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Blood transfusion policy among European pediatric intensive care physicians.

The objective of this study was to define current blood transfusion practices among European pediatric intensive care physicians treating critically ill children. A questionnaire of case scenarios was administered to members of the European Society of Pediatric and Neonatal Intensive Care (ESPNIC). Of the 258 members of the ESPNIC, 134 (51.9%) pediatric intensive care physicians completed the questionnaire. The suggested blood transfusion thresholds for case scenario 1 (post-orthopedic surgery child) ranged from <7.0 g/dl to 11 g/dl. A total of 57.3% suggested 7 g/dl, 33.6% suggested 8 g/dl, and 6.9% suggested 9 g/dl as a hemoglobin threshold for transfusion (mean, 7.54 +/- 0.75). For case scenarios 2 to 4, the suggested hemoglobin thresholds were 7 g/dl to 12 g/dl. For case scenario 2 (a child with acute respiratory distress syndrome), 22.4% suggested 8 g/dl, 15.7% suggested 9 g/dl, and 41% suggested 10 g/dl as a hemoglobin threshold for transfusion (mean, 9.40 +/- 1.27 g/dl). For case scenario 3 (a post-cardiac surgery infant), 20.1% suggested 7 g/dl, 24.6% suggested 8 g/dl, 21.6% suggested 9 g/dl, and 23.9% suggested 10 g/dl as a hemoglobin threshold for transfusion (mean, 8.72 +/- 1.24 g/dl). For case scenario 4 (a child with septic shock), 23.1% suggested 8 g/dl, 16.4% suggested 9 g/dl, and 41% suggested 10 g/dl as a hemoglobin threshold for transfusion (mean, 9.45 +/- 1.24 g/dl). The threshold for transfusion was not statistically different (P >.05) between the physicians according to their subspecialty, years of experience, or country of origin. The suggested volume of transfused blood was 10 to 15 ml/kg in 427 responses (82.6%) and 20 ml/kg in 89 responses (17.2%). Most physicians, 78/128 (60.9%), did not consider the age of the transfused blood an important factor in their decision to transfuse. Of the 106 (79.1%) physicians who detailed their considerations for elevating the threshold for transfusion, 82 (77.3%) gave a general nonspecific indication, 47 (44.3%) stated hemodynamic instability and shock, and 40 (37.7%) an ongoing bleeding. The hemoglobin threshold for blood transfusion and transfusion volume varies among European pediatric intensive care physicians, for the same patient.

Analysis of Variance↗

A preliminary study of placental umbilical cord whole blood transfusion in under resourced patients with malaria in the background of anaemia.

BACKGROUND: Malaria is an annual killer of over one million people globally and its essential co-morbidity is anaemia. Cord blood, because of its rich mix of foetal and adult haemoglobin, high platelet and WBC counts, hypo-antigenic nature, altered metabolic profile and high affinity for oxygen as well as its anti-malarial effect, is an ideal choice in malaria with anaemia, necessitating blood transfusion. METHODS: This paper presents an alternative protocol for fresh whole blood/packed cell transfusion from the hospital's biological waste resources, i.e., the placenta, after the birth of a healthy baby from a healthy mother. This collected blood was routinely transfused to patients admitted in our hospital with severe anaemia in the background of confirmed malaria. 94 units of placental umbilical cord whole blood were collected after lower uterine caesarean section (LUCS) from consenting mothers (from 1st April 1999 to April 2005), and safely transfused to 39 informed, consenting patients (age varying from 8 to 72 years). The collected volume of cord blood from each placenta (Unit) varied from 52 ml to 143 ml, with a mean packed cell volume of 48.9 +/- 4.1 SD and a mean haemoglobin concentration of 16.4 Gm percent +/- 1.6 Gm percent SD. The blood was immediately transfused after following the standard adult blood transfusion protocol of screening and cross-matching between the donor and the recipient. On occasion, the collected cord blood was preserved in the refrigerator, if no volunteer was readily available, and transfused within 72 hours of collection. RESULTS: Cord blood transfusion was tested on twenty two patients infected with Plasmodium falciparum and 17 patients with Plasmodium vivax. For inclusion in this study, the patient's plasma haemoglobin had to be 8 gm percent or less (the pre-transfusion haemoglobin in the malaria-infected patients in this series varied from 5.4 gm/dl to 7.9 gm/dl). The rise of haemoglobin within 72 hours of two units of freshly collected cord blood transfusion was 0.5 gm/dl to 1.6 gm/dl. Each patient received two to six units of freshly collected cord blood transfusion (two units at a time), depending on availability and compatibility. No clinical immunological or non-immunological reaction has been encountered in this series. CONCLUSION: Properly screened cord blood is safe for transfusion, in victims of severe malarial anaemia who need transfusion support.

