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1.
Artículo en Inglés | MEDLINE | ID: mdl-17100219

RESUMEN

PURPOSE: Business process redesign (BPR) is used to implement organizational transformations towards more customer-focused and cost-effective care. Ideally, these innovations should be carefully described and evaluated so that "best practices" can be re-applied. To investigate this, available evidence was collected on patient care redesign projects. DESIGN/METHODOLOGY/APPROACH: The Ebsco Business Source Premier, Embase and Medline databases were searched. Studies on innovations related to re-engineering patient care that used before-after design as minimum prerequisites were selected. General characteristics, logistic parameters and other outcome measures to determine the objectives and results and interventions used were looked at. FINDINGS: A total of 86 studies that conformed to the criteria were found: a minority mentioned measurable parameters in their objectives. In the majority of studies, multiple interventions were combined within single studies, making it impossible to compare the effects of individual interventions. Only three randomized controlled trials were found. Furthermore, inconsistencies were noted between the study objectives and the reported results. Many more issues were reported in the results than were mentioned in the study aims. It would appear that publications were hard to find owing to a lack of specific MeSH headings. Nearly 7,500 abstracts were scanned and from these it was concluded that clear and univocal research methods, terms and reporting guidelines are advisable and must be developed in order to learn and benefit from BPR innovations in health care organizations. ORIGINALITY/VALUE: This appears to be the first time available evidence about redesign projects in hospitals has been systematically collected and assessed.


Asunto(s)
Medicina Basada en la Evidencia , Administración Hospitalaria , Atención Dirigida al Paciente , Programas Nacionales de Salud , Países Bajos , Innovación Organizacional
2.
Ned Tijdschr Geneeskd ; 147(38): 1860-5, 2003 Sep 20.
Artículo en Holandés | MEDLINE | ID: mdl-14533500

RESUMEN

OBJECTIVE: (a) To describe trends in the number of heart interventions performed over time, (b) to determine the length of waiting lists for elective heart interventions in the Netherlands according to the monthly survey of the Supervisory Committee for Heart Interventions in the Netherlands [Begeleidingscommissie Hartinterventies Nederland (BHN)], (c) to compare the length of the waiting lists with existing standards, and (d) to determine the reliability of the waiting list survey. DESIGN: Prospective. METHOD: Data were obtained from the monthly waiting list survey of the 13 heart centres in the Netherlands (1 January 1999-30 November 2002) and from the intervention registry (1 January 1999-30 June 2001), which was complete for 10 centres. Both the survey and the maintenance of the registry are carried out by the Supervisory Committee for Heart Interventions in the Netherlands. RESULTS: (a) The number of percutaneous coronary interventions performed in the Netherlands has increased. The number of cardiothoracic interventions remained stable. (b) The number of patients waiting for a percutaneous coronary intervention is increasing by 16% per annum. In November 2002 there were 751 patients on the waiting list. The number of patients waiting for a cardiothoracic intervention increased by 20% per annum until August 2001 and since then there has been a decrease of 21% per annum. In November 2002, 1557 patients were on the waiting list. (c) The percentage of patients treated within existing standards has fallen to 78% for percutaneous coronary interventions and to 53% for cardiothoracic interventions. (d) The length of the waiting list and the waiting times obtained in the survey concurred with the data taken from the intervention registry. CONCLUSIONS: The length of the waiting list for heart interventions has increased and complies increasingly less with existing standards. The monthly waiting-list survey was a reliable method of determining the length of waiting lists for elective heart interventions.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/estadística & datos numéricos , Listas de Espera , Angioplastia Coronaria con Balón/estadística & datos numéricos , Puente de Arteria Coronaria/estadística & datos numéricos , Procedimientos Quirúrgicos Electivos/estadística & datos numéricos , Humanos , Países Bajos , Estudios Prospectivos , Factores de Tiempo
3.
Ned Tijdschr Geneeskd ; 144(22): 1058-62, 2000 May 27.
Artículo en Holandés | MEDLINE | ID: mdl-10850108

