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Biomedical subjects

H Hume

Publications and source records attributed to H Hume.

At least 19 recordsLinked to original sources
PubMed2004

Reaction rates in allogeneic donors.

In Canada and several other countries, there is an upper age limit for blood donation. In order to evaluate the safety of whole blood donation in elderly Canadian allogeneic donors, we analysed reaction rates following whole blood donation. Reactions rates in allogeneic whole blood donors who donated at Canadian Blood Services were reviewed retrospectively. Rates were analysed by age, donation frequency and by donation frequency for each age group. A total of 5478 reactions were available for analysis in 469 837 donors. The highest rate of mild reactions occurred in donors less than 20 years of age. Moderate and severe reactions decreased with increasing age and with donation frequency. Age-adjusted rates for mild reactions were less frequent in donors aged 66-77 years than in donors younger than 20 years. Although age-adjusted moderate reactions varied with donation frequency, after seven donations, rates were not increased for donors aged 60 years or older (0.61% for donors aged less than 20 years compared to 0.03% for donors aged 60-65 years compared to 0% for donors aged 66-71 years). Age-adjusted rates for severe reactions generally did not increase with donation frequency. These results confirm the safety of whole blood donation in regular donors who are 66-71 years of age.

Adult↗
PubMed2001

Platelet transfusion for patients with cancer: clinical practice guidelines of the American Society of Clinical Oncology.

OBJECTIVE: To determine the most effective, evidence-based approach to the use of platelet transfusions in patients with cancer. OUTCOMES: Outcomes of interest included prevention of morbidity and mortality from hemorrhage, effects on survival, quality of life, toxicity reduction, and cost-effectiveness. EVIDENCE: A complete MedLine search was performed of the past 20 years of the medical literature. Keywords included platelet transfusion, alloimmunization, hemorrhage, threshold and thrombocytopenia. The search was broadened by articles from the bibliographies of selected articles. VALUES: Levels of evidence and guideline grades were rated by a standard process. More weight was given to studies that tested a hypothesis directly related to one of the primary outcomes in a randomized design. BENEFITS/HARMS/COST: The possible consequences of different approaches to the use of platelet transfusion were considered in evaluating a preference for one or another technique producing similar outcomes. Cost alone was not a determining factor. RECOMMENDATIONS: Appendix A summarizes the recommendations concerning the choice of particular platelet preparations, the use of prophylactic platelet transfusions, indications for transfusion in selected clinical situations, and the diagnosis, prevention, and management of refractoriness to platelet transfusion. VALIDATION: Five outside reviewers, the ASCO Health Services Research Committee, and the ASCO Board reviewed this document. SPONSOR: American Society of Clinical Oncology

Cost-Benefit Analysis↗
PubMed1998

Nationwide survey of home transfusion practices.

BACKGROUND: Limited information exists on home transfusion practices. STUDY DESIGN AND METHODS: In 1995, a survey requesting data for 1994 was sent to 1273 American Association of Blood Banks (AABB) institutional members and 113 non-AABB home health care agencies that provide out-of-hospital transfusions. RESULTS: Of 943 respondents, 102 provide blood to a home transfusion program, 37 provide blood and run a home transfusion program, and 13 run a home transfusion program only, for a total of 152 (16%) with some involvement in home blood transfusions. Most of the 50 respondents with a home transfusion program are licensed by their state and accredited by the Joint Commission on Accreditation of Healthcare Organizations. All respondents have written policies for home transfusion, and 90 percent require a signed informed-consent document before initiating transfusions in the home. Most have policies requiring that there be a second adult and a telephone in the home, that the home be deemed safe for transfusion, that the patient's physician be readily available, and that the patient have had prior transfusions. The most common component issued by the blood providers was red cells, followed by platelets. White cell-reduced components were always provided by 36 percent of respondents. The most common patient diagnosis was cancer. Home transfusions were provided primarily by registered nurses. Only 14 percent of respondents indicated that the medical director of the blood bank is responsible for approving a patient for home transfusion. A posttransfusion visit is performed by 46 percent of respondents. CONCLUSION: Although most facilities have policies for the administration of home transfusions, there remains marked heterogeneity among blood providers and transfusionists regarding home transfusion practices.