Adolescent↗

Variations in transfusion practice in neonatal intensive care.

OBJECTIVE: To compare the transfusion practices between two neonatal intensive care units (NICUs) to assess the impact of local practice styles on the timing, number, and total volume of packed red cell transfusions in very low birth weight infants. To derive multivariate models to describe practice and to identify potential areas for improvement in the future. METHODOLOGY: We reviewed phlebotomy losses and transfusion rates between two NICUs (A and B) for 270 consecutive admissions of birth weight < 1500 g. We stratified for birth weight and for illness severity by the Score for Neonatal Acute Physiology (SNAP). Measures of short-term outcome were compared. We derived multivariate models to describe and compare the practices in the two NICUs. RESULTS: Patients in NICU A had smaller phlebotomy losses than those in NICU B. A lower percentage of the patients in NICU A (65% vs 87%) received transfusions, but they tended to receive a greater total volume per kg per patient (67 mL/kg vs 54.8 mL/kg). Transfusion timing differed between the NICUs; in NICU A only approximately one-half of their transfusions occurred in the first 2 weeks, whereas in NICU B almost 70% of the transfusions were given in this time period. Multivariate models showed that phlebotomy losses were significantly related to lower gestational age (GA) and higher SNAP. Hospitalization in NICU B resulted in 10.7 cc of additional losses relative to NICU A for a comparable GA and illness severity score. The volume of blood transfused per kilogram of body weight was a function of GA, SNAP, and hospital. Care practices in NICU A added an additional 19 cc of transfused volume in the first 14 days of life, and an additional 26 cc thereafter when adjusted for GA and SNAP. These differences in phlebotomy and transfusion were not associated with differences in the days of oxygen therapy or mechanical ventilation, the oxygen requirement at 28 days, the incidence of chronic lung disease, or the rate of growth by day 28. CONCLUSIONS: We identified significant differences in phlebotomy and transfusion practices between two NICUs. We found no differences in short-term outcome, suggesting that the additional use of blood in one of the NICUs was discretionary rather than necessary. Our multivariate models can be used to characterize and quantify transfusion and phlebotomy practices. By predicting which patients are likely to require multiple transfusions, clinicians can target patients for erythropoietin therapy and identify those patients for whom donor exposure can be reduced by a unit of blood for multiple use. The models may help in monitoring changes in practice as they occur.

Blood Transfusion↗

Delayed hemolytic transfusion reaction/hyperhemolysis syndrome in children with sickle cell disease.

OBJECTIVE: Alloimmunization in patients with sickle cell disease (SCD) has a reported incidence of 5% to 36%. One complication of alloimmunization is delayed hemolytic transfusion reaction/hyperhemolysis (DHTR/H) syndrome, which has a reported incidence of 11%. In patients with SCD, clinical findings in DHTR/H syndrome occur approximately 1 week after the red blood cell (RBC) transfusion and include the onset of increased hemolysis associated with pain and profound anemia. The hemoglobin (Hb) often drops below pretransfusion levels. In many reported adult cases, the direct antiglobulin test (DAT) remains negative and no new alloantibody is detected as the cause for these transfusion reactions. To date, few pediatric cases have been reported with this phenomenon. The objective of this study was to describe the clinical and laboratory findings of a case series in children who had SCD and experienced a DHTR/H syndrome at our institution. METHODS: An 11-year retrospective chart review of patients with discharge diagnosis of SCD and transfusion reaction was performed. DHTR/H syndrome was defined as the abrupt onset of signs and symptoms of accelerated hemolysis evidenced by an unexplained fall in Hb, elevated lactic dehydrogenase, elevated bilirubin above baseline, and hemoglobinuria, all occurring between 4 and 10 days after an RBC transfusion. Patient characteristics, time from transfusion, symptoms, reported DAT, new autoantibody or alloantibody formation, laboratory abnormalities, and complications were recorded. Patients with acute transfusion reactions were excluded. RESULTS: We encountered 7 patients who developed 9 episodes of DHTR/H syndrome occurring 6 to 10 days after RBC transfusion. Each presented with fever and hemoglobinuria. All but 1 patient experienced pain initially ascribed to vaso-occlusive crisis. The DAT was positive in only 2 of the 9 episodes. The presenting Hb was lower than pretransfusion levels in 8 of the 9 events. Severe complications were observed after the onset of DHTR/H: acute chest syndrome, n = 3; pancreatitis, n = 1; congestive heart failure, n = 1; and acute renal failure, n = 1. CONCLUSIONS: DHTR/H syndrome occurs in pediatric SCD patients, typically 1 week posttransfusion, and presents with back, leg, or abdominal pain; fever; and hemoglobinuria that may mimic pain crisis. Hb is often lower than it was at the time of original transfusion, suggesting the hemolysis of the patient's own RBCs in addition to hemolysis of the transfused RBCs; a negative DAT and reticulocytopenia are often present. Severe complications including acute chest syndrome, congestive heart failure, pancreatitis, and acute renal failure were associated with DHTR/H syndrome in our patients. DHTR/H in the pediatric sickle cell population is a serious and potentially life-threatening complication of RBC transfusion. It is important to avoid additional transfusions in these patients, if possible, because these may exacerbate the hemolysis and worsen the degree of anemia. DHTR/H syndrome must be included in the differential of a patient who has SCD and vaso-occlusive crisis who has recently had a transfusion.