RESUMEN

The stroke consensus dating from 1991 had to be revised, because of the introduction of new developments in the treatment of patients with stroke. More than 50 representatives from 25 professions and institutions participated. Under methodological assistance of the Dutch Institute for Healthcare Improvement CBO separate working groups (diagnosis, treatment, organization of care, rehabilitation/education, implementation and cost-effectiveness) studied the literature and translated the results into recommendations with explanatory text. The strength of scientific evidence was classified. During a national public meeting the results were discussed. In the field of guideline development cost-effectiveness analyses and specific attention for implementation are new. Care on a stroke unit decreases the risk of mortality, life-long disabilities, and dependence on permanent care with about 20%. Regional stroke services should be instituted, in which continuity and efficient care can be guaranteed. Very early thrombolysis with recombinant tissue plasminogen activator strongly decreases the number of patients dying, or remaining care-dependent in a selected group of appropriate patients. Secondary prevention (lifestyle measures, acetylsalicyclic acid, treatment of hypertension and hypercholesterolaemia, and surgery of the carotids) may decrease the number of residual strokes and myocardial infarctions. In the occurrence of cerebral ischaemia and atrial fibrillation oral anticoagulants are indicated. Early intensive rehabilitation increases the chance of recovery. Silent cognitive defects may hinder rehabilitation. The extensive guideline summarises the scientific literature about treatment of patients with stroke and should serve as a basis for local protocols and appointments.


Asunto(s)
Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/terapia , Terapia Trombolítica/métodos , Enfermedad Aguda , Análisis Costo-Beneficio , Fibrinolíticos/uso terapéutico , Hospitales Especializados/organización & administración , Humanos , Países Bajos , Educación del Paciente como Asunto , Activadores Plasminogénicos/uso terapéutico , Guías de Práctica Clínica como Asunto , Prevención Primaria/métodos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/tratamiento farmacológico , Rehabilitación de Accidente Cerebrovascular , Factores de Tiempo , Activador de Tejido Plasminógeno/uso terapéutico
4.
AJR Am J Roentgenol ; 173(6): 1469-75, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10584784

RESUMEN

OBJECTIVE: MR angiography may be an appropriate tool to screen for unruptured intracranial aneurysms. Feasibility, test characteristics, and interobserver agreement in evaluation of MR angiograms were assessed by members of the MARS (Magnetic resonance Angiography in Relatives of patients with Subarachnoid hemorrhage) Study Group. SUBJECTS AND METHODS: We screened 626 first-degree relatives of a consecutive series of 193 patients with subarachnoid hemorrhage examined at two institutions. We used MR imaging and MR angiography (three-dimensional time-of-flight imaging at both institutions and additional three-dimensional phase-contrast imaging at one institution). Three observers independently assessed the MR angiograms. Conventional angiography was performed in relatives with possible or definite aneurysms on MR angiography and was considered the standard of reference. RESULTS: Thirty-three aneurysms were found in 25 (4%; 95% confidence interval [CI], 3-6%) of 626 relatives. Thirteen (8%) of 169 relatives who refused screening had MR-related reasons; an additional six persons could not be screened because of contraindications for MR imaging (pregnancy, n = 1; claustrophobia, n = 5). The positive predictive value of MR angiography was 100% (95% CI, 79-100%) for "definite" aneurysms and 58% (95% CI, 28-85%) for "possible" aneurysms. Sensitivity of MR angiography was estimated at 83% (95% CI, 65-94%) and specificity at 97% (95% CI, 94-98%). Interobserver agreement in the evaluation of MR angiograms was poor (kappa < .30), probably because different diagnostic strategies used by individual observers resulted in different use of the assessment category "possible aneurysm." CONCLUSION: MR angiography is a feasible screening tool for detection of intracranial aneurysms. Positive predictive value, sensitivity, and specificity are acceptable when at least two neuroradiologists independently assess MR angiograms.


