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INTRODUCTION: Lung volume reduction surgery (LVRS) and endobronchial valve (EBV) placement can produce substantial benefits in appropriately selected people with emphysema. The UK Lung Volume Reduction (UKLVR) registry is a national multicentre observational study set up to support quality standards and assess outcomes from LVR procedures at specialist centres across the UK. METHODS: Data were analysed for all patients undergoing an LVR procedure (LVRS/EBV) who were recruited into the study at participating centres between January 2017 and June 2022, including; disease severity and risk assessment, compliance with guidelines for selection, procedural complications and survival to February 2023. RESULTS: Data on 541 patients from 14 participating centres were analysed. Baseline disease severity was similar in patients who had surgery n=244 (44.9%), or EBV placement n=219 (40.9%), for example, forced expiratory volume in 1 s (FEV1) 32.1 (12.1)% vs 31.2 (11.6)%. 89% of cases had discussion at a multidisciplinary meeting recorded. Median (IQR) length of stay postprocedure for LVRS and EBVs was 12 (13) vs 4 (4) days(p=0.01). Increasing age, male gender and lower FEV1%predicted were associated with mortality risk, but survival did not differ between the two procedures, with 50 (10.8%) deaths during follow-up in the LVRS group vs 45 (9.7%) following EBVs (adjusted HR 1.10 (95% CI 0.72 to 1.67) p=0.661) CONCLUSION: Based on data entered in the UKLVR registry, LVRS and EBV procedures for emphysema are being performed in people with similar disease severity and long-term survival is similar in both groups.
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Enfisema , Enfisema Pulmonar , Humanos , Masculino , Pulmón/cirugía , Neumonectomía/efectos adversos , Neumonectomía/métodos , Enfisema Pulmonar/cirugía , Sistema de Registros , Reino Unido , FemeninoRESUMEN
Chronic obstructive pulmonary disease is a condition commonly present in older people undergoing surgery and confers an increased risk of postoperative complications and mortality. Although predominantly a respiratory disease, it frequently has extra-pulmonary manifestations and typically occurs in the context of other long-term conditions. Patients experience a range of symptoms that affect their quality of life, functional ability and clinical outcomes. In this review, we discuss the evidence for techniques to optimise the care of people with chronic obstructive pulmonary disease in the peri-operative period, and address potential new interventions to improve outcomes. The article centres on pulmonary rehabilitation, widely available for the treatment of stable chronic obstructive pulmonary disease, but less often used in a peri-operative setting. Current evidence is largely at high risk of bias, however. Before surgery it is important to ensure that what have been called the 'five fundamentals' of chronic obstructive pulmonary disease treatment are achieved: smoking cessation; pulmonary rehabilitation; vaccination; self-management; and identification and optimisation of co-morbidities. Pharmacological treatment should also be optimised, and some patients may benefit from lung volume reduction surgery. Psychological and behavioural factors are important, but are currently poorly understood in the peri-operative period. Considerations of the risk and benefits of delaying surgery to ensure the recommended measures are delivered depends on patient characteristics and the nature and urgency of the planned intervention.
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Cuidados Preoperatorios , Enfermedad Pulmonar Obstructiva Crónica/patología , Antiinflamatorios/uso terapéutico , Comorbilidad , Humanos , Pulmón/fisiopatología , Apoyo Nutricional , Enfermedad Pulmonar Obstructiva Crónica/psicología , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Factores de Riesgo , Cese del Hábito de FumarRESUMEN
AIMS: In breathless individuals with respiratory disease, pulmonary rehabilitation (PR) can improve exercise capacity, symptoms and ability to cope with their condition. However, access is often limited, and adherence can be poor. Thus, there is interest in developing alternative and complementary forms of exercise intervention and tai chi may be effective in this context. METHOD: The British Lung Foundation worked in collaboration with 'Tai Chi Movements for Wellbeing' Training to train leaders to run community-based tai chi groups in the UK. Leaders received funding to run 3 months of once-a-week classes consisting of a 12 movement sequence of tai chi. Participants completed a questionnaire survey to evaluate the service at the start of their first session and again after 3 months. RESULTS: Ten tai chi groups recruited 128 participants, 65% women, mean (standard deviation (SD)) age 70.1 (7.4) years at baseline. Seventy individuals completed the follow-up questionnaire at 3 months. Participants demonstrated an improvement in Medical Research Council (MRC) Dyspnoea Score pre 3 (interquartile range (IQR) = 1.8), post 2 (IQR = 1), p = .013 and disease burden; chronic obstructive pulmonary disease (COPD) assessment test score pre 19.4 (8.7), post 17.9 (9.4), mean change -1.5 (confidence interval (CI): -2.89 to -0.127), p = .033. Those who completed the programme had a worse baseline COPD assessment test (CAT) score and were more likely to have participated in maintenance exercise previously. Qualitative feedback suggested that participants felt the classes had helped with breathlessness and relaxation. CONCLUSION: Establishing a tai chi for wellbeing programme for people with respiratory disease is feasible, with a reasonable level of compliance, and is perceived to be helpful by participants.
