Red Cell Transfusions In Patients Research Articles

The Need for Red Cell Support During Non-Cardiac Surgery Is Associated to Pre-Transfusion Levels of FXIII and the Platelet Count.

Unexpected intraoperative bleeding is associated with a reduced availability of crosslinking capacity (provided through factor XIII (FXIII)) per unit of generated thrombin. Furthermore, FXIII deficiency and thrombocytopenia (but not fibrinogen deficiency) are the most prevalent modulators of clot firmness in the immediate postoperative setting. In this study, we therefore evaluated whether levels of FXIII, fibrinogen, or the platelet count influenced the probability of intraoperative red cell transfusions in patients in the operating theatre. This retrospective study was comprised of 1023 patients, which were in need of blood product support in the operating theatre and of which 443 received red cell transfusions. Due to standard operating procedures, FXIII activity, fibrinogen concentration, and platelet count were measured before transfusion took place, but without influencing the decision to transfuse. FXIII deficiency was frequent (50%), as was thrombocytopenia (49%), but not fibrinogen deficiency (9%). FXIII deficiency was associated with a significantly increased probability to receive red cell transfusions (OR 4.58, 95% CI 3.46–6.05) as was thrombocytopenia (OR 1.94, 95% CI 1.47–2.56), but not fibrinogen deficiency (OR 1.09, 95% CI 0.67–1.76). Similar results were seen for cut-off independent evaluations (receiver operating characteristics (ROC) curves, using continuously distributed variables), where the areas under the curves (AUC) of red cell transfusion for FXIII activity was 0.744 (95% CI 0.716–0.770)/0.632 (95% CI 0.601–0.661) for the platelet count, and 0.578 (95% CI 0.547–0.609) for fibrinogen concentration. All AUCs were significantly different from each other (p < 0.0001 and p = 0.0106, respectively), indicating that FXIII activity was a significantly better predictor of red blood cell (RBC) transfusion than platelet count and fibrinogen concentration. These results suggest that pre-transfusion FXIII activity and to a lesser extent the platelet count influence the probability of intraoperative red cell transfusions. Modifying FXIII activity and/or the platelet count might influence the need for downstream red cell transfusion, thus potentially reducing transfusion associated morbidity. This, however, needs confirmation in future studies.

Quality of Evidence-Based Guidelines for Transfusion of Red Blood Cells and Plasma: A Systematic Review.

Many transfusion guidelines are available, but little appraisal of their quality has been undertaken. The quality of guidelines may potentially influence adoption. Our aim was to determine the quality of evidence-based transfusion guidelines (EBG) for red cells and plasma, using the Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument, and assess duplication and consistency of recommendations. MEDLINE and EMBASE were systematically searched for EBG from 2005 to June 3, 2016. Citations were reviewed for inclusion in duplicate. A guideline was included if it had a specified clinical question, described a systematic search strategy, included critical appraisal of the literature and a description of how recommendations were developed. Four to six physicians used AGREE II to appraise each guideline. Median and scaled scores were calculated, with each item scored on a scale of one to seven, seven representing the highest score. Of 6174 citations, 30 guidelines met inclusion criteria. Twenty six guidelines had recommendations for red cells and 18 included recommendations for plasma use. The median score, the scaled score and the interquartile range of the scaled score were: scope and purpose: median score 5, scaled score 60%, IQR (49-74%); stakeholder involvement 4, 43%, (33-49%); rigor of development 4, 41%, (19-59%); clarity of presentation 5, 69%, (52-81%); applicability 1, 16%, (9-23%); editorial independence 3, 43%, (20-58%). Sixteen guidelines were evaluated to have a scaled domain score of 50% or less. Variations in recommendations were found for the use of hemoglobin triggers for red cell transfusion in patients with acute coronary syndromes and for plasma use for patients with bleeding. Our findings document, limited rigor in guideline development and duplication and inconsistencies in recommendations for the same topic. The process of developing guidelines for red cells and plasma transfusion can be enhanced to improve implementation.

How I manage red cell transfusions in patients with sickle cell disease.