Asunto(s)
Aneurisma Intracraneal/diagnóstico , Angiografía por Resonancia Magnética , Tamizaje Masivo , Adulto , Arterias Cerebrales/patología , Estudios de Factibilidad , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Procesamiento de Imagen Asistido por Computador , Aneurisma Intracraneal/genética , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Factores de Riesgo , Hemorragia Subaracnoidea/diagnóstico
5.
Stroke ; 30(8): 1628-31, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10436112

RESUMEN

BACKGROUND AND PURPOSE: We sought to determine whether there are mutations in the COL3A1 gene in patients with saccular intracranial aneurysms with a type III collagen deficiency and whether there is an association between a marker in the COL3A1 gene and saccular intracranial aneurysms. One of the heritable factors possibly involved in the pathogenesis of saccular intracranial aneurysms is a reduced production of type III collagen, demonstrated earlier by protein studies. METHODS: We analyzed the type III collagen gene in a group of 41 consecutive patients with an intracranial aneurysm, of whom 6 patients had shown a reduced production of type III collagen in cultured diploid fibroblasts from a skin biopsy. RESULTS: No mutations could be demonstrated in the COL3A1 gene, especially not in the globular N- and C-terminal regions. A null allele was excluded in 25 patients, including 1 patient with a decreased type III collagen production. No differences were found between 41 patients and 41 controls in allele frequencies of a DNA tandem repeat polymorphism located in the COL3A1 gene. CONCLUSIONS: It is concluded that the COL3A1 gene is not directly involved in the pathogenesis of most of intracranial aneurysms. The reduced type III collagen production in cultured fibroblasts found in some patients with an intracranial aneurysm is not explained by the present study and needs further exploration.


Asunto(s)
Colágeno/deficiencia , Colágeno/genética , ADN/análisis , Regulación de la Expresión Génica , Aneurisma Intracraneal/genética , Alelos , Biopsia , Células Cultivadas , Exones , Fibroblastos/citología , Fibroblastos/metabolismo , Marcadores Genéticos/genética , Humanos , Aneurisma Intracraneal/metabolismo , Mutación Puntual , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Pronóstico , ARN Mensajero/análisis , Piel/citología , Piel/metabolismo , Secuencias Repetidas en Tándem
6.
Stroke ; 29(8): 1531-8, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9707188

RESUMEN

BACKGROUND AND PURPOSE: Greater availability and improvement of neuroradiological techniques have resulted in more frequent detection of unruptured aneurysms. Because prognosis of subarachnoid hemorrhage is still poor, preventive surgery is increasingly considered as a therapeutic option. Elective surgery requires reliable data on its risks. Therefore, we performed a meta-analysis on the mortality and morbidity of surgery for unruptured intracranial aneurysms. METHODS: Through Medline and additional searches by hand, we retrieved studies on clipping of unruptured (additional, symptomatic, or incidental) aneurysms published from 1966 through June 1996. Two authors independently extracted data. We used weighted linear regression for data analysis. RESULTS: We included 61 studies that involved 2460 patients (57% female; mean age, 50 years) and at least 2568 unruptured aneurysms (27% >25 mm, 30% located in the posterior circulation). Mortality was 2.6% (95% confidence interval [CI], 2.0% to 3.3%). Permanent morbidity occurred in 10.9% (95% CI, 9.6% to 12.2%) of patients. Postoperative mortality was significantly lower in more recent years for nongiant aneurysms and aneurysms with an anterior location; the last 2 characteristics were also associated with a significantly lower morbidity. CONCLUSIONS: In studies published between 1966 and 1996 on clipping of unruptured aneurysms, mortality was 2.6% and morbidity was 10.9%. In calculating the pros and cons of preventive surgery, these proportions should be taken into account.


