RESUMEN
OBJECTIVES: To examine the performance of a rural ambulance trust during two time periods, 1996/97 and 2001, with respect to achieving standards for ambulance journey times and delivery of clinical care for patients with suspected acute myocardial infarction (AMI). METHODS: Audit datasets on two cohorts of patients with chest pain and suspected AMI were assembled by the Lancashire Ambulance Service NHS Trust in north west England: 3706 patients during 1996/97 and 3423 in 2001. They were transported to four hospitals. The analyses covered journey timings, role of rapid response vehicles (RRV), and clinical procedures and the results were compared with prevailing national standards. RESULTS: Hourly and daily usage patterns were similar in the two periods. During 1996/97 the national rural target of 95% of response times being within 19 minutes was achieved (96% of calls), unlike the target of 50% within eight minutes (45.3% of calls). During 2001, 2684 (78.4%) calls had response times within eight minutes thus exceeding the revised national target of 75%. RRVs were despatched for 1214 (35.5%) of calls in 2001, and the mean response time (SD) for these vehicles was significantly shorter than for front line ambulances (0:05:53 (0:02:49) versus 0:07:04 (0:04:19), p<0.001), likewise the mean call to hospital time (0:32:38 (0:09:28) v 0:35:01 (0:12:09), p<0.001). Patients in 2001 were more likely to be given aspirin by the ambulance crews (74% of cases), while the rate of cannulation was lower. CONCLUSION: A significant improvement has been achieved in the performance of ambulance services in Lancashire since 1996, because of recently introduced strategies, notably RRVs, and in the presence of more demanding national standards and targets.
Asunto(s)
Ambulancias , Enfermedad Coronaria/terapia , Servicios Médicos de Urgencia/normas , Análisis de Varianza , Distribución de Chi-Cuadrado , Urgencias Médicas , Servicios Médicos de Urgencia/organización & administración , Inglaterra , Predicción , Humanos , Población Rural , Factores de TiempoRESUMEN
The paper discusses how a decision analytic framework has been used by an English health authority in relation to the commissioning of ambulance cardiac services. Strategies for the management by ambulance personnel of victims of cardiac arrest and persons with acute chest pain of cardiac origin were modelled in a decision-event tree, and a bibliographic database established. The international research literature prior to 1997 was searched in order to derive probability values for the tree. However, after checking whether the subgroupings of results in the papers were in accordance with the variables in the tree, the number of useful papers on acute chest pain was found to be only two. In the almost complete absence of information--even from small observational studies--on the management of the great majority of patients with cardiac symptoms transported by ambulance, the local ambulance service and the main providers of hospital services in the district are now collaborating in field studies of cardiac care in order to improve the inputs into the model.
Asunto(s)
Ambulancias , Sistemas de Apoyo a Decisiones Administrativas , Cardiopatías/terapia , Evaluación de Necesidades , Medicina Estatal/organización & administración , Algoritmos , Servicios Contratados , Árboles de Decisión , Medicina Basada en la Evidencia , Humanos , Transporte de Pacientes , Reino UnidoRESUMEN
STUDY OBJECTIVE: To produce a priority list for purchasers to use when purchasing elective care in the speciality of orthopaedics so that efficiency in health care purchasing (that is, maximising the benefit per unit of resource available for the resident population) can be achieved. DESIGN: The study used cost utility analysis in the elective speciality of orthopaedics. The diagnostic groups in the study were chosen on the basis of those conditions that constituted the greatest proportion of the orthopaedic waiting list, and consequently the greatest proportion of activity within the speciality. Costs were derived by two methods: the extra contractual referral tariff (ECR) and individual patient based costings. Outcome was assessed before surgery and again approximately six months afterwards. The outcome of the procedures was derived in two ways: Rosser and EuroQol indices. SETTING: The study took place at Wrightington hospital, a specialist orthopaedic hospital in north west England. PATIENTS: Prospective assessments were obtained from 99 patients for nine orthopaedics procedures. All the patients were individually interviewed on each occasion. Rosser and EuroQol assessments were completed for each patient by the patient and the patient's consultant before and after surgery. MAIN RESULTS: Priority lists presenting cost utility rankings for each of the procedures were derived from the patients' and consultants' assessments. CONCLUSIONS: It is feasible to generate priority lists in a systematic way. Purchasers may then use the results from these priority lists to help them maximise the benefits per unit of resource for their resident population.
Asunto(s)
Procedimientos Quirúrgicos Electivos/economía , Ortopedia/economía , Años de Vida Ajustados por Calidad de Vida , Análisis Costo-Beneficio , Procedimientos Quirúrgicos Electivos/métodos , Inglaterra , Estado de Salud , Humanos , Ortopedia/métodos , Estudios Prospectivos , Resultado del TratamientoRESUMEN
When rat kidney cortex slices were incubated with glycine or [1-14C]glycine, after correcting for metabolite changes with control slices, product formation and glycine utilization fitted the requirements of the equation: 2 Glycine leads to ammonia + CO2 + serine. Evidence is presented that degradation via glyoxylate, by oxidation or transamination, is unlikely to have any significant role in kidney glycine catabolism. It is concluded that glycine metabolism in rat kidney is largely via glycine cleavage closely coupled with serine formation. 1-C decarboxylation and urea formation with glycine in rat hepatocyte suspensions were somewhat greater than decarboxylation or ammonia formation in kidney slices, showing that in the rat, potentially, the liver is quantitatively the more important organ in glycine catabolism. There was no evidence of ammonia formation from glycine with rat brain cortex, heart, spleen or diaphragm and 1-C decarboxylation was very weak.
