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1.
Radiography (Lond) ; 26 Suppl 2: S20-S26, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32753259

RESUMEN

INTRODUCTION: Always Events® are defined as "those aspects of the care experience that should always occur when patients, their family members or other care partners, and service users interact with health care professionals and the health care system". It is a quality improvement methodology that starts by asking our patients the simple question "what matters to you?" and then through coproduction, works out a way to achieve this. METHODS AND RESULTS: This article tells our story and highlights the value of undertaking an Always Event® within the Radiology department at Warrington and Halton Hospitals. It will demonstrate how this approach combines research, an evaluation of findings and implementation of those findings within a very short timeframe. Embedded within the article are comments from our staff, volunteers and patients which reflect upon their experiences, our limitations, the outcomes we achieved and the impact it has had upon our patients and staff. CONCLUSION AND IMPLICATIONS FOR PRACTICE: It was important to our patients that they would be informed of how long they would wait for their examination once they booked in at x-ray reception. By undertaking an Always Event® this process is now embedded in our departments everyday activities with over 90% of our patients now being informed of their waiting time. This continued collaboration has really emphasised the value of listening to our patients, and the benefits this can lead to. It has also encouraged a positive research culture within our department (optimisation studies, working with industry, quality projects), helping to progress our profession and resulting in a quality service for our patients.


Asunto(s)
Atención a la Salud , Personal de Salud , Mejoramiento de la Calidad , Hospitales , Humanos
3.
Eur J Anaesthesiol ; 19(10): 717-26, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12463383

RESUMEN

BACKGROUND AND OBJECTIVE: Parallels exist between the coma associated with cerebral malaria and general anaesthesia. They both produce reversible loss of consciousness. In the case of cerebral malaria and in the absence of other complications, patients recover without sequelae. General anaesthetics are so designed that patients recover from their anaesthetics very quickly and show no 'after effects'. This study compares brain function in these two clinical conditions by examining auditory- (AEPs) and median nerve somatosensory-evoked potentials (SEPs). The AEPs studied (waves Pa and Nb) are thought to arise from the primary auditory cortex and the median nerve SEPs (waves P15, N20, P25, N35, P45) from the pons, thalamus and primary somatosensory cortices. METHODS: Six comatosed patients with malaria (three males, three females) aged between 19 and 38 yr were studied in Zimbabwe. Their Glasgow Coma Scores on admission were 4, 3, 6, 7, 7 and 11. Their AEPs and median nerve SEPs were recorded daily over 4 days. The data were compared with those previously collected in the UK on patients and volunteers anaesthetized with desflurane, isoflurane, sevoflurane and propofol. RESULTS: In general, patients with cerebral malaria showed AEPs and SEPs similar to those of light to moderate anaesthesia i.e. 0.5-1.25 measure of anaesthetic potency (MAC), where 1 MAC is the minimum alveolar concentration necessary to prevent movement to surgical incision in 50% of patients. The appearance of the AEPs and SEPs bore no relationship to the degree of coma. The auditory brainstem-evoked response was retained in all degrees of coma, as would be expected. Otherwise, it would not be possible to interpret the waveform. In most instances, the early cortical complex Pa/Nb/Pb of the AER was present. When comatose patients emerged from malarial coma or were stimulated by talking loudly to them, they showed changes in the Pa/Nb/Pb complex similar to those seen on awakening from anaesthesia. The somatosensory-evoked response showed clear P15, N20 and P25 peaks at the expected latencies, and in some instances the waveforms of cerebral malaria and lightly anaesthetized volunteers were very similar. CONCLUSIONS: The sensory-evoked responses of the cerebral malaria patients recorded in this study were not markedly different from those seen in light-to-moderately anaesthetized patients and volunteers. The profound depression of the AEPs and SEPs associated with deeper levels of anaesthesia were not seen, with the exception of one patient several hours before death.


Asunto(s)
Anestesia General , Encéfalo/fisiopatología , Potenciales Evocados Auditivos/fisiología , Potenciales Evocados Somatosensoriales/fisiología , Malaria Cerebral/fisiopatología , Adolescente , Adulto , Anciano , Femenino , Escala de Coma de Glasgow , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Zimbabwe
6.
Eur J Gastroenterol Hepatol ; 10(7): 573-8, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9855081