Adolescent↗

Association of transfusion with postoperative bacterial infection.

Homologous blood transfusion has been implicated as a modulator of the host immune system in a number of clinical settings. Improved renal allograft survival is observed in patients receiving pretransplant transfusions. Decreased recurrence of active inflammatory bowel disease has been recently reported in transfused patients with Crohn's disease. Conversely, deleterious immunomodulatory effects of transfusion may explain the association between transfusion and increased susceptibility to cancer recurrence and bacterial and viral infection. Clinical studies regarding cancer recurrence and transfusion are retrospective and conflicting. There is epidemiologic evidence for more rapid progression of HIV-1 infection in heavily transfused patients. Studies on transfused surgical patients have shown transfusion to be associated with an increased frequency of postoperative bacterial infections. Some studies have come to different conclusions. These investigators have suggested that transfusion may represent a surrogate marker for other risk factors for infection. Animal models designed to control for confounding factors have supported an association between transfusion and bacterial infection severity in most, but not all, reports. Attempts to define the immunologic alterations associated with transfusion have revealed a generalized impairment of cellular immunity in both humans and animals. Although the preponderance of data supports an association between perioperative transfusion and increased susceptibility to postoperative bacterial infection, it is not certain to what extent this relationship constitutes cause and effect.

Animals↗

Cost-effectiveness of cell salvage and alternative methods of minimising perioperative allogeneic blood transfusion: a systematic review and economic model.

OBJECTIVES: To compare patient outcomes, resource use and costs to the NHS and NHS Blood Transfusion Authority (BTA) associated with cell salvage and alternative methods of minimising perioperative allogeneic blood transfusion. DATA SOURCES: Electronic databases covering the period 1996-2004 for systematic reviews and 1994-2004 for economic evidence. REVIEW METHODS: Existing systematic reviews were updated with data from selected randomised controlled trials (RCTs) that involved adults scheduled for elective non-urgent surgery. Any resource use or cost data were extracted for potential use in populating an economic model. Relative risks or weighted mean difference of each outcome for each intervention were assessed, taking into account the number of RCTs included in each outcome and intervention and the presence of any heterogeneity. This allowed indirect comparison of the relative effectiveness of each intervention when the intervention is compared with allogeneic blood transfusion. A decision analytic model synthesised clinical and economic data from several sources, to estimate the relative cost-effectiveness of cell salvage for people undergoing elective surgery with moderate to major expected blood loss. The perspective of the NHS and patients and a time horizon of 1 month were used. The economic model was developed from reviews of effectiveness and cost-effectiveness and clinical experts. Secondary analysis explored the robustness of the results to changes in the timing and costs of cell salvage equipment, surgical procedure, use of transfusion protocols and time horizon of analysis. RESULTS: Overall, 668 studies were identified electronically for the update of the two systematic reviews. This included five RCTs, of which two were cell salvage and three preoperative autologous donation (PAD). Five published systematic reviews were identified for antifibrinolytics, fibrin sealants and restrictive transfusion triggers, PAD plus erythropoietin, erythropoietin alone and acute normovolaemic haemodilution (ANH). Twelve published studies reported full economic evaluations. All but two of the transfusion strategies significantly reduced exposure to allogeneic blood. The relative risk of exposure to allogeneic blood was 0.59 for the pooled trials of cell salvage (95% confidence interval: 0.48 to 0.73). This varied by the type and timing of cell salvage and type of surgical procedure. For cell salvage, the relative risk of allogeneic blood transfusion was higher in cardiac surgery than in orthopaedic surgery. Cell salvage had lower costs and slightly higher quality-adjusted life years compared with all of the alternative transfusion strategies except ANH. The likelihood that cell salvage is cost-effective compared with strategies other than ANH is over 50%. Most of the secondary analyses indicated similar results to the primary analysis. However, the primary and secondary analyses indicated that ANH may be more cost-effective than cell salvage. CONCLUSIONS: The available evidence indicates that cell salvage may be a cost-effective method to reduce exposure to allogeneic blood transfusion. However, ANH may be more cost-effective than cell salvage. The results of this analysis are subject to the low quality and reliability of the data used and the use of indirect comparisons. This may affect the reliability and robustness of the clinical and economic results. There is a need for further research that includes adequately powered high-quality RCTs to compare directly various blood transfusion strategies. These should include measures of health status, health-related quality of life and patient preferences for alternative transfusion strategies. Observational and tracking studies are needed to estimate reliably the incidence of adverse events and infections transmitted during blood transfusion and to identify the lifetime consequences of the serious hazards of transfusion on mortality, health status and health-related quality of life.

