMillan J, Wang E
Blood. 1991;78:476a.. Abstract No. 1894.