Asunto(s)
Aneurisma Intracraneal/mortalidad , Aneurisma Intracraneal/cirugía , Complicaciones Posoperatorias/mortalidad , Adolescente , Adulto , Anciano , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Morbilidad , Análisis Multivariante , Resultado del Tratamiento
7.
Neurology ; 50(4): 895-901, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9566369

RESUMEN

OBJECTIVE: To describe risk factors and explore mechanisms of ischemic strokes after general surgery. BACKGROUND: Strokes follow general surgery in about 0.08% to 2.9% of cases. Patients with previous cerebrovascular disease, atrial fibrillation, hypertension, advanced age, or atherosclerosis were found to have an increased risk. Knowledge of factors involved may guide physicians in determining the overall risk of surgery. METHODS: This case-control study was performed in a referral center. A total of 61 patients identified through a computerized database with ischemic strokes after surgical procedures-excluding heart, brain, vessels, or neck-between July 1986 and July 1996 were studied. Procedures included 11 urogenital, 16 gastrointestinal, 17 orthopedic, 12 pulmonary, and 5 other. A total of 122 randomly selected controls were matched for age, sex, procedure, and year of procedure. Main outcome measures included arterial territory, timing, risk factors, and perioperative events. Differences were expressed as adjusted odds ratios (AOR) with 95% confidence limits (CL), using multivariate conditional logistic analyses for matched case-control design. RESULTS: Arterial territory included 37 middle cerebral artery, 11 posterior circulation, 7 borderzone, and 6 multiple. Median procedure to stroke interval was 2 days (range, 0 to 16); 10 patients had intraoperative strokes. Three major risk factors emerged: previous cerebrovascular disease (AOR 12.57, 95% CL 2.14/73.70), chronic obstructive pulmonary disease (COPD) (7.51, 1.87/30.12), and peripheral vascular disease (PVD) (5.35, 1.25/22.94). After adding stroke-related factors, PVD (14.70, 2.01/107.71) and COPD (10.04, 1.90/53.14) remained the strongest variables; blood pressure (1.05, 1.01/1.10) and urea (1.04, 1.01/1.07) contributed slightly. Hypotension did not contribute. Four patients (6.6%) and no controls had diffuse intravascular coagulation (p = 0.01). Four stroke patients had myocardial infarction (6.6% versus 0%; p = 0.01). CONCLUSIONS: Ischemic strokes after general surgery most commonly occur after an asymptomatic interval. Previous cerebrovascular disease, COPD, and PVD greatly increase the risk. Hypotension rarely accounts for postoperative strokes. Major comorbidity of the patient at risk seems more important than complicating events during surgery.


Asunto(s)
Isquemia Encefálica/complicaciones , Isquemia Encefálica/epidemiología , Trastornos Cerebrovasculares/epidemiología , Trastornos Cerebrovasculares/etiología , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Arterias Cerebrales , Infarto Cerebral/epidemiología , Circulación Cerebrovascular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Factores de Riesgo
8.
Ann Neurol ; 43(4): 494-8, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9546331

RESUMEN

A case-control study was carried out to investigate whether type III collagen deficiency plays a role in the pathogenesis of spontaneous cervical arterial dissections. In 16 patients with spontaneous cervical arterial dissections and in 41 healthy controls, protein analysis of type III collagen (ratio of type III/type I collagen) was performed. Furthermore, single-stranded conformation polymorphism/heteroduplex analysis was used to investigate the type III collagen gene in the 16 patients with spontaneous cervical dissections to detect mutations. The ratios of type III/type I collagen in the controls ranged from 5.5 to 19.8% (median, 10%). The ratios of type III/type I collagen in the patients with spontaneous cervical arterial dissections ranged from 3.2 to 17.9% (median, 9.3%). Two patients had a low ratio of type III/type I collagen (<5.5%). No abnormalities suggesting a mutation in the gene of type III collagen were demonstrated in any of the 16 patients. Our findings are in keeping with the hypothesis that a reduced production of type III collagen may contribute to the formation of spontaneous cervical arterial dissections in some patients. The absence of a responsible mutation indicates that the coding sequence of the type III collagen gene is not involved.