Aminocaproates↗

Transmission of filarial infection through blood transfusion.

Microfilariae can be transmitted by blood transfusion and they may be circulated in the recipient's blood but they do not develop into adult worms. Mortality associated with transfusion associated filarial infection is not documented but it may give rise to morbidity in transfusion recipients in terms of allergic reaction. The present study was carried out to investigate the association of post transfusion reactions and filarial infections in an endemic area. About 11,752 transfusion recipients were followed up and in 15 months period, 47 (0.4%) post transfusion reactions (PTR) were reported. Routine investigations for post transfusion reaction were carried out in all 47 patients and their respective blood donor. Moreover, blood culture, microfilaria detection by concentration technique, filarial antibody and antigen detection (both by ELISA) were done in all subjects. Out of 47 patients showing post transfusion reaction, 29 (61.7%) patients developed allergic reaction. Eighteen (38.3%) patients having allergic reaction did not have previous history of blood transfusion and 14 (29.8%) of them received transfusion from blood donors who was either positive for microfilaria, filarial antigen or antibody. Microfilaremia was demonstrated in 4 (8.5%) patients and 5 (10.6%) blood donors. Microfilaria was concurrently present in 2 patients and their respective donors. Filarial antibody was detected in 27 (56.5%) patients and 26 (55.3%) blood donors but microfilaria was detected in 3 (6.4%) and 4 (8.5%) subjects, respectively. Antigen detection test correlated with microfileraemic state of subjects. The result shows that transfusion associated filarial infection may be a probable cause for transfusion-associated morbidity in endemic areas. In 14 (29.8%) patients having allergic reactions, the probable cause was transfusion-associated filarial infection. Filarial antigen detection test was found to be more useful in detecting infections. Blood donors with active history of filarial infection should be deferred from donating blood. Filarial antigen detection test may be employed as screening test for blood donors, if possible.

Animals↗

Underreporting of minor transfusion reactions in cancer patients.

BACKGROUND: Minor adverse reactions following transfusion of blood components to cancer patients are not uncommon. Reporting these minor reactions to the transfusion service needs a careful evaluation. The objectives of this study were to closely monitor the transfusion reactions that occurred and had not been reported to the transfusion service and to evaluate the process by which the medical and nursing staff recognized and managed these reactions. METHODS: We prepared a questionnaire with the nursing staff of a selected inpatient unit that addressed important questions, such as signs and symptoms during the transfusion, premedications given, process for physician notification, recommended action, and blood component implicated. Charts of the patients were reviewed, and the process was monitored for a 6-month period. RESULTS: A total of 58 cases were completed and analyzed. Platelet concentrates were transfused in 43 cases (74.1%), packed red blood cells in 9 cases (15.6%), and fresh frozen plasma in 6 cases (10.3%). Minor adverse reactions that were documented included chills in 11 cases (19.0%), low-grade fever in 11 cases (19.0%), hives and itching in 24 cases (41.4%), nausea and vomiting in 1 case (1.7%), and headaches and nonspecific mild pains in 11 cases (19.0%). Transfusions had been resumed in 27 cases (46.6%) and stopped completely in 13 cases (22.4%). Twenty-seven of 58 (46.6%) were first-time events. CONCLUSION: We conclude that underreporting of minor transfusion reactions, such as a febrile nonhemolytic transfusion reaction and allergic reactions, exists. To ensure safety to our cancer patients who are transfusion-dependent, we suggest that careful evaluation of any suspected transfusion reaction event should be referred to the transfusion medicine physicians who will evaluate each case and discuss it with the attending physician. This process will prevent detrimental, acute transfusion reactions.

Humans↗

[Blood transfusion safety in a limited resources setting: the elaboration of a rational National Blood Policy in Togo].

