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121.
Monitoring for undertransfusion   总被引:1,自引:0,他引:1  
BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components.  相似文献   
122.
In Papua New Guinea, <it>Cryptococcus neoformans</it> var. <it>gattii</it> meningitis has a high fatality rate even in immunocompetent patients. Our retrospective study attempted to identify marker of poor prognosis. Of 88 immunocompetent patients, 30 (34.1%) died, usually soon after admission, and mortality was higher in men (<it>p</it> = 0.025) and older patients (<it>p</it> = 0.039). Death was associated with altered consciousness (<it>p</it>&lt;0.001), a history of convulsions prior to treatment (<it>p</it> = 0.002) and a maximum systolic blood pressure of &gt;150 mmHg (<it>p</it> = 0.017). These data suggest that death results from raised intracranial pressure and subsequent tentorial herniation. However, CSF opening pressure measured on admission was raised in 29/36 (81%) patients and did not predict outcome. In survivors, relapse was uncommon and was not predicted by discharge serum cryptococcal antigen titres, which were frequently raised on completion of therapy in asymptomatic patients. Mortality may be reduced if efforts are made to lower intracranial pressure in those patients who present with markers of poor prognosis.   相似文献   
123.
We compared the clinical characteristics of 50 patients from three unrelated families with familial hemiplegic migraine (FHM) linked to chromosome 19, with those of 20 patients from two families with FHM not linked to chromosome 19. We found no significant differences for age at onset, frequency and duration of attacks, duration of the paresis, and occurrence of basilar migraine symptoms. In the linked families, significantly more patients reported unconsciousness during attacks (39%, vs 15%; p<0.05) and provocation of attacks by mild head trauma (70% vs 40%; p< 0.05). In one linked family patients also displayed chronic progressive cerebellar ataxia, whereas in one unlinked family benign infantile convulsions occurred in addition to FHM. Interestingly, so far an association with cerebellar ataxia was only described in chromosome 19-linked families. FHM linked to chromosome 19 and FHM unlinked to chromosome 19 do not differ with respect to clinical features.  相似文献   
124.
125.
Objective: To identify common discrepancies and average reading grade levels for informed consent forms (ICFs) us submitted to institutional review boards (IRBs) by medical researchers.
Methods: A retrospective evaluation of ICFs as submitted to IRBs of 3 university-affiliated hospitals during a I-year period. ICF content was evaluated using a checklist of 23 requirements specified in the federal regulations governing human research. Documents then were computer-analyzed to determine the readability scores using 2 common indexes of comprehension. A discrepancy was defined as any instance in which an ICF did not address an applicable requirement in the Code of Federal Regulations.
Results: Eighty-two ICFs representing 16 medical specialties were evaluated; 8 (10%) were from emergency medicine. Eighteen ICFs (22%) were conspicuously incomplete, lacking 29 federal requirements. The mean number of discrepancies was 4.7 (95% CI, 3.9–5.5) Common omissions included: a statement about who is doing the research, number of subjects in the study, circumstances when a subject's participation may be terminated, disclosure of alternative procedures, and notice to subjects regarding new findings. The mean Flesch grade level required to read all ICFs was 13.8 (95% CI, 13.5–14.2), implying that the majority of the U.S. adult population would be unable to comprehend these forms.
Conclusion: Designing a consent form to meet all of the federal requirements while maintaining a level of reading comprehension suitable for the general population is a difficult task for investigators.  相似文献   
126.
Intra-articular Chlamydial Antigen and Inflammatory Arthritis   总被引:1,自引:0,他引:1  
Joint material from 133 patients with well-characterized inflammatoryarthritis, including individuals likely to have suffered reactivearthiritis, was studied. The majority of patients were alsoexamined for the presence of genital tract infection with Chlamydiatrachomatis. Fluorescein-conjugated monoclonal antibodies demonstratedthe presence of C. trachomatis antigen in synovial fluid celldeposits or synovial sections from inflamed knee joints of sevenpatients with reactive arthritis. The significance of thesefindings is discussed, as is the low rate of detection of chlamydialantigen in either the genital tract or the joint from patientsin this study. We emphasize the need for further work aimedat identifying the relevant immunogenic chlamydial antigensresponsible for the initiation of reactive arthritis.  相似文献   
127.
We treated patients with idiopathic membranous nephropathy (iMGN) and renal insufficiency, using: (i) (n = 15) monthly cycles of steroids (1 g methyl-prednisolone i.v. on three consecutive days, followed by oral prednisone 0.5 mg/kg/day months 1, 3 and 5) and chlorambucil (0.15 mg/kg/day months 2, 4 and 6); or (ii) (n = 17) oral cyclophosphamide (1.5-2.0 mg/kg/day for 1 year) and steroids in a comparable dose. The groups were comparable in age, renal function and levels of proteinuria. During the 6 months preceding treatment, serum creatinine levels increased from 148 +/- 50 to 219 +/- 73 mumol/l in the chlorambucil group and from 164 +/- 86 to 274 +/- 126 mumol/l in the cyclophosphamide group. Median (range) follow-ups were: chlorambucil 38 months (8-71); cyclophosphamide 26 months (5-68) (NS). Renal function improved in both groups, but the improvement was short-lived in the chlorambucil group; 12 months after starting treatment, mean serum creatinine was 6.3 mumol/l lower in the chlorambucil group and 121 mumol/l lower in the cyclophosphamide group (p < 0.01). Four chlorambucil-treated patients developed ESRD, and five needed a second course of therapy, whereas only one cyclophosphamide-treated patient developed ESRD (p < 0.05). Remissions of proteinuria occurred more frequently after cyclophosphamide treatment (15/17 vs. 5/15; p < 0.01). Side-effects necessitated interruption of treatment in six patients on cyclophosphamide and in 11 on chlorambucil (p < 0.05). In our patients, oral cyclophosphamide was better tolerated than oral chlorambucil. The suggested greater efficacy of the oral cyclophosphamide regimen needs to be ascertained by longer follow-up.   相似文献   
128.