Adult↗
PubMed1997

Red blood cell transfusions for preterm infants: the role of evidence-based medicine.

Increasingly clinicians attempt to base decisions regarding patient management on the results of clinical studies in addition to expert opinion and their own practical experience. In this article, the author reviews the published studies available to assist clinicians to make evidence-based decisions in three topics related to small volume red blood cell (RBC) transfusions for preterm infants; namely, studies examining the effects of RBC transfusions on possible symptoms of anemia such as tachypnea, apnea or other cardiorespiratory irregularities, studies investigating the collection and transfusion of umbilical cord blood and finally studies addressing the duration of storage and use of additive solutions for RBCs for transfusion to neonates. Based on the review of these studies, guidelines for small volume RBC transfusions in preterm infants are suggested.

Blood Transfusion, Autologous↗
PubMed1997

A survey of Canadian neonatal blood transfusion practices.

In 1990, the Pediatric Hemotherapy Committee of the American Association of Blood Banks developed and distributed a questionnaire addressing neonatal blood transfusion practices. The same questionnaire was subsequently sent to Canadian university-affiliated hospitals (n = 92). This report describes the results of the Canadian survey. Seventy-two percent (n = 66) of institutions contacted responded. Of these 42% (n = 28) had sufficient experience with neonatal transfusions and provided sufficient data for analysis. Although the majority of stated practices did follow published guidelines, several areas of variability and/or suboptimal practices were identified. With respect to component selection and preparation, suboptimal practices included excessive pretransfusion testing, unnecessary routine washing of RBC concentrates for small-volume transfusions, routine volume reduction of platelet concentrates and the use of suboptimal granulocyte preparations. With respect to transfusion practices, a disturbingly high percentage of respondents indicated that frozen plasma would be given in situations generally considered inappropriate. There was a great deal of variability in the provision of blood components at low risk for CMV, in the use of gamma irradiation and in the platelet count used for prophylactic platelet transfusions. The data collected in this survey provide information concerning practices that require improvement, identify areas where further research is desirable and provide a basis for comparison with current and future neonatal blood transfusion practices.

Blood Transfusion↗
PubMed1995

Prophylactic versus therapeutic platelet transfusion practices in hematology and/or oncology patients.

BACKGROUND: Platelet utilization has steadily increased throughout the past three decades. At the same time, there has been very little study of the current transfusion practices. STUDY DESIGN AND METHODS: A survey was conducted of institutional members of the American Association of Blood Banks (hospitals) that were actively involved in the care of pediatric and/or adult hematology and/or oncology patients. Inquiries were made relating to the extent of prophylactic versus therapeutic use of platelets, criteria used for prophylactic transfusion of platelets and type, and dose of platelets used. Data were analyzed according to patient age and type of hospital. RESULTS: Of 786 responding hospitals, 630 (80.2%) provided sufficient data for analysis; 126 of that 630 provided care for pediatric patients. The majority (60.9%) of responding hospitals had a minimum of four hematologists and/or oncologists. Eighty-four percent of hospitals reported transfusing some apheresis platelets. The dose of platelet concentrates most frequently used for adults ranged from 6 to 10, with pools of 10 more commonly used in community hospitals. More than 70 percent of hospitals reported transfusing platelets primarily for prophylaxis: 60 percent of hospitals set the threshold platelet count for prophylactic platelet transfusion at 20,000 per microL, with approximately 20 percent each transfusing at higher and lower levels. A platelet count of 50,000 per microL was most frequently required for performance of a minor invasive procedure. CONCLUSION: The data from this study show that the majority of institutions use prophylactic platelet transfusion in both pediatric and adult hematology and/or oncology patients. However, there is considerable variation in platelet transfusion practice.

Adult↗
PubMed1995

Transfusion practices in human immunodeficiency virus-infected patients.