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Disnea/terapia , Taichi Chuan/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Enfermedades Pulmonares/terapia , Masculino , Persona de Mediana Edad , Proyectos Piloto , Enfermedad Pulmonar Obstructiva Crónica/terapia , Calidad de VidaRESUMEN
AIMS: Singing for Lung Health (SLH) is a novel intervention for individuals with respiratory disease. Qualitative results suggest benefits to physical, mental and emotional health. Limited data also suggest objective improvements in measures of quality of life with SLH are achievable. It is not known how effective the SLH groups supported by the British Lung Foundation (BLF) in the UK are. The objective was to understand the clinical impact SLH has on individuals with respiratory disease. METHODS: The BLF conducted a questionnaire survey of singers with respiratory disease from new SLH groups set up in 2016-2017. Questionnaires were administered prior to participants' first session and after 12 weeks of singing. Health-related quality of life, patient activation, anxiety and breathlessness outcomes were included. Healthcare resource utilisation including general practitioner (GP) visits, hospitalisations and frequency of inhaler use were recorded. RESULTS: A total of 228 singers participated from 26 SLH groups in the UK. Participants were 70.7 (10.1) years old, 156 (68.4%) were female and 114 (47.5%) had chronic obstructive pulmonary disease (COPD). In all, 113 (49.5%) participants provided 12-week data. There were significant improvements in COPD Assessment Test (CAT) score (Mean = -1.4, CI: (-0.25 to -2.48) ( p = .017)). Furthermore, 45% of singers reported reduced GP visits ( p ≤ .001) and 18% reported reduced hospital admissions ( p = .01). However, there were no significant improvements in general quality of life, anxiety, patient activation, breathlessness or inhaler use. Baseline characteristics were not significantly different between people who completed the 12-week evaluation and those who did not. CONCLUSIONS: This service evaluation found that participants in SLH groups report improvement in respiratory health-related quality of life and a reduction in healthcare utilisation. SLH has potential economic and health benefits. Therefore, to confirm these findings, these endpoints should be evaluated further in large-scale randomised controlled trials (RCTs).