Sickle cell disease is one of the commonest serious inherited diseases in the world, and red cell transfusion is still one of the few effective treatments for acute and chronic complications. Transfusion corrects anaemia and dilutes out the number of red cells able to cause vaso-occlusion and vascular damage. Urgent red cell transfusions are used to correct acute anaemia, treat acute chest syndrome and patients with acute neurological symptoms. We use elective transfusions preoperatively for moderate risk surgery, and in some pregnant women. There is good evidence for the use of long-term regular transfusions in primary stroke prevention, with the aim of keeping the percentage of sickle haemoglobin below 30%. Long-term transfusions are also used in secondary stroke prevention, and the management of progressive organ damage, including renal impairment and pulmonary hypertension. Blood needs to be matched for ABO, RH and Kell, although alloantibodies may still develop and require more careful, extended cross-matching. Delayed haemolytic transfusion reactions are relatively common, difficult to diagnose and manage, and potentially fatal.

Late-Breaking Science Abstracts From the American Heart Association's Scientific Sessions 2017 and Late-Breaking Abstracts in Resuscitation Science From the Resuscitation Science Symposium 2017.

### CABG and EP Peri-procedural Dilemmas #### 21574 #### TRiCS III - An International Multicenter Randomized Trial of Transfusion Requirements in Cardiac Surgery C. David Mazer1, Richard P Whitlock2, Dean A Fergusson3, Kevin E Thorpe4, Nadine Shehata5, TRICS III Investigators, Perioperative Anesthesia Clinical Trials Network; 1Anesthesia, St Michaels Hosp, Univ of Toronto, Toronto, Canada, 2Div of Cardiac Surgery and Dept of of Clinical Epidemiology and Biostatistics, Population Health Rsch Institute, McMaster Univ, Hamilton, Canada, 3Depts of Medicine, Surgery, & the Sch of Epidemiology, Public Health and Preventive Medicine, Ottawa Hosp Rsch Institute, Univ of Ottawa, Ottawa, Canada, 4Biostatistics, Applied Health Rsch Cntr and Dalla Lana Sch of Public Health, St. Michael’s Hosp, Univ of Toronto, Toronto, Canada, 5Depts of Medicine, Institute of Health Policy Management and Evaluation, Mount Sinai Hosp, Univ of Toronto, Toronto, Canada. Introduction: There is a critical need to determine the appropriate threshold for red cell transfusion in patients undergoing cardiac surgery since perioperative anemia and allogeneic red blood cell transfusions are both independent predictors of morbidity and mortality. In addition, there is considerable inter-physician and inter-hospital variability in transfusion practice. While restrictive transfusion strategies have been shown to reduce transfusion, their clinical effectiveness and safety in cardiac surgery are not known. Methods: TRICS III is a multicenter randomized controlled trial to evaluate the non-inferiority of a restrictive transfusion strategy compared to a liberal transfusion strategy in cardiac surgery patients with a preoperative European System for Cardiac Operative Risk Evaluation (additive EuroSCORE I) of ≥6 (NCT02042898). Patients were randomized to a “restrictive” strategy (transfusion if hemoglobin <7.5 g/dL intraoperatively and postoperatively) or a “liberal” strategy (transfusion if hemoglobin <9.5 g/dL in the operating room or ICU, and <8.5 g/dL on the ward). The primary outcome is a composite of in hospital death, myocardial infarction, stroke or new renal failure requiring dialysis. Secondary outcomes include duration …

Predictive Factors of Blood Loss and Hospital Stay in Patients With Major Lumbosacral Surgeries: A Multi-Center, Prospective, Cross-Sectional Survey

Background: Blood loss during spinal decompression and fusion is high and at times more than the patient’s total estimated blood. Increased blood loss may increase the risks of morbidity and eventually length of hospital stay (LOS). Objectives: The aim of this study was to identify predictor factors of blood transfusion requirements and the length of hospital stay in adult patients who underwent lumbosacral surgery. Materials and Methods: This was a multicenter cross-sectional study to predict factors of hospital length of stay (LOS) and intraoperative red cell transfusion in patients undergoing major posterior lumbar spinal surgeries. In this study, 298 patients who needed spinal surgery were enrolled. Results: Multiple linear regression results revealed the following information. Among variables that had significant association with the volume of intraoperative blood loss, considerable predictors were the number of level fused (R 2 = 0.42), mean intraoperative SBP (R 2 = 0.22), length of operation (R 2 = 0.31) and increasing age (R 2 = 0.37). Significant predictors for the length of hospital stay were increasing age (R 2 = 0.22), much more comorbid conditions (R 2 = 0.30), operation length (R 2 = 0.27), the number of level fused (R 2 = 0.21) and the volume of intraoperative blood loss (R 2 = O.29). The results of logistic regression revealed that length of operation, preoperative Hb value, number of level fused and mean intraoperative SBP considerably predicted the need for intraoperative blood transfusion. Conclusions: Diminishing intraoperative SBP could decrease intraoperative blood loss and eventually less red cell transfusion and shorter LOS. Besides, correcting preoperative anemia in female patients before elective surgeries could decrease a need for red cell transfusions and ultimately decreased red cell transfusion complication rate and shorter hospital LOS.