BACKGROUND: The reported immunomodulatory effects of transfusion raise concern about the potential for virus activation and tumor growth in human immunodeficiency virus (HIV)-infected patients. In the absence of "standards" of transfusion practice for such patients, a survey of transfusion policies among institutions specializing in the care of HIV-infected patients was performed to delineate current practices. STUDY DESIGN AND METHODS: A survey developed by the Transfusion Practices Committee of the American Association of Blood Banks was sent to 47 AIDS clinical trial units and 14 regional hemophilia centers in North America. RESULTS: Forty-three percent of centers completed the survey. Most centers observed more than 200 HIV-infected patients each. The key findings were that 1) 81 percent of centers used identical red cell transfusion criteria for HIV-infected and noninfected patients; 2) 52 percent used recombinant human erythropoietin as initial treatment for zidovudine-induced anemia, while 46 percent used recombinant human erythropoietin for anemia not associated with zidovudine; 3) 35 percent of centers used white cell-reduced blood components in lieu of cytomegalovirus (CMV)-seronegative components when administering transfusion(s) to CMV-seronegative patients; 4) 27 percent gamma-radiated cellular components, but no case of graft-versus-host disease had been observed; 5) > 85 percent of centers used monoclonal factor VIII for pediatric and adult hemophiliacs infected with HIV; 6) approximately one-third of centers routinely white cell-reduced cellular components; and 7) the most common reasons for white cell reduction included reduction of febrile reactions and CMV risk, reduction of platelet alloimmunization, and delay of immunomodulatory consequences of transfusion. CONCLUSION: There is marked heterogeneity in transfusion practice for HIV-infected patients. Modification of cellular components to achieve different objectives is routine in many centers.

Blood Transfusion↗
PubMed1993

National acceptability of American Association of Blood Banks Pediatric Hemotherapy Committee guidelines for auditing pediatric transfusion practices.

In 1989, guidelines for the auditing of pediatric transfusion practices were developed by the Pediatric Hemotherapy Committee of the American Association of Blood Banks (AABB) and made available to AABB members. A survey of members who requested the guidelines was conducted to determine how consistent the guidelines were with local transfusion practices and how useful they were for the conduct of audits. The majority of respondents indicated that the recommended audit criteria agreed with local practices and that most of them could be applied to their transfusion practice audits with little or no modification. An exception was that criteria for the transfusion of platelets to premature infants were considered by some to be too liberal. However, after review of the comments and the published information available, the committee elected not to revise the guidelines pertaining to platelet transfusions for premature infants. Bearing in mind that audit criteria are intended to identify circumstances in which transfusions are acceptable as reasonable therapy without need for further justification, rather than to serve as indications for transfusions, the AABB Pediatric Hemotherapy Committee guidelines for auditing pediatric transfusion practices are fairly representative of national practice.

Blood Banks↗
PubMed1993

National survey of neonatal transfusion practices: II. Blood component therapy.

Neonatal transfusion practices during 1989 of 452 institutions involved in transfusing infants were surveyed by questionnaire. Most respondents (77%) transfused fresh frozen plasma appropriately (ie, primarily to treat coagulation disorders). However, 11% stated that their most frequent use of fresh frozen plasma was solely to treat hypovolemia, a practice generally not recommended. Seventy-eight percent of respondents transfused platelets to treat bleeding infants with blood platelet counts of less than 50 x 10(9)/L; 84% gave platelets to sick, premature neonates with counts of less than 50 x 10(9)/L whether or not bleeding was evident. Only 35% of respondents transfused granulocytes for neonatal sepsis; most institutions used buffy coats isolated from units of blood--a product readily available, but of questionable efficacy when compared with leukapheresis granulocytes. Ninety-three percent of respondents provided blood components with low risk of transmitting cytomegalovirus: components from seronegative donors were used by 84%, leukocyte-reduced products by 6%, and a combination by 10%. Thirteen percent of respondents gave gamma-irradiated blood components to all and 46% gave them to some neonates to prevent graft vs host disease. Forty-one percent did not routinely irradiate. Ten percent of respondents used leukocyte reduction instead of gamma irradiation to prevent graft vs host disease, a practice currently not advocated. Thus, national transfusion practices for neonates are variable, controversial, and, occasionally, other than those usually recommended. Additional research and educational efforts are needed to ensure optimal transfusion therapy.

Blood↗
PubMed1993

National survey of neonatal transfusion practices: I. Red blood cell therapy.