The demand for blood transfusion is high in subSaharan Africa because of the high prevalence of the anemia especially due to malaria and obstetrical damage. Providing a safe and confident system of transfusion requires more and more resources when, in developing countries, these are in fact limited. With a double view to improve the coverage in blood transfusion and ensure the security of blood products, the Ministry of Health of Togo launched in 1999 a series of operations for setting up a rational National Blood Transfusion Policy. The following steps were undertaken. A two-week situation analysis of the blood transfusion sector highlighted the lack of sector regulation, the multiplicity of blood unit production centres (n = 33 for a country of 56,000 km(2)) that could endanger the security of the products especially in limited resources conditions, the inadequacy in quality management in all areas of blood transfusion (insufficiency of human resources, equipment and supply, lack of procedures, etc.) and the lack of an information system on blood transfusion for retrospective survey and planning. The draft of the National Blood Transfusion Policy was then written in a week by two national consultants in accordance with the findings of the situation analysis. It was validated during a three-day multidisciplinary workshop and an ultimate validation was made by an international consultant in order to assess the adequacy of the options considered to the country's specific setting. The options retained for developing the Togolese blood transfusion sector development and which are consigned in the National Blood Transfusion Policy are as follows: development and implementation of blood transfusion regulations; reorganisation of the National Transfusion System by reducing it to 3 blood unit production centres: one in Lomé (the capital town), one in the centre of the country (Sokodé, 480 km from Lomé), and one in the Northern part (Dapaong, 870 km from Lomé); setting up of a system of blood collection, storage and distribution around these centres; promotion of voluntary and anonymous blood donation; promotion of quality assurance in the system and of good blood prescription practice; development and implementation of an appropriate and simple information system for better management; identification of a sustainable and equitable financing system in which the State must play a key role. The implementation of the National Blood Policy; and in particular the achievement of its goals requires: i) permanent State commitment; ii) the building of a rational action plan - with a financing framework for all blood transfusion partners; and iii) regular program evaluation.

Anemia↗

Placental umbilical cord blood transfusion: a new method of treatment of patients with diabetes and microalbuminuria in the background of anemia.

Diabetes mellitus is the commonest endocrine disease in all populations and all age groups. It is a syndrome of disturbed intermediary metabolism caused by inadequate insulin secretion or impaired insulin action, or both. Anemia is a common accompaniment of diabetes, particularly in those with albuminuria justifying tubulointestitial injury or reduced renal function. There are other additional factors present in diabetes, which may contribute to the development of an increased risk of anemia. Cord blood, because of its rich mix of fetal and adult hemoglobin, high platelet and WBC counts, hypo-antigenic nature, altered metabolic profile and high affinity for oxygen, may be an ideal choice for cases of diabetes with severe anemia necessitating blood transfusion. This article presents my team's experience with 78 units of placental umbilical cord whole blood (from 1 April 1999 to April 2005), collected after lower uterine cesarean section (LUCS) from consenting mothers (56 ml-138, ml mean 82 ml +/- 5.6 ml SD, median 84 ml, mean packed cell volume 49.7 +/- 4.2 SD, mean percent hemoglobin concentration 16.6 g/dl +/- 1.5 g/dl SD) and transfused to diabetes patients with microalbuminuria and severe anemia necessitating transfusion. After collection, the blood was transfused, in most cases immediately after completion of the essential norms of transfusion. In rare cases, it was kept in the refrigerator and transfused within 72 hours of collection to a suitable recipient. For inclusion in this study, the patient's percent plasma hemoglobin had to be 8 g/dl or less (the pretransfusion hemoglobin in this series varied from 5.2 g/dl to 7.8 g/dl) in the background of type two diabetes (fasting sugar 200 mg or more), along with features of microalbuminuria (albumin excretion 30-299 mg/g creatinine). This study included 39 informed consenting patients (22 males + 17 females, aged 48-74 yrs, mean 59.6 yrs). The patients were randomized into two groups: Group A (control cases N = 15, males = 8 and females = 7) and Group B (study group N = 24, males = 14 and females = 10). In Group A the rise of hemoglobin (Hgb) after two units of adult blood transfusion was 1.5 to 1.8 g/dl, as seen after a 72-hour blood sample assessment. The rise of Hgb as noted after 72 hours of two units of freshly collected cord blood transfusion was .6 g/dl to 1.5 g/dl. Each patient received two of four units of freshly collected cord blood transfusion (two units at a time), depending on availability and compatibility. Microalbuminuria was assessed in both groups after one month of treatment with transfusion and other identical support. The mean result was 152 +/- 18 m SD of albumin per gram of creatinine excreted through 24-hour urine (pre-transfusion mean excretion was 189 +/- 16 mg) in Group A and 103 +/- 16 mg SD of albumin excretion per gram of creatinine in 24-hour excretion of urine in Group B (pretransfusion mean excretion was 193 +/- 21 mg). Univariate analysis using Fisher's exact test was performed for the results of Groups A and B. The difference between Group A and B values and its comparison with the pre-transfusion microalbuminuria appeared to be statistically significant (p < less than .003). We have not encountered any clinical, immunological or non-immunological reaction so far in either group. Fetomaternal cell traffic has been implicated as the cause of scleroderma in mothers delivering male babies. In the present series, we did not see any such rare and unusual complication due to neonatal blood transfusion in the adult system in Group B patients in the six years from the initiation of the study.