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Calidad de Vida/psicología , Enfermedades Respiratorias/psicología , Canto , Anciano , Anciano de 80 o más Años , Organizaciones de Beneficencia , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Programas y Proyectos de Salud , Enfermedades Respiratorias/epidemiología , Encuestas y Cuestionarios , Reino Unido/epidemiologíaRESUMEN
RATIONALE: Reduced physical activity (PA) in patients with COPD is associated with a poor prognosis. Increasing PA is a key therapeutic target, but thus far few strategies have been found effective in this patient group. OBJECTIVES: To investigate the effectiveness of a 12-week semiautomated telecoaching intervention on PA in patients with COPD in a multicentre European randomised controlled trial. METHODS: 343 patients from six centres, encompassing a wide spectrum of disease severity, were randomly allocated to either a usual care group (UCG) or a telecoaching intervention group (IG) between June and December 2014. This 12-week intervention included an exercise booklet and a step counter providing feedback both directly and via a dedicated smartphone application. The latter provided an individualised daily activity goal (steps) revised weekly and text messages as well as allowing occasional telephone contacts with investigators. PA was measured using accelerometry during 1â week preceding randomisation and during week 12. Secondary outcomes included exercise capacity and health status. Analyses were based on modified intention to treat. MAIN RESULTS: Both groups were comparable at baseline in terms of factors influencing PA. At 12â weeks, the intervention yielded a between-group difference of mean, 95% CI (lower limit - upper limit; ll-ul) +1469, 95% CI (971 to 1965) steps/day and +10.4, 95% CI (6.1 to 14.7) min/day moderate PA; favouring the IG (all p≤0.001). The change in 6-min walk distance was significantly different (13.4, 95% CI (3.40 to 23.5) m, p<0.01), favouring the IG. In IG patients, an improvement could be observed in the functional state domain of the clinical COPD questionnaire (p=0.03) compared with UCG. Other health status outcomes did not differ. CONCLUSIONS: The amount and intensity of PA can be significantly increased in patients with COPD using a 12-week semiautomated telecoaching intervention including a step counter and an application installed on a smartphone. TRIAL REGISTRATION NUMBER: NCT02158065.
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Terapia por Ejercicio/métodos , Ejercicio Físico/fisiología , Enfermedad Pulmonar Obstructiva Crónica/rehabilitación , Telemedicina , Anciano , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Países Bajos , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Espirometría , Suiza , Resultado del Tratamiento , Reino UnidoRESUMEN
BACKGROUND: Klotho is an 'anti-ageing' hormone and transmembrane protein; Klotho deficient mice develop a similar ageing phenotype to smokers including emphysema and muscle wasting. The objective of this study was to evaluate skeletal muscle and circulating Klotho protein in smokers and COPD patients and to relate Klotho levels to relevant skeletal muscle parameters. We sought to validate our findings by undertaking complimentary murine studies. METHODS: Fat free mass, quadriceps strength and spirometry were measured in 87 participants (61 COPD, 13 'healthy smokers' and 13 never smoking controls) in whom serum and quadriceps Klotho protein levels were also measured. Immunohistochemistry was performed to demonstrate the location of Klotho protein in human skeletal muscle and in mouse skeletal muscle in which regeneration was occurring following injury induced by electroporation. In a separate study, gastrocnemius Klotho protein was measured in mice exposed to 77 weeks of smoke or sham air. RESULTS: Quadriceps Klotho levels were lower in those currently smoking (p = 0.01), irrespective of spirometry, but were not lower in patients with COPD. A regression analysis identified current smoking status as the only independent variable associated with human quadriceps Klotho levels, an observation supported by the finding that smoke exposed mice had lower gastrocnemius Klotho levels than sham exposed mice (p = 0.005). Quadriceps Klotho levels related to local oxidative stress but were paradoxically higher in patients with established muscle wasting or weakness; the unexpected relationship with low fat free mass was the only independent association. Within locomotor muscle, Klotho localized to the plasma membrane and to centralized nuclei in humans and in mice with induced muscle damage. Serum Klotho had an independent association with quadriceps strength but did not relate to quadriceps Klotho levels or to spirometric parameters. CONCLUSIONS: Klotho is expressed in skeletal muscle and levels are reduced by smoking. Despite this, quadriceps Klotho protein expression in those with established disease appears complex as levels were paradoxically elevated in COPD patients with established muscle wasting. Whilst serum Klotho levels were not reduced in smokers or COPD patients and were not associated with quadriceps Klotho protein, they did relate to quadriceps strength.