RESUMEN

BACKGROUND: The pathological processes by which Helicobacter pylori infection leads to the development of gastroduodenal disease are still incompletely understood. Oxygen-derived free radicals are important mediators of inflammation and potential carcinogens. Furthermore, dietary studies have suggested that antioxidant vitamins may protect against gastric cancer. OBJECTIVE: To determine plasma free radical activity and antioxidant vitamin levels in dyspeptic patients and to correlate the results with H. pylori infection and tobacco smoking. SUBJECTS: Forty-three patients undergoing routine endoscopy for investigation of dyspepsia. METHODS: Plasma free radical activity was determined by measurement of thiobarbituric acid-reactive substances (TBARS). Plasma samples were also assayed for the antioxidant vitamins A, C and E. Gastroduodenal biopsies were obtained from all patients for histological examination. RESULTS: Plasma TBARS levels were significantly higher in H. pylori positive versus negative subjects (P < 0.03), smokers versus non-smokers (P < 0.04) and males versus females (P < 0.01). Multiple regression analysis revealed that after correcting for male sex and smoking there was no significant association between plasma free radical activity and H. pylori infection. Smokers had significantly lower levels of plasma vitamin C than non-smokers (P< 0.05); no differences were seen in vitamin A and E levels. Gender and H. pylori infection did not significantly affect plasma antioxidant vitamin levels. Gastroduodenal disease was present in all of the smokers compared with 67% of the non-smokers (P < 0.05); 69% of the smokers were H. pylori positive versus 53% of the non-smokers. CONCLUSIONS: Tobacco smoking and male sex, both recognized risk factors for gastroduodenal disease, appear to be the major determinants of increased plasma free radical activity in dyspeptic subjects, rather than H. pylori infection. The reason for the higher prevalence of H. pylori infection and gastroduodenal disease in dyspeptic smokers is unclear but may relate to weakened antioxidant defences.


Asunto(s)
Antioxidantes/análisis , Dispepsia/sangre , Infecciones por Helicobacter/sangre , Helicobacter pylori , Fumar/sangre , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Vitaminas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Ácido Ascórbico/sangre , Dispepsia/complicaciones , Dispepsia/microbiología , Femenino , Radicales Libres/sangre , Infecciones por Helicobacter/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Vitamina A/sangre , Vitamina E/sangre
7.
Br J Plast Surg ; 51(3): 218-26, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9664881

RESUMEN

The ability to assess viability of tissues by monitoring changes in oxygenation and perfusion during harvesting and following transfer of free and pedicled flaps is potentially important in reconstructive surgery. Rapid detection of a critical change in tissue oxygenation could enable earlier and more successful surgical intervention when such problems arise. In this study near infra-red spectroscopy (NIRS) was used to assess changes in tissue oxygenation, haemoglobin oxygenation and blood volume in a porcine prefabricated myocutaneous flap model in response to pedicle manipulations. As far as we are aware this is the first usage of a NIRS instrument to assess changes in oxygenation in a flap model which closely simulates the clinical situation. A myocutaneous flap was raised (n = 9 pigs), tubed and the flap circulation allowed to readjust for periods between 7 and 9 days. The pedicle vessels were then subjected to arterial (n = 9), venous (n = 12) and total occlusion (n = 6). Repeatable and reproducible patterns of change were measured in each case. Comparison of mean values indicated that the differences between arterial and venous, and venous and total occlusions were significant for all NIRS parameters. The monitor was easily able to detect two additional features: (i) the presence of venous congestion indicated by raised levels of deoxygenated haemoglobin and an increase in blood volume; and (ii) the presence and magnitude of reactive hyperaemia. In two flaps release of arterial or total occlusion did not result in the expected reactive hyperaemia associated with an increase in blood volume (oxygenated haemoglobin) suggestive of possible damage to the vascular bed. NIRS proved able to detect and distinguish between microcirculatory changes occurring as a result of arterial, venous or total vascular occlusion. We believe that NIRS provides a sensitive and reliable postoperative monitor of tissue viability following transfer of free and pedicled flaps. It can accurately identify different types of problems with the pedicle vessels. In addition its predictive capabilities would allow assessment of flaps buried deep to the skin. This monitor is excellent for surgical and intensive care unit monitoring since it is unaffected by light, portable and is extremely easy to use.