The appropriateness of red cell transfusion in patients aged over 65

The appropriateness of red cell transfusion in patients aged over 65

Tranexamic acid for control of blood loss in bilateral total knee replacement in a single stage

Background:Tranexamic acid (TEA) reduces blood loss and red cell transfusions in patients undergoing unilateral total knee arthroplasty (TKA). However, there is not much literature regarding the use of TEA in patients undergoing bilateral TKA in a single stage and the protocols for administration of TEA in such patients are ill-defined.Materials and Methods:We carried out a case control study evaluating the effect of TEA on postoperative hemoglobin (Hb), total drain output, and number of blood units transfused in 52 patients undergoing bilateral TKA in a single stage, and compared it with 56 matched controls who did not receive TEA. Two doses of TEA were administered in doses of 10 mg / kg each (slow intravenous (IV) infusion), with the first dose given just before tourniquet release of the first knee and the second dose three hours after the first one.Results:A statistically significant reduction in the total drain output and requirement of allogenic blood transfusion in cases who received TEA, as compared to the controls was observed. The postoperative Hb and Hb at the time of discharge were found to be lower in the control group, and this result was found to be statistically significant.Conclusion:TEA administered in patients undergoing single stage bilateral TKA helped reduce total blood loss and decreased allogenic blood transfusion requirements. This might be particularly relevant, where facilities such as autologous reinfusion might not be available.

One Intraoperative Dose of Tranexamic Acid for Patients Having Primary Hip or Knee Arthroplasty

Multiple studies suggest tranexamic acid reduces blood loss and red cell transfusions in patients undergoing THA or TKA. However, many of the dosing schedules in these studies are not ideally suited for routine application. We asked whether one 20-mg per kg intraoperative dose of tranexamic acid in patients having primary THA or TKA would (1) decrease perioperative blood loss and red cell transfusion rates and (2) be a cost-effective protocol. We retrospectively reviewed the records of 234 patients operated on from April 1 to June 30, 2007 (before our study protocol) and 259 patients from April 1 to June 30, 2008 with the single-dose protocol. We then compared change in hemoglobin, transfusion rates, hemoglobin at discharge, hospital length of stay, and complications between the two groups. No other routine patient care practices or blood conservation program strategies were altered during this time. We found a reduction in the decrease in hemoglobin in 2008 compared with 2007 for THA and TKA (39 from 46 g/L and 36 from 45 g/L, respectively),which led to a reduction in transfusion rates (3.6% from 13.5% and 2.0% from 13.4%, respectively) and higher hemoglobin levels at discharge [corrected].There were no recorded major adverse events associated with the introduction of this protocol. One 20-mg per kg intraoperative dose of tranexamic acid reduced the perioperative decrease in hemoglobin and red blood cell transfusion rates in patients having TKA and THA compared with those of a similar cohort of patients in whom the protocol was not used. This weight increment dosing facilitated pharmacy drug preparation, led to minimal dose variability and wastage, and resulted in a substantial estimated cost savings. Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Quality of life and use of red cell transfusion in patients with myelodysplastic syndromes. A systematic review

