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61.
Neonates have low levels of antithrombin. Inadequate anticoagulation during cardiopulmonary bypass (CPB) due to low antithrombin activity may result in a poor preservation of the coagulation system during bypass. We hypothesize that antithrombin replacement to neonates prior to CPB will preserve the hemostatic system and result in less postoperative bleeding. A randomized, double‐blinded, placebo‐controlled pilot study of antithrombin replacement to neonates prior to CPB was conducted. Preoperative antithrombin levels determined the dose of recombinant antithrombin or placebo to be given. Antithrombin levels were measured following the dosing of the antithrombin/placebo, after initiation of bypass, near the completion of bypass, and upon intensive care unit admission. Eight subjects were enrolled. No subject had safety concerns. Mediastinal exploration occurred in two antithrombin subjects and one placebo subject. Antithrombin activity levels were significantly higher in the treated group following drug administration; levels continued to be higher than preoperatively but not different from the placebo group at all other time points. Total heparin administration was less in the antithrombin group; measurements of blood loss were similar in both groups. A single dose of recombinant antithrombin did not maintain 100% activity levels throughout the entire operation. Although no safety concerns were identified in this pilot study, a larger trial is necessary to determine clinical efficacy.  相似文献   
62.
The study compares team and primary nursing modes of organization of nursing care on three related variables, namely: nurse-related behaviour and quality of care, philosophy of care and job satisfaction for nurses. The historical dimension and evolution of modes of care, quality of care, philosophy of care and theories of job satisfaction are discussed within the context of the study. The literature and previous research studies conducted on team and primary nursing are reviewed and comparisons of the two are made. Analysis of data collected yielded results which are compared for differences and benefits between team and primary nursing. The results of the study suggest that when compared to team nursing mode of organization of care, primary nursing affords increased quality of care, a more coherent philosophy of nursing and increased job satisfaction for nurses. Methodological problems are examined and implications for policy explored.  相似文献   
63.
The objective of this study was to evaluate the need for mandatory hospital admission of all pediatric patients with minor head injury (MHI) and negative computed tomographic (CT) scans for head injury. The study was a retrospective chart review of all patients admitted to a pediatric trauma service over a period of 4 years. MHI was defined as blunt head trauma with a Glasgow Coma Scale (GCS) score of 15 and a nonfocal neurological examination. Only patients < or = 13 years of age and with a negative head CT scan were included, and during hospitalization all patients were observed for delayed complications. A total of 197 patients met the inclusion criteria. The patients' mean age was 7.1 years, with a range of 2 months to 13 years. The most common mechanisms of injury were being struck by a motor vehicle while walking (82 patients), and falling (75 patients). No complications were observed, and although persistent symptoms occurred in 5 patients, they did not delay discharge. We conclude that pediatric patients with MHI and negative CT scans of the head do not require routine admission for observation for delayed complications.  相似文献   
64.
BACKGROUND: The indications for transfusion have never been evaluated in an adequately sized clinical trial. A pilot study was conducted to plan larger clinical trials. STUDY DESIGN AND METHODS: Hip fracture patients undergoing surgical repair who had postoperative hemoglobin levels less than 10 g per dL were randomly assigned to receive 1) symptomatic transfusion: that is, transfusion for symptoms of anemia or for a hemoglobin level that dropped below 8 g per dL or 2) threshold transfusion: that is, patients receive 1 unit of packed RBCs at the time of random assignment and as much blood as necessary to keep the hemoglobin level above 10 g per dL. Outcomes were 60-day mortality, morbidity, functional status, and place of residence. RESULTS: Among 84 eligible patients enrolled, mean (± SD) prerandomization hemoglobin was 9.1 (± 0.6) g/ dL. The median number of units transfused in the threshold transfusion group was 2 (interquartile range, = 1–2), and that in the symptomatic transfusion group was 0 (6; interquartile range, = 0–2) (p < 0.001). Mean hemoglobin levels were approximately 1 g per dL higher in the threshold group than in the symptomatic group: for example, on Day 2, 10.3 (± 0.9) g per dL versus 9.3 (± 1.2) g per dL, respectively (p < 0.001). At 60 days, death or inability to walk across the room without assistance occurred in 16 (39.0%) of the symptomatic transfusion group and 19 (45.2%) of the threshold transfusion group. Death occurred by 60 days in 5 (11.9%) of the symptomatic transfusion group and 2 (4.8%) in the threshold transfusion group (relative risk = 2.5; 95% CI, 0.5–12.2). Other outcomes were similar for the two groups. CONCLUSIONS: Symptomatic transfusion may be an effective blood-sparing protocol associated with the transfusion of appreciably fewer units of RBCs and lower mean hemoglobin levels than are associated with the threshold transfusion policy. However, it is unknown whether these two clinical strategies have comparable mortality, morbidity, or functional status. A definitive trial is needed.  相似文献   
65.