Asunto(s)
Supervivencia de Injerto/fisiología , Colgajos Quirúrgicos , Animales , Arteriopatías Oclusivas/metabolismo , Constricción Patológica/metabolismo , Femenino , Hemoglobinas/metabolismo , Monitoreo Fisiológico/métodos , Oxihemoglobinas/metabolismo , Cuidados Posoperatorios/métodos , Espectroscopía Infrarroja Corta/métodos , Colgajos Quirúrgicos/irrigación sanguínea , Porcinos , Enfermedades Vasculares/metabolismo
8.
Cryobiology ; 36(1): 49-60, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9500932

RESUMEN

Prolonged storage of organs for transplant results in tissue damage which may be compounded on reperfusion of the graft tissue. The effect of storage times was examined on hepatic mitochondrial oxygen consumption and activities of complexes I, II-III, IV, and V in mitochondria isolated from rat liver isografts stored for 25 min and 24 h pre- and posttransplantation. While Complex I activity was significantly (P < 0.05) inhibited under all the conditions studied, Complex II-III activity was only significantly (P < 0.05) reduced following transplantation of 24-h stored tissue. Complex IV activity remained unchanged under all the conditions studied. Although Complex V activity was significantly damaged within the first 25 min of ischemia, activity values were partially recovered to control levels following 3 h of reperfusion after transplantation. Prolonged (24 h) storage induced decreases in Complex V activity which were irrecoverable. Mitochondria subjected to 25 min ischemia alone also showed a significant (P < 0.01) decrease in NAD(+)-linked respiratory control indices due to a stimulated state 4 rate. The 24-h storage and transplantation brought about a significantly (P < 0.001) greater inhibition of respiratory control and state 3 respiration. FAD-linked respiration parameters were significantly (P < 0.05) affected in livers subjected to prolonged (24 h) storage or transplantation. These data suggest that a loss of membrane integrity coupled with an inhibition of Complexes I and V and an involvement of Complex II-III in 24-h stored hepatic transplants accounts for mitochondrial respiratory dysfunction in hepatic transplantation injury. No indication of Complex IV damage was found in this study. This study shows that damage to specific mitochondrial complexes occurs as a consequence of hypothermic ischemic injury.


Asunto(s)
Criopreservación , Trasplante de Hígado , Mitocondrias Hepáticas/metabolismo , Preservación de Órganos/efectos adversos , Adenosina Trifosfato/metabolismo , Animales , Transporte de Electrón , Flavina-Adenina Dinucleótido/metabolismo , Técnicas In Vitro , Hígado/irrigación sanguínea , Hígado/lesiones , Trasplante de Hígado/fisiología , Masculino , NAD/metabolismo , Fosforilación Oxidativa , Consumo de Oxígeno , Ratas , Ratas Endogámicas Lew , Daño por Reperfusión/etiología , Daño por Reperfusión/metabolismo , Daño por Reperfusión/prevención & control
9.
Philos Trans R Soc Lond B Biol Sci ; 352(1354): 685-96, 1997 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-9232856

RESUMEN

Near-infrared spectroscopy has primarily been used in monitoring changes in cerebral haemoglobin oxygenation and haemodynamics. However its use as a method for the assessment of tissue viability following transplantation has recently been explored experimentally in our laboratory. The ability to measure changes in oxygenation and perfusion during harvesting and following transplantation of organs or transfer of free and pedicled flaps potentially important in reconstructive surgery. We have found that near-infrared spectroscopy is extremely useful in detecting vaso-occlusive events and can accurately and reliably distinguish between arterial, venous or total occlusions. Venous congestion indicated by raised levels of deoxygenated haemoglobin with a concomitant increase in blood volume and the presence and magnitude of reactive hyperaemia are both easily recognizable features by near-infrared spectroscopy. We have shown that near-infrared spectroscopy measurements of venous congestion in kidneys (and other tissues) following prolonged storage correlate with medullary vascular congestion confirmed by angiographical and histological analysis of intrarenal perfusion. Clinically we have shown that flap perfusion can be improved by altering fluid replacement regimes and the addition of ionotropes. Cerebral near-infrared spectroscopy measurements in a liver transplant model showed statistically significant differences within minutes after the anhepatic phase in cerebral perfusion and oxygenation, between animals transplanted with ischaemically damaged livers compared to those isografted with minimally stored livers. Similarly we have found that near-infrared spectroscopy can be used as a monitor to assess the adequacy of fluid or blood replacement in haemorrhagic and hypovolaemic models. We believe that near-infrared spectroscopy provides a sensitive and reliable postoperative method for the assessment of tissue viability following the transfer of free and pedicled flaps and organs.