The main treatment for many patients with Myelodysplastic Syndromes (MDS) remains red cell transfusion to attenuate the symptoms of chronic anemia. Fatigue can reduce a patient's health related quality of life (HRQoL), but there is little understanding of the optimal use of transfusions to improve this. A systematic review was performed to identify and appraise publications reporting the use of HRQoL instruments in patients with MDS. A total of 17 separate studies were identified that used 14 HRQoL instruments, but only one MDS disease specific HRQoL instrument (QOL-E) was reported. Two well established HRQoL instruments were most often used in MDS research (variants of the Functional Assessment of Cancer Therapy (FACT) and the European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire (QLQ-C30)). Several common problems were identified in the published literature including a lack of power calculations to detect clinically relevant changes, small sample sizes and significant attrition rates for completion of HRQoL assessments, all of which limit the strength of any conclusions. There is no consensus on the optimal transfusion regimen to improve HRQoL in transfusion-dependent MDS. Future research into HRQoL within MDS is a pressing requirement. Studies should focus on the domains that are of most clinical importance to the patient as well as traditional quantitative changes of hemoglobin concentration.

Change in Liver Iron Concentration (LIC), Serum Ferritin (SF) and Labile Plasma Iron (LPI) Over 1 Year of Deferasirox (DFX/Exjade®) Therapy in a Cohort of Myelodysplastic Patients

Background: Chronic red cell transfusions in patients with MDS result in iron overload, potentially causing hepatic, cardiac and endocrine dysfunction if untreated. DFX, a once-daily, oral iron chelator, has demonstrated dose-dependent reductions in SF and LIC in a variety of iron-overloaded patients. This study, CICL670AUS02, is the first prospective study evaluating the effects of DFX on LIC, SF and LPI in lower-risk patients with MDS.Methods: The study evaluated efficacy and safety of DFX in patients with IPSS Low- and Int-1-risk MDS at three US centers. Initial DFX dose was 20 mg/kg/day with adjustments to 10 or 30 mg/kg/day based on safety and efficacy. LIC was assessed by R2 MRI at baseline (BL), 6 and 12 months (mos). SF, safety analyses and trough LPI levels were also assessed.Baseline characteristics (n=24): Male/female ratio: 16/8; all Caucasian; mean age: 68 years (range 55–81); IPSS Low: 10; Int-1: 14. Time from initial diagnosis: <1 year (n=3; 13%); ≥1–<3 years (n=7; 29%); ≥3 years (n=14; 58%); range (<1–12) years. Mean number of lifetime transfusions was 79 (30–352). Mean (±SEM) SF value was 3848±583 μg/L, mean LIC was 20.64±1.99 mg Fe/g dry weight (dw), and mean LPI was 0.70±0.13 μmol/L; 50% of patients entered the trial with abnormal LPI (>0.5 μmol/L).6-month values: 15/24 patients completed 6 mos. Mean SF (±SEM): 3650±384 μg/L at BL, 3638±870 μg/L at 6 mos (n=13); mean decrease of 12.2 μg/L (P=0.685). Mean LIC (±SEM): 23.10±2.40 mg Fe/g dw at BL, 16.87±1.88 mg Fe/g dw at 6 mos (n=14); mean decrease of 6.2 mg Fe/g dw (P=0.013). Mean LPI (±SEM): 0.82±0.16 μmol/L at BL, 0.12 ± 0.05 μmol/L at 6 mos (n=15); mean decrease of 0.70 μmol/L (P=0.170).12-month values (n=9): Nine patients completed 12 mos of treatment. Mean dose in the nine completers was 20.1 mg/kg/day; three patients increased to 30 mg/kg/day and two decreased to 10 mg/kg/day. Mean SF (±SEM): 4416±1269 μg/L at BL, 2685±316 μg/L at 12 mos; mean decrease of 1730 μg/L (P=0.301; Figure). Mean LIC (±SEM): 23.72±3.82 mg Fe/g dw at BL, 16.79±3.80 mg Fe/g dw at 12 mos; mean decrease of 6.93 mg Fe/g dw (P=0.203). 78% of the nine completers achieved decreases in SF of ≥500 μg/L and >20% from BL. Mean LPI (±SEM; n=8): 0.82±0.19 μmol/L at BL, 0.13±0.10 μmol/L at 12 mos; mean decrease of 0.76 μmol/L (P=0.023)Safety Analysis (n=24): Increases in serum creatinine (SCr) to >33% above BL on ≥2 occasions (highest value 1.7 mg/dL) were seen in seven patients (29%) while on study. New cases of thrombocytopenia (worst value 39×109/L) and neutropenia (worst value 0.50×109/L) developed in one patient each during the study; these were assessed as unrelated to study drug. There were 15 discontinuations (63%): three due to unrelated deaths (two congestive cardiac failure, one subdural hemorrhage); four patients withdrew consent for unknown reasons; two from MDS progression; five because of adverse events (AEs), four of which were related to study drug (one diarrhea, two increased SCr, one increased liver enzymes) and one unrelated (splenic infarct); and one from unsatisfactory therapeutic effect. There were 14 serious AEs reported in 11 patients; 13/14 were considered unrelated to study drug; 1/14 (severe diarrhea/lower abdominal cramping) was related to study drug and the patient completely recovered within 1 day.Conclusions: Sequential LIC measurements in this MDS cohort demonstrated a significant decrease by month 6 and further decreases by month 12 in patients who completed 1 year of treatment. LPI normalized in 80% of the patients. Two thirds of this heavily transfused population discontinued the trial mainly due to disease-related complications; four patients discontinued due to drug-related AEs. Larger studies are continuing to evaluate the clinical benefit of DFX in patients with MDS. [Display omitted]