Asunto(s)
Glicina/metabolismo , Corteza Renal/metabolismo , Aminoácidos/metabolismo , Amoníaco/metabolismo , Animales , Benzoatos/farmacología , Ácido Benzoico , Dióxido de Carbono/metabolismo , Técnicas In Vitro , Corteza Renal/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas , Serina/metabolismo , Distribución Tisular , Urea/metabolismoRESUMEN
1. The subcellular distribution of L-serine-pyruvate aminotransferase activity in rat liver was investigated. About 80% was recovered from cell-free homogenates in a 'total-particles' fraction and the remainder in the cytosol. 2. Subfractionation of the particles by differential sedimentation and on sucrose density gradients showed a distribution for serine-pyruvate aminotransferase activity closely matching that observed for mitochondrial marker enzymes. 3. A study of the solubilization of enzymes from combined subcellular particles by digitonin at various concentrations also indicated a common subcellular location for serine-pyruvate aminotransferase and established mitochondrial enzymes. 4. The increase in liver serine-pyruvate amino-transferase activity induced by glucagon injection was accounted for as an increased mitochondrial activity.
Asunto(s)
Hígado/enzimología , Transaminasas/metabolismo , Animales , Digitonina , Glucagón/farmacología , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/enzimología , UltracentrifugaciónRESUMEN
1. In rats, liver 4-hydroxy-2-oxoglutarate aldolase and hydroxyproline oxidase activities are maximal in the suckling period. 2. Liver activities for 4-hydroxy-2-oxoglutarate aldolase, alanine-glyoxylate aminotransferase, serine-pyruvate aminotransferase and serine dehydratase, but not hydroxyproline oxidase, are increased in rats on a high-fat, carbohydrate-free diet. 3. It is suggested that 4-hydroxy-2-oxoglutarate may be a significant source of glyoxylate for glycine and hence glucose formation. 4. Mammalian liver hydroxyproline oxidase activity is higher in carnivorous species; necessary, perhaps, to metabolise a relatively large influx of hydroxyproline on a flesh diet.
Asunto(s)
Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Oxo-Ácido-Liasas/metabolismo , Envejecimiento , Animales , Animales Recién Nacidos , Gatos , Cricetinae , Perros , Femenino , Hurones , Feto , Ácidos Cetoglutáricos/metabolismo , Riñón/enzimología , Riñón/crecimiento & desarrollo , Hígado/enzimología , Hígado/crecimiento & desarrollo , Masculino , Mesocricetus , Ratones , Especificidad de Órganos , Embarazo , Conejos , Ranidae , Ratas , Ratas Endogámicas , Especificidad de la Especie , PorcinosRESUMEN
1. A rough inverse correlation between liver serine dehydratase activity and species body size was observed with mammals. This was not found for glutamate, malate or lactate dehydrogenase, fumarase or aspartate-2-oxoglutarate aminotransferase. Serine dehydratase (and certain liver aminotransferases showing a similar species-size dependence) may have a role in the stimulation of heat production. 2. Cold-exposed rats showed a 3-4 fold increase in serine dehydratase activity. 3. No liver serine dehydratase was measurable in amphibia. 4. In mammals high liver serine-pyruvate aminotransferase is associated with a flesh-eating dietary habit. High activity was found in amphibia and goldfish. A gluconeogenic role is suggested.
Asunto(s)
L-Serina Deshidratasa/metabolismo , Hígado/enzimología , Transaminasas/metabolismo , Animales , Peso Corporal , Especificidad de la Especie , VertebradosRESUMEN
The specific radioactivity of urinary hippurate glycine was determined after injecting guinea pigs with benzoate and either dl-[2-(14)C]glutamate or dl-[5-(14)C]glutamate. The isotope dilution factor for the formation of [(14)C]glycine was significantly greater (30%) with C-2 labelled glutamate. With either form of labelled glutamate the hippurate glycine was largely carboxyl-group labelled. The observations suggest a route for the incorporation of glutamate carbon into glycine that involves C-5 but not C-2. A hypothesis for glycine biosynthesis from l-glutamate is advanced, consistent with these findings, that includes conversion of l-glutamate to 4-hydroxy-2-oxoglutarate, the scission of the latter to glyoxylate and pyruvate, and the formation of glycine by transamination.
Asunto(s)
Glutamatos/metabolismo , Glicina/biosíntesis , Hipuratos/biosíntesis , Aminoácidos/aislamiento & purificación , Animales , Benzoatos/metabolismo , Radioisótopos de Carbono , Glicina/orina , Glioxilatos/metabolismo , Cobayas , Hipuratos/orina , Ácidos Cetoglutáricos/metabolismo , Piruvatos/metabolismo , Succinatos/análisisRESUMEN
1. The distribution of l-alanine-glyoxylate aminotransferase activity between subcellular fractions prepared from rat liver homogenates was investigated. The greater part of the homogenate activity (about 80%) was recovered in the ;total-particles' fraction sedimented by high-speed centrifugation and the remainder in the cytosol fraction. 2. Subfractionation of the particles by differential sedimentation and on sucrose density gradients revealed a specific association between the aminotransferase and the mitochondrial enzymes glutamate dehydrogenase and rhodanese. 3. The aminotransferase activities in the cytosol and the mitochondria are due to isoenzymes. The solubilized mitochondrial enzyme has a pH optimum of 8.6, an apparent K(m) of 0.24mm with respect to glyoxylate and is inhibited by glyoxylate at concentrations above 5mm. The cytosol aminotransferase shows no distinct pH optimum (over the range 7.0-9.0) and has an apparent K(m) of 1.11mm with respect to glyoxylate; there is no evidence of inhibition by glyoxylate. 4. The mitochondrial location of the bulk of the rat liver l-alanine-glyoxylate aminotransferase activity is discussed in relation to a pathway for gluconeogenesis involving glyoxylate.