Asunto(s)
Supervivencia de Injerto , Trasplante de Hígado/fisiología , Trasplante/fisiología , Animales , Hemoglobinas/metabolismo , Humanos , Circulación Hepática , Trasplante de Hígado/métodos , Masculino , Oxihemoglobinas/metabolismo , Ratas , Ratas Endogámicas Lew , Espectrofotometría Infrarroja/métodos , Colgajos Quirúrgicos , Trasplante Autólogo/fisiología , Trasplante Isogénico
12.
Transplantation ; 62(5): 575-82, 1996 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8830818

RESUMEN

Hypoxic injury is a major cause of tubular necrosis in the corticomedullary junction of isolated perfused kidneys, and is ameliorated by inhibitors of active reabsorption, such as frusemide. Our objective was to determine whether frusemide has a similar effect on hypothermically stored transplanted kidneys and whether this effect is modulated by impermeant solutes included in the preservation solution. The effect of frusemide on cytochrome oxidase (cyt aa3) oxidation, renal hemodynamics, and morphology was investigated in the New Zealand White rabbit renal autograft model using near-infrared spectroscopy and light microscopy. A total of 30 kidneys were autografted in six groups. Kidneys were transplanted with or without frusemide either (1) without storage (groups 1 and 2) or after 72 hr of storage in: (2) hypertonic citrate containing mannitol (groups 3 and 4); and (3) hypertonic citrate containing polyethylene glycol (PEG) (groups 5 and 6). In unstored transplanted kidneys, frusemide infusion stimulated a significant (P < 0.05) increase in hemoglobin oxygenation, compared with untreated controls. There was a tendency for cyt aa3 to become reduced, but there were no significant differences between groups 1 and 2. After 72 hr of storage, frusemide infusion stimulated a significant increase in hemoglobin oxygenation in kidneys stored in mannitol (P < 0.005), but there was no significant change in the kidneys stored in PEG. There was a corresponding reduction in cyt aa3 in kidneys stored in mannitol (P < 0.05) but no change in those stored in PEG. These results suggest that frusemide has a significant effect on cortical hemoglobin oxygenation in transplanted kidneys and on active reabsorption in the corticomedullary junction. The selection of impermeant is important and mannitol is significantly superior to PEG in this model.


Asunto(s)
Diuréticos/farmacología , Furosemida/farmacología , Trasplante de Riñón/métodos , Riñón , Manitol , Soluciones Preservantes de Órganos , Preservación de Órganos/métodos , Polietilenglicoles , Animales , Interacciones Farmacológicas , Complejo IV de Transporte de Electrones/metabolismo , Femenino , Hemoglobinas/metabolismo , Hipotermia Inducida , Riñón/irrigación sanguínea , Riñón/metabolismo , Oxihemoglobinas/metabolismo , Perfusión , Conejos
13.
Gut ; 39(1): 31-5, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8881804

RESUMEN

BACKGROUND: Vitamin E (alpha-tocopherol) is an important endogenous antioxidant and may also act as an anticarcinogen. AIM: To determine the vitamin E status of subjects with, and without, gastroduodenal inflammation and Helicobacter pylori infection. SUBJECTS: 36 patients undergoing routine gastroscopy for investigation of dyspepsia. METHODS: High performance liquid chromatography with fluorometric detection was used to determine alpha-tocopherol values. RESULTS: In H pylori negative subjects with normal gastroduodenal histology (n = 11) median alpha-tocopherol values (ng/mg tissue weight) were significantly higher in the corpus (16.4, interquartile range (IQR) 8.9-22.6) than in the antrum (3.0, IQR 2.6-6.7, p = 0.001) or duodenum (6.7, IQR 2.5-8.4, p = 0.001). H pylori infection (n = 19) was associated with a reduction in the corpus alpha-tocopherol values (median 8.3, IQR 4.9-13.7, p < 0.05) but there was no significant change in the antral concentrations although this was the main site of inflammation and neutrophil activity. Duodenal alpha-tocopherol values were not significantly changed in the presence of duodenitis or gastric H pylori infection. alpha-Tocopherol was not detected in the gastric juice of any of the subjects. Plasma alpha-tocopherol concentrations in the H pylori negative subjects (median 10.4 mg/l, IQR 7.2-11.9) were not significantly different to the values in the H pylori positive subjects (median 11.1 mg/l, IQR 7.6-12.7). CONCLUSIONS: Concentrations of alpha-tocopherol in H pylori negative subjects are higher in the corpus than in the antrum or duodenum. In the presence of predominantly antral H pylori infection and neutrophil activity the major change seen is a reduction in corpus alpha-tocopherol values while antral concentrations are maintained. These findings may reflect a mobilisation of antioxidant defences to the sites of maximal inflammation in the stomach.