Adolescent↗

Transfusion practice in medical patients.

OBJECTIVE: Blood transfusion raises serious issues of safety and economics. We therefore examined blood usage and its characteristics in medical inpatients, given the relative scarcity of existing data. DESIGN: During a 1-year period, transfusion episodes on two medical services were reviewed by five specialists for justifiability on the basis of generally agreed on guidelines. SETTING: The study was conducted at two institutions, a municipal teaching hospital where house staff deliver care and a community hospital where patients are under the direct care of private physicians. PATIENTS: Four hundred thirty-eight randomly selected transfusion episodes on the medical services of the two institutions were reviewed. MAIN OUTCOME MEASURES: The prevalence of unjustifiable transfusions based only on the information available to the managing physician at the time of transfusion. RESULTS: Eighteen percent of the 438 randomly selected transfusion episodes were viewed as not justifiable by at least four of five reviewers; another 17% were classified as equivocal because two or three reviewers judged them to be not justifiable. The most striking observation was the greater prevalence of nonjustifiable transfusion episodes at the community hospital (26% vs 16% at the teaching institution; P = .0121). Other observations included a tendency for physicians to prescribe transfusions by the numbers (at least 11% of nonjustifiable transfusions) and to overtransfuse. The routineness with which transfusion was viewed by managing physicians was also identifiable by the absence of written transfusion notes in 39% of all episodes reviewed, which incidentally raises questions about the adequacy of the medical chart's documentary functions today. CONCLUSIONS: The rate of nonjustifiable or equivocal transfusion on medical services may be as high as 35%. Reliance on numbers rather than clinical status seems to be a major problem. Education is obviously a critical issue and should also target private practitioners, who seemed to perform less well than physicians in training. Transfusion guidelines that use specific hematocrit values also need to be reexamined.

Blood Transfusion↗

Current status of transfusion triggers for red blood cell concentrates.

Clinical practice guidelines on red blood cell transfusion (RBC) are based on expert opinion, animal studies and the few human trials available. Twelve randomized controlled trials on the benefits of RBC transfusions in humans have been published. In the absence of definitive outcome studies, numerous theoretical arguments have been put forward in favor or against the classic transfusion threshold of 100 g/l. However, data from randomized controlled trials suggest that overall morbidity (including cardiac) and mortality, hemodynamic, pulmonary and oxygen transport variables are not different between restrictive (transfusion threshold between 70 and 80 g/l) and liberal transfusion strategies and that a restrictive transfusion strategy is not associated with increased adverse outcomes. In fact, a restrictive strategy may be associated with decreased adverse outcomes in younger and less sick critical care patients. The majority of existing guidelines conclude that transfusion is rarely indicated when the hemoglobin concentration is greater than 100 g/l and is almost always indicated when it falls below a threshold of 60 g/l in healthy, stable patients or more in older, sicker patients. In anesthetized patients, this threshold should be modulated by factors related to the dynamic nature of surgery such as uncontrolled hemorrhage, microvascular bleeding, etc. Another important role of RBC relates to primary hemostasis and higher triggers may be appropriate in coagulopathic patients. RBC concentrates are administered to correct inadequate oxygen delivery and/or to sustain primary hemostasis. Reliable monitors of tissue oxygenation and hemostasis will be required to study the benefits (or lack thereof) of RBC transfusions. The quest for a universal transfusion trigger, i.e., one that would be applicable to patients of all ages under all circumstances, must be abandoned. All RBC transfusions must be tailored to the patient's needs, at the moment the need arises. In conclusion published recommendations are commensurate with existing knowledge and, unfortunately, their conclusions are limited. Future research and development should focus on the determination of optimal transfusion strategies in various patient populations and on reliable monitors to guide transfusion therapy.

Blood Component Transfusion↗

ABO compatibility can influence the results of platelet transfusion. Results of a randomized trial.

Sixty consecutive patients with untreated acute leukemia alternately received either ABO-matched or ABO-mismatched random-donor platelet transfusions prepared from pooled platelet concentrate stored for 1 to 3 days. Patients were assigned randomly to receive matched or mismatched platelets as their first transfusion, and the first four transfusions were analyzed. In 40 evaluable patients, there was no significant difference (paired t test) between the 10-minute posttransfusion corrected count increments (CCI) of the initial transfusions of matched and mismatched platelets. In contrast, the second matched transfusion was significantly better than the second mismatched transfusion. This effect of ABO compatibility was particularly pronounced in a subset of patients. Six patients in whom mismatched transfusions were consistently inferior to matched transfusions had either a significant increase in anti-A or -B isoagglutinin titers following the first transfusion or elevated titers before or at the conclusion of the study. Conversely, in five patients in whom there was no apparent effect of ABO mismatching, only one had an increase in isoagglutinin titer. Platelet survival was not altered as the ratio of 18-hour to 10-minute posttransfusion CCl was 0.6 for both matched and mismatched platelet transfusions. These data demonstrate that ABO compatibility can affect the results of random-donor platelet transfusions and that patients who experience poor increments from ABO-mismatched platelets may benefit from a trial of ABO-compatible platelets before the initiation of HLA-matched platelet transfusion.