GUIDELINES FOR THE TRANSFUSION OF RED CELLS

The following recommendations, which aim at standardising and rationalising clinical indications for the transfusion of red cells in Belgium, were drawn up by a working group of the Superior Health Council. To this end, the Superior Health Council organised an expert meeting devoted to "Guidelines for the transfusion of red cells" in collaboration with the Belgian Hematological Society. The experts discussed the indications for red cell transfusions, the ideal red cell concentrate, the practical issues of administering red cells, and red cell transfusions in patients in a critical condition. The recommendations formulated by the experts were validated by the working group with the purpose of harmonising red cell transfusion in Belgian hospitals

A Prospective Randomized Trial of Acute Normovolemic Hemodilution Compared to Standard Intraoperative Management in Patients Undergoing Major Hepatic Resection

Hepatic resection is the most effective treatment for many malignant and benign conditions affecting the liver and biliary tree. Despite improvements, major partial hepatectomy can be associated with considerable blood loss and transfusion requirements. Transfusion of allogeneic blood products, although potentially life-saving, is associated with many potential complications. The primary aim of this study was to determine if acute normovolemic hemodilution (ANH), an established blood conservation technique, reduces the requirement for allogeneic red cell transfusions in patients undergoing major hepatic resection. One hundred thirty patients undergoing major hepatic resection (> or =3 segments) were prospectively randomized to undergo either ANH or standard anesthetic management (STD). In the ANH group, intraoperative blood collection was performed to a target hemoglobin of 8.0 g/dL. Low central venous pressure anesthetic technique was used intraoperatively for both groups. A standardized transfusion protocol was applied to all patients intraoperatively and throughout the hospital stay. From April 2004 to March 2007, 63 patients were randomized to ANH and 67 to STD. Demographics, diagnoses, liver function, extent of resection, intraoperative blood loss, operative time, incidence and grade of complications, and length of hospital stay were similar between the 2 groups. ANH reduced the overall allogeneic red cell transfusion rate by 50% compared with STD [12.7% (n = 8) vs. 25.4% (n = 17), respectively; P = 0.067. ANH patients were less often transfused intraoperatively (n = 1, 1.6%) compared with the STD group (n = 7, 10.4%) (P = 0.036), had higher postoperative hemoglobin levels (P = 0.01), and tended to require fewer red cell units overall (28 vs. 47 units). In patients with intraoperative blood loss > or =800 mL, ANH reduced not only the allogeneic red cell transfusion rate (18.2% vs. 42.4%, P = 0.045) but also the proportion of patients requiring fresh frozen plasma (21.1% vs. 48.3%, P = 0.025). For patients undergoing major liver resection, ANH is safe, effectively reduces the need for allogeneic transfusions, and should be considered for routine use. Given the modest transfusion rate in the STD arm, future efforts should attempt to target ANH use to patients most likely to benefit.