Asunto(s)
Disección Aórtica/genética , Enfermedades de las Arterias Carótidas/genética , Arteria Carótida Interna , Colágeno/deficiencia , Colágeno/genética , Arteria Vertebral , Adulto , Disección Aórtica/diagnóstico por imagen , Biopsia , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Estudios de Casos y Controles , ADN/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ácidos Nucleicos Heterodúplex/genética , Polimorfismo Conformacional Retorcido-Simple , Radiografía , Piel/metabolismo , Piel/patología
9.
J Neurol ; 243(5): 405-9, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8741081

RESUMEN

Brief screening tests would be convenient for the measurement of cognitive impairment in stroke patients. In these patients aphasia can interfere with test procedures. To evaluate the feasibility of examining cognitive functions in stroke patients we examined 129 patients with an ischaemic stroke using the CAMCOG, a standardised neuropsychological screening test, after an interval of at least 3 months. Most patients (88%) were able to complete the CAMCOG. Patients with severe aphasia were significantly more likely to have an abnormal CAMCOG score than patients without aphasia [relative risk (RR) 4.0, 95% confidence interval (CI) 2.8-5.8]. The group of patients with moderate aphasia was not at higher risk of having an abnormal CAMCOG score than patients without aphasia (RR 1.4, 95% CI 0.6-2.8). Looking for other factors that might correlate with the scores, logistic regression analysis revealed age as the only significant factor for the prediction of the CAMCOG score (odds ratio 4.0, 95% CI 1.2-13.2). We concluded that the CAMCOG can conveniently be used for screening cognitive functions in patients with cerebral infarcts, even if there is moderate aphasia.


Asunto(s)
Afasia/etiología , Isquemia Encefálica/psicología , Trastornos del Conocimiento/diagnóstico , Tamizaje Masivo/métodos , Pruebas Neuropsicológicas , Isquemia Encefálica/complicaciones , Estudios de Factibilidad , Femenino , Hospitales , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad
10.
Neurosurgery ; 29(3): 434-7; discussion 437-8, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1922712

RESUMEN

The screening of asymptomatic individuals in families with intracranial aneurysms has been advocated to detect unruptured aneurysms before a major hemorrhage occurs. We report a 39-year-old male member of a large Dutch family, with a documented history of intracranial aneurysms, who suffered a subarachnoid hemorrhage 2 years after cerebral digital subtraction angiography using intravenously administered contrast medium showed no abnormalities. Conventional arteriography demonstrated three intracranial aneurysms measuring 3 x 3 mm. Potential alternative screening procedures are discussed.


Asunto(s)
Aneurisma Intracraneal/diagnóstico por imagen , Hemorragia Subaracnoidea/etiología , Adulto , Angiografía de Substracción Digital , Angiografía Cerebral , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/genética , Masculino , Tamizaje Masivo , Rotura Espontánea
11.
Stroke ; 21(4): 626-32, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2326845

RESUMEN

We describe two patients with cerebrovascular complications of Ehlers-Danlos syndrome type IV. A 16-year-old girl with spontaneous internal carotid artery dissection and a 46-year-old woman with aneurysmal subarachnoid hemorrhage and multiple aortic dissections were both deficient in collagen type III, analyzed in cultured skin fibroblasts. To our knowledge, spontaneous carotid artery dissection associated with collagen type III deficiency has not been reported previously. Early clinical recognition of this syndrome is of great importance in view of the hazards of angiography and surgery. Collagen type III deficiency plays a role in the pathogenesis of intracranial saccular aneurysms and may also be involved in the pathogenesis of carotid cavernous fistulas and dissections of the cervical arteries.