ABO Blood-Group System↗

Intraoperative autologous blood transfusion in intracranial surgery.

OBJECTIVE: The purpose of this study was to evaluate the benefits of intraoperative autotransfusion of autologous blood on the conservation of allogenic blood, including cost-effectiveness and the consequences for hemoglobin level and coagulation tests. METHODS: The Hoemonetics Cell Saver 4 autotransfusion system (Hoemonetics Corporation, MA) was used when the estimated blood loss was equal to or more than 500 ml. A total of 472 patients undergoing intracranial surgery were included in the study. RESULTS: Ninety patients (19%) received transfusions either with autologous blood or allogenic blood. Fifty-five patients (61%) received only autologous blood transfusions, 10 patients (11%) received both autologous and allogenic blood transfusions, and 25 patients (28%) received only allogenic blood transfusions. The amount of autologous blood transfused was 600 +/- 590 ml (range, 230-3000 ml). The amount of allogenic blood transfused was 3 +/- 3 units (range, 2-15 units). Autologous blood represented 68% of all blood products transfused. Mild abnormalities during coagulation tests occurred without clinical bleeding. CONCLUSION: Autologous blood transfusions were demonstrated to be safe in patients undergoing intracranial surgery and to be more cost-effective than allogenic blood transfusions. Intraoperative autologous blood transfusions may be used alone in more than half of the patients requiring transfusions during intracranial surgery and decrease the amount of allogenic blood used. Improvements in the monitoring for the need of performing this technique, as well as preoperative blood donations, would decrease the amount of allogenic blood transfused.

Adult↗

Reduction of inappropriate use of blood products by prospective monitoring of transfusion request forms.

OBJECTIVE: To determine the effect of prospective monitoring on appropriateness of transfusions of red cells, platelets and fresh frozen plasma (FFP). DESIGN: Prospective interventional study. SETTING: Royal Melbourne Hospital (a tertiary teaching hospital), Melbourne, Victoria, March-May 1996. INTERVENTION: The blood product request form was modified to incorporate indications for transfusion and clinical and laboratory data. Requests were monitored by blood bank laboratory staff for conformation with hospital transfusion guidelines; non-conforming requests were discussed with the requesting medical practitioner by the Haematology Registrar before blood products were issued. In case of disagreement, blood products were always issued. SUBJECTS: 200 consecutive transfusion episodes for each product (red cells, platelets and FFP). OUTCOME MEASURES: Appropriateness of transfusion, assessed by a Consultant Haematologist according to hospital guidelines. Rates of inappropriate transfusion episodes after intervention were compared with rates in a previous study. RESULTS: After intervention, rates of inappropriate transfusion episodes fell significantly (red cells, 16% to 3% [P = 0.004]; platelets, 13% to 2.5% [P = 0.02]; and FFP, 31% to 15% [P = 0.02]). Almost all inappropriate FFP transfusion episodes post-intervention were due to failure to demonstrate prolongation of prothrombin or activated partial thromboplastin times more than 1.5 times the control value. CONCLUSION: Prospective monitoring of request forms can reduce rates of inappropriate transfusions. High rates of inappropriate FFP transfusions possibly reflect uncertainty about appropriate laboratory criteria for FFP transfusion. While results of large prospective randomised controlled clinical trials of FFP transfusions are awaited, currently laboratory criteria can be retained, but should be applied with flexibility.

Blood Component Transfusion↗

Risks, benefits, alternatives and indications of allogenic blood transfusions.

Allogeneic red blood cell (RBC) transfusions are associated with multiple disadvantages, such as limited availability, high costs, multiple risks and side effects. In addition, large outcome studies comparing liberal (hemoglobin transfusion trigger range 9-10 g/dL) and restrictive (hemoglobin transfusion trigger range 7-9 g/dL) transfusion regimens still need to be performed for surgical patients. Different transfusion alternatives are known for the pre-, intra- and postoperative period. Autologous blood donation and erythropoietin are efficacious in the preoperative period. Intraoperatively, acute normovolemic hemodilution (ANH), cell salvage, antifibrinolytics, specific anesthetic and surgical techniques, coagulation monitoring, acceptance of minimal hemoglobin values and hopefully soon artificial oxygen carriers can reduce allogeneic RBC transfusions. In the postoperative period cell salvage, antifibrinolytics, and accepting minimal hemoglobin values represent alternatives to RBC transfusions. When treating a bleeding patient, the initial administration of crystalloids and colloids to restore and maintain normovolemia is important. RBC transfusions are recommended under the following circumstances: for hemoglobin levels <6 g/dL and for physiologic signs of inadequate oxygenation such as hemodynamic instability, oxygen extraction rate >50% and myocardial ischemia, detectable by new ST-segment depressions >0.1 mV, new ST-segment elevations >0.2 mV or new wall motion abnormalities by transesophageal echocardiography. The aim of this article is to review the efficacy, risk and side effects of RBC transfusions, to discuss transfusion alternatives and to summarize current indications for RBC transfusions. This information will help the physician to judiciously use RBC transfusions when they are indeed indicated.