Neonatal blood component transfusion practices during 1989 were surveyed via a questionnaire developed by the Pediatric Hemotherapy Committee of the American Association of Blood Banks. Of 1790 questionnaires mailed, 452 were selected to form the database for this analysis because they were from institutions in which neonates were transfused. Nearly all institutions contained intensive care units directed by neonatologists and were involved in the management of high-risk infants. Results from institutions serving as the primary pediatric teaching hospital of a medical school were compared with those with no medical school affiliation. Thirty-six percent of primary pediatric teaching hospitals and 52% of hospitals with no medical school affiliation performed pretransfusion testing in excess of that required, resulting in additional blood loss in neonates. Sixty-six percent of primary pediatric teaching hospitals used fresh frozen plasma to adjust the hematocrit of red blood cell concentrates prior to transfusion (a practice increasing donor exposure), compared with only 29% of hospitals with no medical school affiliation. The usual indication for small-volume red blood cell transfusions in severely ill neonates was to maintain a desired hematocrit level, whereas for stable infants, red blood cell transfusions were given to treat symptomatic anemia, rather than to maintain a predetermined hematocrit. As found in 1985, neonatal transfusion practices in 1989 were variable. However, improvements have occurred since 1985 to suggest that further research and educational efforts may serve to promote even better neonatal transfusion therapy.

Blood Component Transfusion↗
PubMed1992

Hereditary nonspherocytic hemolytic anemia due to pyruvate kinase deficiency: a prevalence study in Quebec (Canada).

Fifty-eight cases of hereditary nonspherocytic hemolytic anemia due to pyruvate kinase deficiency were collected from both laboratories that have performed the assay since 1972 and from attending physicians in the province of Quebec. Using the postal addresses of the probands, a prevalence map was constructed according to the administrative regions of the province of Quebec. The prevalence was found to be higher in eastern Quebec (1/81,838) than in western Quebec (1/139,086). Fifty probands were of French Canadian origin whereas the remaining 6 were recent immigrants.

Anemia, Hemolytic, Congenital Nonspherocytic↗
PubMed1990

Multiple small bowel perforations in leukemia secondary to Epstein-Barr virus lymphoma with survival: a case report.

This is the case report of a 4-year-old white boy who was diagnosed as having acute lymphoblastic leukemia (ALL) in November 1985. While in remission and on maintenance chemotherapy, he developed a primary Epstein-Barr virus (EBV) respiratory infection in October 1986. On October 27, 1986 a plain abdominal radiograph taken for abdominal distention showed free air. At celiotomy, multiple nodules were noted to stud the small bowel. Central necrosis of these nodules with perforations were present in the distal small bowel. Resections and end-to-end anastomoses were performed. Three days later the patient again had a similar acute abdominal episode. At reexploration, similar lesions in the liver, kidney, duodenum, proximal jejunum, and colon were found. Liver biopsy as well as intestinal resections and end-to-end anastomoses were performed, along with a loop ileostomy. Polymorphic B-cell lymphoma positive for EBV was found in the specimens. After cessation of chemotherapy and institution of abdominal radiotherapy, the hepatic and renal lesions were seen to resolve on computed tomography scan. The patient's course was complicated by the development of cervical and mediastinal abscesses that were drained, and E coli sepsis accompanied by chronic diarrhea requiring intravenous hyperalimentation. By January 1988, he appeared to be recovering. His ileostomy was closed in March 1988. Despite cessation of chemotherapy since October 1986, the patient is now well and in complete remission.

Child, Preschool↗
PubMed1990

Epstein-Barr virus polymorphic B-cell lymphoma associated with leukemia and with congenital immunodeficiencies.

Polymorphic B-cell lymphoma seen in four patients with congenital immunodeficiencies and in two patients with leukemia receiving chemotherapy was associated with the Epstein-Barr virus (EBV). The tumors had characteristic histologic features: they were polymorphic consisting of a mixture of lymphoblasts and differentiated cells including plasma cells, and areas of hemorrhagic necrosis were prominent. The tumors were either polyclonal, monoclonal, or multiclonal. Patients with congenital immunodeficiencies who developed these tumors died despite radiotherapy, corticosteroids plus acyclovir, or a combination of intravenous (IV) immunoglobulins and alpha 2 interferon. Patients with leukemia recovered when immunosuppressive drugs were discontinued and leukemia has not recurred over a period of 2 and 4 years, respectively, in the two patients.

Antineoplastic Agents↗