Predictors of transfusion for spinal surgery in Maryland, 1997 to 2000

BACKGROUND: The purpose of this study was to identify preoperative patient, hospital, and surgeon characteristics associated with transfusion for spinal surgery. STUDY DESIGN AND METHODS: Discharge data were obtained from 39 Maryland hospitals for adult patients (n = 3988) who had a primary procedure code for spinal surgery between July 1997 through June 2000, and with these codes, surgeons and hospitals were characterized by annual patient volume. Outcome variables included any allogeneic transfusion, any transfusion, RBCs, autologous blood, FFP, or platelet transfusion. Logistic regression was used for univariate and multivariate analyses. RESULTS: Characteristics independently associated with an increased risk of receiving any allogeneic transfusion (n = 786) included age >54 (OR, 1.6; 95% CI, 1.3-2.1), age >66 (OR, 2.7; 95% CI, 2.0-3.5), female sex (OR, 1.6; 95% CI, 1.2-2.0), diabetes with chronic complications (OR, 2.5; 95% CI, 1.3-4.9), and metastatic tumor (OR, 4.9; 95% CI, 2.3-10.5), emergency room admission (OR, 2.3; 95% CI, 1.4-3.8), and greater hospital volume (OR, 4.0; 95% CI, 1.8-8.6). Characteristics independently associated with increased autologous transfusions (n = 574) included white race (OR, 1.7; 95% CI, 1.2-2.4), female sex (OR, 1.4; 95% CI, 1.1-1.8), and greater surgeon volume (OR, 3.5; 95% CI, 1.4-9.1). DISCUSSION: This information can be used to provide informed risk-benefit discussions with patients regarding the risk for blood transfusion as well as to target high-risk patients and institutions for interventions to reduce the risk of exposure to blood components.     

In vitro and in vivo persistence of reticulocytes from donor red cells

BACKGROUND: Reticulocytes are important in the phenotyping of transfused patients. Reticulocytes can persist in blood units for the shelf life of the unit. STUDY DESIGN AND METHODS: Temperature dependence of reticulocyte persistence was examined in vitro at 4, 24, and 37 degrees C by using thiazole orange staining and flow cytometric analysis. Two-color flow cytometric analysis was used to evaluate the persistence of donor reticulocytes in transfused patients. RESULTS: Flow cytometric analysis using thiazole orange demonstrated that persistence of reticulocytes in units of stored CPDA-1 blood was temperature-dependent. Reticulocytes disappeared over 13 and 6 days at 24 degrees C and 37 degrees C, respectively, but at 4 degrees C the reticulocyte count changed little over 35 days. Two-color flow cytometric analysis of reticulocyte antigens was used to follow donor reticulocytes in 14 transfusion events in nine different patients. Donor reticulocytes persisted through 24 hours in 75 percent of the patients and were detectable at 48 hours in three patients. CONCLUSION: This study demonstrates that reticulocytes persist during refrigerated storage; they are detectable in the circulation of most recipients for the first 24 hours after transfusion and in the circulation of a few recipients after 48 hours. These findings may have relevance for separation techniques based on reticulocyte density in samples drawn shortly after transfusion and for evaluation of reticulocyte counts in patients with hematologic abnormalities.     

Ancillary Care in Community-Based Public Health Intervention Research

Community-based public health intervention research in developing countries typically takes place not in clinics but in people''s homes and other living spaces. Research subjects and their communities may lack adequate nutrition, clean water, sanitation, and basic preventive and therapeutic services.Researchers often encounter unmet health needs in their interactions with individual subjects and need ethical guidelines to help them decide how to respond.To what extent do researchers have an ethical obligation to provide ancillary care—health care beyond what is necessary to ensure scientific validity and subjects'' safety? We discuss a case example from Nepal and propose a simple 2-step sequence of questions to aid decision making.PEOPLE LIVING IN LOW-REsource settings around the world suffer disproportionately from preventable or treatable conditions, including respiratory infections, diarrheal diseases, malnutrition, neonatal infections, and complications of pregnancy and childbirth. To alleviate the global burden of disease, it is crucial to develop and evaluate new approaches to the delivery of health interventions in low-resource settings. To this end, community-based public health intervention (CBPHI) research is designed to assess the effectiveness of health interventions delivered in the absence of advanced clinical facilities. For example, a group of simple preventive and curative newborn care interventions, delivered to women in their homes by community health workers, reduced neonatal mortality by 34%, as compared with services normally available in rural Bangladesh.¹In CBPHI research, by contrast with similar efforts based in facilities such as clinics, semiskilled local community health workers and data collectors typically carry out research activities in people''s homes and other functional living spaces. (CBPHI research may be, but is not necessarily, community-based participatory research, in which community members collaborate actively in all phases of research, from the choice of objectives to the communication of results.²) Host communities may lack adequate nutrition, clean water, sanitation, and basic preventive and therapeutic health services. CBPHI research workers therefore often encounter unmet health needs in their interactions with subjects. For instance, pregnant women invited to enroll in studies of interventions directed at neonatal health outcomes may lack access to basic antenatal care such as micronutrient supplementation.To what extent, and for what reasons, do CBPHI researchers have an ethical duty to respond to such unmet needs on the part of subjects in their studies?³ This is a question of obligations to provide ancillary care. Ancillary care is health care that research subjects need but that is not necessary to secure scientific validity in meeting research objectives or to prevent or redress research-related harms.^4,5 Ethical analysis of obligations to provide ancillary care has focused mainly on clinic-based trials.^4–8 Here we extend this ethical analysis to CBPHI research. After briefly reviewing key elements of the current ancillary care discussion, we outline 3 attributes that frequently occur together in CBPHI research and illustrate these attributes with a case example from Nepal. We propose a simple 2-step sequence of questions to aid decision making about the provision of ancillary care, and we illustrate the practical implementation of this sequence through analysis of the case example.