INTRODUCTION

Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.

PATIENTS AND METHODS

A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.

RESULTS

A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).

CONCLUSIONS

Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population.  相似文献   
129.

INTRODUCTION

Accurate clinical diagnosis depends on the reliable recognition of signs and symptoms. This expertise comes from experience in seeing patients which has been traditionally gained over a long training period. Shortened specialist training (Modernising Medical Careers) has led to a greater reliance on structured teaching and skills transfer programmes. The accuracy of clinical diagnosis and the rate at which diagnostic skills improve during training is important for the assessment of trainees, and the delivery of care.

PATIENTS AND METHODS

This study assessed the accuracy of clinical diagnosis of skin lesions by two junior plastic surgery trainees. They were asked to diagnose 120 consecutive skin lesions seen in a pigmented skin lesion clinic in 2005, with the histological diagnosis being confirmed following subsequent excision. The process was repeated a year later in 2006 to enable the rate of correct diagnosis to be compared.

RESULTS

Initially, 53.3% of diagnoses were correct. A year later, this had risen to 65.0%. Twenty-two different skin pathologies were present in excised specimens, and skin cancers comprised 30%. The trainees demonstrated 93.8% sensitivity in their initial diagnosis of malignancy (95% CI, 79.2–99.2) and 97.4% a year later (95% CI, 86.5–99.9). However, specificity was 69.3% (95% CI, 58.6–78.7) in 2005 and 71.6% (95% CI, 60.5–71.4) in 2006.

CONCLUSIONS

Accuracy in the diagnosis of the wide range of skin conditions presenting to an out-patient clinic was shown to increase over a 1-year period. We feel that this improvement resulted from regular clinical exposure supported by a structured learning programme. The shortening of the specialist training period may affect the acquisition of diagnostic skills by trainees and impact on the confidence with which they commence consultant practice.  相似文献   
130.
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