The Genomics of New Drugs in Sickle Cell Disease

The quality of life of patients with sickle cell disease in developed countries has improved significantly over the past two decades. Currently available measures to prevent the painful crises and the complications of the disease include the use of penicillin prophylaxis, antipneumonococcal vaccine, folate administration, chronic red cell transfusions in patients with cerebrovascular disease, iron chelating agents, fetal hemoglobin-enhancing agents, such as hydroxyurea, decitabine and butyrate, drugs that augment the endogenous nitric oxide levels and agents that restore red cell dehydration. Sickle cell patients show a broad phenotypic expression and a great variability in treatment response. Genetic association studies, which attempt to link polymorphisms with certain disease phenotypes and drug response, are taking the first steps in aiding individualized therapy in sickle cell patients in order to enhance efficacy and reduce toxicity.

A randomized trial of tranexamic acid in combination with cell salvage plus a meta-analysis of randomized trials evaluating tranexamic acid in off-pump coronary artery bypass grafting

We sought to evaluate the effectiveness of tranexamic acid in off-pump coronary artery bypass grafting surgery, either when used in combination with mechanical cell salvage or when used alone. One hundred patients were randomized to either 2 g of tranexamic acid as an intravenous bolus before sternotomy or to placebo. Intraoperative and postoperative cell salvage was used in all patients. The primary end point was early postoperative blood loss (within 4 hours). To evaluate the efficacy of tranexamic acid in isolation, we also performed a meta-analysis of 4 randomized trials identified from a systematic literature search. The primary end point of the meta-analysis was red cell transfusion. In our randomized trial patients in the tranexamic acid group had a significant reduction in early postoperative blood loss, (median difference, 50 mL; 95% confidence interval, 15-100 mL; P < .01); however, there was no reduction in the frequency of blood component transfusion. Patients in the placebo group received a significantly larger volume of autotransfused red cells (median difference, 120 mL; 95% confidence interval, 0-220 mL; P = .02). The meta-analysis demonstrated a significant reduction in red cell transfusions in patients receiving tranexamic acid compared with those receiving placebo (risk ratio, 0.48; 95% confidence interval, 0.24-0.97; P = .041). There was also a reduction in the frequency of any allogeneic blood component transfusion, as well as a highly significant reduction in postoperative blood loss, in patients receiving tranexamic acid (P < .001). Tranexamic acid reduces blood loss and transfusion requirements in off-pump coronary artery bypass grafting surgery. A reduction in allogeneic blood transfusion was not evident in the presence of perioperative cell salvage. These data support the routine use of tranexamic acid in off-pump coronary artery bypass grafting surgery.

Tranexamic acid reduces allogeneic red cell transfusions in patients undergoing total knee arthroplasty: results of a meta‐analysis of randomized controlled trials

The delayed bleeding associated with total knee arthroplasty (TKA) may be a result of a tourniquet-induced imbalance of the procoagulant and fibrinolytic systems. There are conflicting results in the literature about tranexamic acid (TA) infusion in reducing postoperative blood loss and the number of transfused red cells (RBC) units. A meta-analysis was performed to summarize the results of different research studies. Randomized controlled trials reported through October 2004 were retrieved, and nine studies met the criteria for meta-analysis. Summary odds ratio (OR) of allogeneic transfusion and a weighted mean difference (WMD) of transfusions per patient in TA-treated group versus placebo group were calculated across studies. The use of TA significantly reduced the proportion of patients requiring blood transfusion (summary OR, 0.10; 95% CI, 0.06-0.18; p < 0.00001) and the number of RBC transfusions per patient (WMD, -1.72; 95% CI, -2.11 to -1.33; p < 0.00001) when compared with patients who received placebo. Our meta-analysis shows that the use of TA for patients undergoing TKA is effective in reducing the requirements of allogeneic blood transfusion.

Parenteral iron therapy options

Parenteral iron therapy is occasionally necessary for patients intolerant or unresponsive to oral iron therapy, for receiving recombinant erythropoietin therapy, or for use in treating functional iron deficiency. There are now three parenteral iron products available: iron dextran, ferric gluconate, and iron sucrose. We summarize the advantages and disadvantages of each product, including risk of anaphylaxis and hypersensitivity, dosage regimens, and costs. The increased availability of multiple parenteral iron preparations should decrease the need to use red cell transfusions in patients with iron-deficiency anemia.

Therapeutic challenges in childhood sickle cell disease. Part 1: current and future treatment options.

Therapeutic challenges in childhood sickle cell disease. Part 1: current and future treatment options.