Bone marrow fibrosis is the continuous replacement of blood‐forming cells in the bone marrow with excessive scar tissue, leading to failure of the body to produce blood cells and ultimately to death. Myofibroblasts are fibrosis‐driving cells and are well characterized in solid organ fibrosis, but their role and cellular origin in bone marrow fibrosis have remained obscure. Recent work has demonstrated that Gli1+ and leptin receptor+ mesenchymal stromal cells are progenitors of fibrosis‐causing myofibroblasts in the bone marrow. Genetic ablation or pharmacological inhibition of Gli1+ mesenchymal stromal cells ameliorated fibrosis in mouse models of myelofibrosis. Conditional deletion of the platelet‐derived growth factor (PDGF) receptor‐α (PDGFRA) gene (Pdgfra) and inhibition of PDGFRA by imatinib in leptin receptor+ stromal cells suppressed their expansion and ameliorated bone marrow fibrosis. Understanding the cellular and molecular mechanisms in the haematopoietic stem cell niche that govern the mesenchymal stromal cell‐to‐myofibroblast transition and myofibroblast expansion will be critical to understand the pathogenesis of bone marrow fibrosis in both malignant and non‐malignant conditions, and will guide the development of novel therapeutics. In this review, we summarize recent discoveries of mesenchymal stromal cells as part of the haematopoietic niche and as myofibroblast precursors, and discuss potential therapeutic strategies in the specific targeting of fibrotic transformation in bone marrow fibrosis. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
66.
Cardiac disease is a risk factor for venous thromboembolism (VTE) in children. In this study, we investigated the incidence and risk factors of VTE in critically ill children with cardiac disease, who were prospectively followed-up for VTE after admission to a tertiary care pediatric intensive care unit (PICU). Risk factors were compared between VTE cases and (1) patients in the cohort who did not develop VTE and (2) the next three cardiac patients sequentially admitted to the PICU (case control). Forty-one cases of VTE were identified from 1070 admissions (3.8%). Thirty-seven percent of VTE cases were central venous catheter (CVC)–associated, and 56% of cases were intracardiac. Sixty-six percent of patients were receiving anticoagulation at the time of VTE diagnosis. Increased VTE incidence was associated with unscheduled PICU admission, age <6 months, extracorporeal membrane oxygenation, increased number of CVCs, increased number of CVC days, higher risk of mortality score, and longer PICU stay. Using logistic regression, VTE was associated with single-ventricle physiology (odds ratio [OR] 11.2, 95% CI 3.0–41.9), widened arterial-to-somatic oxygen saturation gradient (SpO2–rSO2 >30) (OR 4.3, 95% CI 1.1–16), and more CVC days (OR 1.1, 95% CI 1.04–1.13). Risk factors for VTE in critically ill children with cardiac disease include younger age, single-ventricle cardiac lesions, increased illness severity, unscheduled PICU admission, and complicated hospital course.  相似文献   
67.
目的:应用分类树模型构建重症手足口病的预测模型,并评价其应用价值。方法:整群抽取河南省郑州市某医院2013年4月至6月住院治疗的221例发病时间≤72 h的手足口病患儿为研究对象,采用CHAID分类树算法建立重症手足口病的预测模型,采用错分概率Risk值、索引图及受试者工作特征曲线评价模型的应用价值。结果:所建立的分类树模型包括3层,共9个结点,共筛选出4个解释变量:精神差、易惊、热峰≥39℃、手足抖动;其中最为重要的预测因素为精神差和易惊。模型错分概率Risk值为0.045,模型拟合的效果较好。结论:分类树模型不仅能有效地拟合重症手足口病的风险预测,还可以对变量间的交互作用进行有效的筛选。  相似文献   
68.
69.
BACKGROUND: Maternal platelet antibodies can cause fetomaternal alloimmune thrombocytopenia (FMAT), which has significant mortality and morbidity even in a first pregnancy. Prenatal diagnosis of FMAT has not previously been possible in the first affected pregnancy. STUDY DESIGN AND METHODS: Using flow cytometry, a sensitive, inexpensive test for the detection of platelet antibodies has been developed. It was adapted for use as a possible antenatal screening test, and 600 pregnant women were tested in a pilot study. RESULTS: In the study group, two women tested positive for platelet-specific IgG antibodies, one for anti-HPA- 1a and the other for anti-HPA-1a with anti-HLA. In each case, the fetus was found to be affected in utero, and treatment was initiated before successful delivery. Another woman was shown to have a platelet- reactive autoantibody without IgG specificity, and her infant was unaffected. A total of 95 (15.8%) of the women tested had HLA antibodies alone, and the majority demonstrated IgG specificity. On follow-up of 62 infants born to these women, none had thrombocytopenia; thus HLA antibodies were not shown to lead to FMAT in this study. CONCLUSION: The flow cytometry-based test for platelet antibodies can detect clinically significant maternal antibodies, and it may be that early diagnosis and treatment in utero can enhance outcome in FMAT. A population screening program is planned to determine the predictive power of this test, in addition to its sensitivity, specificity, and efficiency.  相似文献   
70.
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