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Glucuronidasa/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Fumar/metabolismo , Animales , Femenino , Glucuronidasa/sangre , Humanos , Inmunohistoquímica , Proteínas Klotho , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Músculo Cuádriceps/metabolismo , Músculo Cuádriceps/fisiopatología , Análisis de Regresión , Fumar/efectos adversos , Fumar/sangre , EspirometríaRESUMEN
INTRODUCTION: Patients with COPD commonly exhibit pursed-lip breathing during exercise, a strategy that, by increasing intrinsic positive end-expiratory pressure, may optimise lung mechanics and exercise tolerance. A similar role for laryngeal narrowing in modulating exercise airways resistance and the respiratory cycle volume-time course is postulated, yet remains unstudied in COPD. The aim of this study was to assess the characteristics of laryngeal narrowing and its role in exercise intolerance and dynamic hyperinflation in COPD. METHODS: We studied 19 patients (n=8 mild-moderate; n=11 severe COPD) and healthy age and sex matched controls (n=11). Baseline physiological characteristics and clinical status were assessed prior to an incremental maximal cardiopulmonary exercise test with continuous laryngoscopy. Laryngeal narrowing measures were calculated at the glottic and supra-glottic aperture at rest and peak exercise. RESULTS: At rest, expiratory laryngeal narrowing was pronounced at the glottic level in patients and related to FEV1 in the whole cohort (r=-0.71, p<0.001) and patients alone (r=-0.53, p=0.018). During exercise, glottic narrowing was inversely related to peak ventilation in all subjects (r=-0.55, p=0.0015) and patients (r=-0.71, p<0.001) and peak exercise tidal volume (r=-0.58, p=0.0062 and r=-0.55, p=0.0076, respectively). Exercise glottic narrowing was also inversely related to peak oxygen uptake (% predicted) in all subjects (r=-0.65, p<0.001) and patients considered alone (r=-0.58, p=0.014). Exercise inspiratory duty cycle was related to exercise glottic narrowing for all subjects (r=-0.69, p<0.001) and patients (r=-0.62, p<0.001). CONCLUSIONS: Dynamic laryngeal narrowing during expiration is prevalent in patients with COPD and is related to disease severity, respiratory duty cycle and exercise capacity.
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Espiración/fisiología , Glotis/fisiopatología , Inhalación/fisiología , Respiración de Presión Positiva Intrínseca/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Resistencia de las Vías Respiratorias , Estudios de Casos y Controles , Prueba de Esfuerzo , Tolerancia al Ejercicio , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Ventilación Pulmonar , Volumen de Ventilación PulmonarRESUMEN
Although lung volume reduction surgery improves survival in selected patients with emphysema, there has been ongoing interest in developing and evaluating bronchoscopic approaches to try to reduce lung volumes with less morbidity and mortality. The placement of endobronchial valves is one such technique, and although some patients have had a significant improvement, responses have been inconsistent because collateral ventilation prevents lobar atelectasis. We describe the protocol of a trial (ISRCTN04761234) aimed to show that a responder phenotype, patients with heterogeneous emphysema and intact interlobar fissures on CT scanning, can be identified prospectively, leading to a consistent benefit in clinical practice.
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Bronquios/cirugía , Prótesis e Implantes , Implantación de Prótesis , Enfisema Pulmonar/cirugía , Proyectos de Investigación , Broncoscopía , Método Doble Ciego , Volumen Espiratorio Forzado , Humanos , Mediciones del Volumen Pulmonar , Prótesis e Implantes/efectos adversos , Enfisema Pulmonar/fisiopatologíaRESUMEN
OBJECTIVE: To evaluate the effect of a combined hospital plus home exercise programme following curative surgery for non-small cell lung cancer (NSCLC). DESIGN: Randomised controlled trial. SETTING: Teaching hospital. PARTICIPANTS: One hundred and thirty-one subjects with NSCLC admitted for curative surgery. INTERVENTIONS: Participants were randomised to usual care or a hospital plus home exercise programme. OUTCOMES: The primary outcome was the between-group difference in physical activity 4 weeks after surgery. Secondary outcomes were the difference in quadriceps strength, exercise tolerance and quality of life [Short Form-36 (SF-36) and European Organisation for Research and Treatment of Cancer (EORTC) QLQ-LC13] from pre-operatively (baseline) to 4 weeks after surgery. RESULTS: The participants (n=131) had a mean age of 68 [standard deviation (SD) 11] years and mean forced expiratory volume in 1 second of 2.4 (SD 1.1)l. There were no significant differences in physical activity between the groups 4 weeks after surgery [mean difference adjusted for baseline 12minutes/day, 95% confidence interval (CI) -20.2 to 44.1]. In addition, there were no significant differences in total SF-36 or EORTC QLQ-LC13 scores from baseline to 4 weeks after surgery. Both groups had recovered their pre-operative walking distance 4 weeks after surgery, and there were no differences between the groups (mean difference in Incremental Shuttle Walk Test from baseline to 4 weeks after surgery (-26m, 95% CI -94.2 to 42.3). CONCLUSIONS: A hospital plus home exercise programme showed little benefit in unselected patients with NSCLC following surgery. Regardless of group allocation, the patients had recovered their pre-operative exercise tolerance levels by 4 weeks after surgery.