Asunto(s)
Trastornos Cerebrovasculares/complicaciones , Síndrome de Ehlers-Danlos/complicaciones , Adolescente , Angiografía Cerebral , Trastornos Cerebrovasculares/diagnóstico por imagen , Colágeno/análisis , Colágeno/clasificación , Síndrome de Ehlers-Danlos/clasificación , Síndrome de Ehlers-Danlos/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Linaje , Piel/análisis
12.
Eur Arch Otorhinolaryngol ; 247(4): 199-201, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2198064

RESUMEN

We report the case history of a 54-year-old man who developed a fatal neurological disorder 4 years after a successful tympanoplasty with homograft pericardium. The final diagnosis of this case was Creutzfeldt-Jakob disease. This infectious spongiform encephalopathy is probably caused by a slow virus that can be transmitted by transplantation materials. The possible accidental transmission of Creutzfeldt-Jacob disease by the use of homograft materials in otologic surgery is discussed.


Asunto(s)
Síndrome de Creutzfeldt-Jakob/transmisión , Pericardio/trasplante , Timpanoplastia , Corteza Cerebral/patología , Cialito , Síndrome de Creutzfeldt-Jakob/patología , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Conservación de Tejido , Trasplante Homólogo
15.
Rev Pneumol Clin ; 40(1): 63-7, 1984.
Artículo en Francés | MEDLINE | ID: mdl-6326247

RESUMEN

In 1958 a mediastinal tumor was discovered in an asymptomatic patient. The tumor was resected and diagnosed as a nonchromaffin chemodectoma. Additionally an oesophageal abnormality was discovered but not treated. At subsequent follow-ups the mediastinum never appeared normal and the heart size progressively increased. In 1974 a small opacity appeared in the left lung. In 1975 the patient was operated: a pulmonary osteochondroma, a pericarditis and an intrapericardial aortopulmonary chemodectoma were discovered. The oesophagus was not explored. In july 1979 an inoperable epidermoid carcinoma of the main bronchus of the left lung was discovered and the patient died in september 1979. There was no hypertension and no catecholamine excess. A post-mortem section was refused. After the recent description by Carney of the triad: extra-adrenal paraganglioma, lung chondroma and gastro-intestinal leiomyo(sarco)ma, we feel that our patient could present this syndrome and that the oesophageal tumor could be a benign leiomyoma. However the exact diagnosis of the oesophageal lesion is still unknown.


Asunto(s)
Neoplasias Esofágicas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias del Mediastino/diagnóstico , Neoplasias Primarias Múltiples/diagnóstico , Adulto , Condroma/diagnóstico , Femenino , Humanos , Leiomioma/diagnóstico , Paraganglioma Extraadrenal/diagnóstico
16.
Thorax ; 32(2): 203-9, 1977 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-194350

RESUMEN

In 1958 a mediastinal tumour was discovered in an asymptomatic woman with a history of vomiting and an oesophageal anomaly which had not been treated. A tumour of the anterosuperior mediastinum in relation to the aortic arch was extirpated and proved to be a chemodectoma or non-chromaffin paraganglioma. At subsequent follow-ups the mediastinum was never normal and the heart size progressively increased, the oesophageal anomaly remaining unchanged. A small opacity appeared in the left lung in 1974. An operation performed in 1975 revealed an osteochondroma in the lung, pericarditis, and an intrapericardial chemodectoma. The oesophagus was not explored. An intrathoracic chemodectoma is rare. The importance of angiography in its diagnosis is emphasised. Malignant degeneration is seldom observed. Therapy is surgical, the tumour being radioresistant. The possibility to be considered in our patient was either relapse of the tumour with degeneration or multiple localisations of the tumour.


Asunto(s)
Neoplasias del Mediastino/patología , Paraganglioma Extraadrenal/patología , Adulto , Condroma/patología , Femenino , Neoplasias Cardíacas/patología , Humanos , Neoplasias Pulmonares/patología , Neoplasias del Mediastino/diagnóstico por imagen , Metástasis de la Neoplasia , Paraganglioma Extraadrenal/diagnóstico por imagen , Radiografía
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