Adult↗

Decreasing transfusion exposure risk during extracorporeal membrane oxygenation (ECMO).

Extracorporeal membrane oxygenation (ECMO) is a lifesaving therapy for neonatal pulmonary hypertension but carries a significant risk for transfusion-related complications. Packed red blood cell (PRBC) and platelet exposure were quantified and reviewed in 17 ECMO survivors prior (Group I, n = 9) and subsequent to (Group II, n = 8) changes in transfusion protocols. Blood product requirements included ECMO circuit priming, maintenance of haematocrit > 0.40 or platelet count > 50 x 10(9)/l, and colloid volume expansion. Group I was exposed to 13.8 +/- 10.2 (x +/- SD) different PRBC units. In Group II, multiple transfusions from single donor units decreased exposure 71% to 3.9 +/- 0.7 units (P < 0.05). Decreases in blood withdrawn (11%) and transfusion volume (7%) were coincident with a 15% reduction in mean bypass time. Platelet volume transfusion decreased from 159 +/- 213 to 93 +/- 64 ml using volume-reduced platelet packs. Total transfusion exposure decreased 59% from 20.8 +/- 17.8 units to 8.6 +/- 2.4 donor units. No transfusion complications occurred during the aggregate 1,926 h on bypass. We conclude that neonates on ECMO have a significant transfusion exposure risk increasing with prolonged duration of ECMO therapy. In addition we noted that concentrated platelet packs decreased transfusion volume by 41%, and multiple PRBC transfusions from single donor units decreased donor exposure by 71% while both strategies decreased the overall transfusion exposure risk by 59%.

Blood Component Transfusion↗

[Transfusion problems in surgery and anesthesiology. The causes, consequences, prevention and treatment of perioperative anemia].

INTRODUCTION: The classical indication for blood transfusion is the correction of oxygen delivery failure, and the elimination of tissue ischaemia. Such indications in the surgical and anesthesiological practice are the acute haemorrhagic states (trauma, acute gastrointestinal bleeding, intraoperative hemorrhage), as well as diseases associated with chronic blood loss (occult bleeding caused by malignancies, and ulcerating processes etc.). The traditional surgical and anesthesiological viewpoint has adopted a remarkably liberal approach to the indication of blood transfusion, and a whole range of its subtle, medium-long term adverse effects has been taken into account only recently. The purpose of this review was to analyze the causes and pathophysiological consequences of perioperative anemia and blood loss, as well as to reconsider the proper indications of blood transfusion in the view of immunological sequela. The most recent data on the transfusion related immuno-depression and immunomodulation are summarized. The authors wish to provide clues for the definition of "transfusion trigger", in addition, methods available for the clinical practice to reduce blood demand and to restore oxygen transport capacity during surgical and anesthesiological interventions are revisited. Based on the review of the literature and the personal experience of the authors the practical recommendations concerning the administration of blood and blood products should be summarized as follows: 1. Blood transfusion is rarely indicated if the hemoglobin level is above 10 g/dl, and in fact always necessary if it is less than 6 g/dl, especially, if the anemia developed acutely. 2. The "transfusion trigger" is subject to continued debate, and whether a particular patient with intermediary (6-10 g/dl) Hb levels should be transfused or not must be assessed in the perspective of the potential complications initiated by the inadequate oxygenation. 3. If major co-morbidity (e.g. emphysema, ischaemic heart disease) is present, 10 g/dl Hb, in case of respirator dependency 12 g/dl Hb levels justify the administration of transfusion. If feasible, the beneficial effects of allogenous blood sparing methodologies should be utilized. CONCLUSIONS: Although the National Blood Supply Service is excellently organized in Hungary, the current clinical practice is not satisfactory. The use of up-to-date methods at the average surgical departments is suboptimal, and due to the lack of knowledge concerning the recent advances in immunology the clinicians are far too liberal in the indication of blood transfusion. The objective is to establish a modern surgical and anesthesiological transfusion practice based on the solid understanding of immunological facts, and to modernize the continued education, as well as to improve the financing of costly blood saving methodologies.

Anemia↗