Asunto(s)
Duodeno/química , Infecciones por Helicobacter/metabolismo , Helicobacter pylori , Estómago/química , Vitamina E/análisis , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión , Femenino , Helicobacter pylori/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Vitamina E/sangre
14.
Clin Sci (Lond) ; 91(1): 51-8, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8774260

RESUMEN

1. The non-invasive method of near-infrared spectroscopy was used to measure myocardial oxygenation and haemodynamics in response to left anterior descending coronary artery occlusion in a porcine model. 2. Near-infrared spectroscopy measures changes in haemoglobin (and myoglobin) oxygenation and blood volume to yield information on tissue perfusion and flow. It also measures the redox state of cytochrome aa3, thus providing information about intracellular oxygen utilization. 3. Left anterior descending coronary artery occlusion was induced to produce periods of ischaemia lasting between 24s and 13.5 min (n = 13). The changes in deoxyhaemoglobin, oxyhaemoglobin and cytochrome aa3 measured during occlusion were all highly significant compared with baseline variation. In all occlusions (n = 13) a rapid decrease in oxyhaemoglobin concentration (-75.83 +/- 3.27 mumol/l, mean +/- SEM) with a simultaneous increase in deoxyhaemoglobin of 9.27 +/- 1.69 mumol/l was measured. The total haemoglobin concentration also fell by -71.3 +/- 5.32 mumol/l. Cytochrome aa3 was also reduced during occlusion (-8.35 +/- 1.044) mumol/l. 4. Over the range 24-60s occlusion, the magnitude of the fall in total haemoglobin and oxyhaemoglobin correlated with the duration of occlusion (P < 0.003 and 0.013 respectively). For total haemoglobin only the magnitude of the fall correlated with the increase upon release of occlusion (r = 0.89, P < 0.003). 5. Release of occlusion (n = 8) resulted in an immediate increase in the concentration of deoxyhaemoglobin at 9.88 +/- 1.06s, then total haemoglobin at 13.62 +/- 1.23s and finally oxyhaemoglobin at 29.75 +/- 5.96s. The difference between the timing of the maxima after reperfusion is significant (P < 0.002 and P < 0.007 respectively). Moreover, the time for the deoxyhaemoglobin signal to reach maximum values was found to correlate with the duration of occlusion (P < 0.04). This could be indicative of the PO2 of the ischaemic tissues and an immediate off-loading of oxygen from oxyhaemoglobin. The results are reliable, reproducible and sensitive enough to detect the kinetics of haemoglobin oxygenation from a beating heart in situ.


Asunto(s)
Enfermedad Coronaria/fisiopatología , Hemodinámica , Reperfusión Miocárdica , Oxihemoglobinas/metabolismo , Animales , Volumen Sanguíneo , Enfermedad Coronaria/sangre , Complejo IV de Transporte de Electrones/sangre , Femenino , Hemoglobinas/metabolismo , Cinética , Consumo de Oxígeno , Espectrofotometría Infrarroja , Porcinos
15.
Transplantation ; 61(5): 689-96, 1996 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8607168

RESUMEN

The significance of poor medullary reperfusion in the etiology of acute tubular necrosis during renal transplantation is poorly understood. Our objective was to determine the kinetics of renal hemoglobin oxygenation using near-infrared spectroscopy during renal transplantation, to provide a framework against which the timing of mitochondrial dysfunction could be considered. New Zealand White rabbit kidneys were flushed with hypertonic citrate solution (0-2 degrees C and autografted immediately (group 1) or stored at 0-2 degrees C for 72 hours before autografting (group 2). Changes in oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) were monitored by near-infrared spectroscopy for 3 hours of reperfusion. Intrarenal perfusion was evaluated separately by barium sulfate angiography. Reperfusion resulted in rapid increases in HbO2 within 1 minute in both groups. Group 1 HbO2 fell sharply to a minimum at 3 minutes but recovered by 20 minutes; group 2 changes were similar, but there was no recovery (P<0.05 by 10 minutes). Hb increased rapidly in both groups upon reperfusion but in group 2 was significantly greater after 10 minutes (P<0.05). Total hemoglobin levels were similar in both groups. Renal hemoglobin saturation was 69% at 1 minute in both groups; there was no significant change in group 1 but a profound desaturation in group 2 to 25% at 10 minute (P<0.005) and no recovery thereafter. Barium sulfate distribution was normal in all group 1 kidneys; cortical distribution was normal in all group 2 kidneys, but medullary perfusion was poor for the first 60 minutes. Renal hemoglobin oxygenation kinetics as determined here do not correlate with the timing of mitochondrial dysfunction previously reported (Thorniley et al., Kidney International, 1994; 45: 1489). We conclude that secondary ischemia during reflow is not the only mechanism leading to acute tubular necrosis.


Asunto(s)
Hemoglobinas/metabolismo , Isquemia/metabolismo , Trasplante de Riñón/efectos adversos , Riñón/irrigación sanguínea , Oxihemoglobinas/metabolismo , Animales , Femenino , Hemodinámica , Riñón/metabolismo , Riñón/patología , Cinética , Conejos , Reperfusión
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