Practice Trends in the Management of Low Hematocrit in the Acute Rehabilitation Setting

To examine current clinical practice regarding the management of anemic patients in the acute rehabilitation setting. Ninety-four medical directors of inpatient rehabilitation units were surveyed on their use of transfusion thresholds and human recombinant erythropoietin. Factors affecting their clinical decision making were assessed. The majority of physicians responded that they recommend red cell transfusion in patients with a hematocrit <25%. When a history of cardiovascular disease and advanced age was present, more physicians were likely to transfuse at higher hematocrit levels. Forty-six percent of physicians reported recommending the use of human recombinant erythropoietin in anemic patients. Only 30% of respondents classified their clinical management of anemia as evidence based. Clinical practice guidelines should be developed to aid the rehabilitation medicine specialist in the management of anemic patients in the acute rehabilitation setting. Further study of the relationship between hematocrit level, tolerance for therapeutic exercise, and long-term functional outcome is indicated.

Desmopressin for minimising perioperative allogeneic blood transfusion.

Public concerns regarding the safety of transfused blood have prompted re-consideration of the use of allogeneic (from an unrelated donor) red blood cell (RBC) transfusion, and a range of techniques designed to minimise transfusion requirements. To examine the evidence for the efficacy of desmopressin (1-deamino-8-D-arginine-vasopressin), in reducing perioperative blood loss and the need for red cell transfusion in patients who do not have congenital bleeding disorders. Articles were identified by: computer searches of OVID MEDLINE, EMBASE, and Current Contents (to August 2000) and web sites of international health technology assessment agencies (to May 1998). References in the identified trials and review articles were checked and authors contacted to identify additional studies. Randomised controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomised to DDAVP, or to a control group, who did not receive the intervention. Trial quality was assessed using criteria proposed by Schulz et al. (1995) and Jadad et al. (1996). The principal outcomes were: the number of patients exposed to red cells, and the amount of blood transfused. Other clinical outcomes are detailed in the review. Fourteen trials of DDAVP (N=1034) reported data on the proportion of patients exposed to allogeneic RBC transfusion. In subjects treated with DDAVP the relative risk of exposure to peri-operative allogeneic blood transfusion was 0.98 (95%CI: 0.88 to 1.10) compared with control. In DDAVP-treated patients the relative risk of requiring re-operation due to bleeding was 0.56 (95%CI: 0.18 to 1.73). There was no statistically significant effect overall for mortality and non-fatal myocardial infarction in DDAVP-treated patients compared with control (RR=1.53: 95%CI: 0.58 to 4.05) and (RR=1.52: 95%CI: 0.67 to 3.49) respectively. There is no convincing evidence that desmopressin minimises perioperative allogeneic RBC transfusion in patients who do not have congenital bleeding disorders. These data suggest that there is no benefit of using DDAVP as a means of minimising perioperative allogeneic RBC transfusion. This meta-analysis had 90% power to detect a relative risk reduction of at least 17% for receiving a red cell transfusion at alpha = 0.05 (two-sided).

Early changes in hemoglobin and hematocrit levels after packed red cell transfusion in patients with acute anemia.

Equilibration of hemoglobin concentration after transfusion has been estimated to take about 24 hours, but some studies have shown that earlier measurements reflect steady-state values in persons who have not bled recently. This study was aimed at assessing the changes over time in hemoglobin concentration after transfusion in acutely anemic patients because of recent bleeding. Thirty-two normovolemic patients recovering from an acute bleeding episode who were no longer thought to be bleeding and who received a 2-unit red cell transfusion were studied. At baseline and 15, 30, 60, and 120 minutes and 24 hours after transfusion, hemoglobin concentration and hematocrit values were measured. The administration of 2 units of packed red cells elicited a 24-hour increase of 22.4 +/- 6.8 g per L in hemoglobin concentration. Hemoglobin values were not different at any of the defined posttransfusion times. Hematocrit levels experienced similar changes over time. Agreement between 15-minute and 24-hour values was excellent, as only 6 percent of patients exhibited a clinically significant difference (> 6 g/L) between the hemoglobin measurements. Hemoglobin and hematocrit values rapidly equilibrate after transfusion in normovolemic patients who are recovering from an acute bleeding episode. This fact would allow a rapid assessment of the effects of transfusion and of the recurrence of bleeding in patients remaining at risk.