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Carcinoma de Pulmón de Células no Pequeñas/rehabilitación , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Terapia por Ejercicio/métodos , Neoplasias Pulmonares/rehabilitación , Neoplasias Pulmonares/cirugía , Anciano , Tolerancia al Ejercicio , Femenino , Hospitales de Enseñanza , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular , Calidad de VidaRESUMEN
Bronchoscopic therapies to reduce lung volumes in chronic obstructive pulmonary disease are intended to avoid the risks associated with lung volume reduction surgery (LVRS) or to be used in patient groups in whom LVRS is not appropriate. Bronchoscopic lung volume reduction (BLVR) using endobronchial valves to target unilateral lobar occlusion can improve lung function and exercise capacity in patients with emphysema. The benefit is most pronounced in, though not confined to, patients where lobar atelectasis has occurred. Few data exist on their long-term outcome. 19 patients (16 males; mean±sd forced expiratory volume in 1 s 28.4±11.9% predicted) underwent BLVR between July 2002 and February 2004. Radiological atelectasis was observed in five patients. Survival data was available for all patients up to February 2010. None of the patients in whom atelectasis occurred died during follow-up, whereas eight out of 14 in the nonatelectasis group died (Chi-squared p=0.026). There was no significant difference between the groups at baseline in lung function, quality of life, exacerbation rate, exercise capacity (shuttle walk test or cycle ergometry) or computed tomography appearances, although body mass index was significantly higher in the atelectasis group (21.6±2.9 versus 28.4±2.9 kg·m(-2); p<0.001). The data in the present study suggest that atelectasis following BLVR is associated with a survival benefit that is not explained by baseline differences.
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Broncoscopía , Neumonectomía , Atelectasia Pulmonar/mortalidad , Atelectasia Pulmonar/cirugía , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/cirugía , Índice de Masa Corporal , Prueba de Esfuerzo , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/fisiología , Masculino , Persona de Mediana Edad , Resistencia Física/fisiología , Atelectasia Pulmonar/diagnóstico por imagen , Atelectasia Pulmonar/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/mortalidad , Enfisema Pulmonar/fisiopatología , Enfisema Pulmonar/cirugía , Calidad de Vida , Radiografía , Resultado del TratamientoAsunto(s)
Medicina Aeroespacial/métodos , Hipoxia/complicaciones , Síndrome de QT Prolongado/etiología , Trastornos Respiratorios/complicaciones , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Electrocardiografía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Quadriceps strength relates to exercise capacity and prognosis in chronic obstructive pulmonary disease (COPD). We wanted to quantify the prevalence of quadriceps weakness in COPD and hypothesised that it would not be restricted to patients with severe airflow obstruction or dyspnoea. Predicted quadriceps strength was calculated using a regression equation (incorporating age, sex, height and fat-free mass), based on measurements from 212 healthy subjects. The prevalence of weakness (defined as observed values 1.645 standardised residuals below predicted) was related to Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage and Medical Research Council (MRC) dyspnoea score in two cohorts of stable COPD outpatients recruited from the UK (n = 240) and the Netherlands (n = 351). 32% and 33% of UK and Dutch COPD patients had quadriceps weakness. A significant proportion of patients in GOLD stages 1 and 2, or with an MRC dyspnoea score of 1 or 2, had quadriceps weakness (28 and 26%, respectively). These values rose to 38% in GOLD stage 4, and 43% in patients with an MRC Score of 4 or 5. Quadriceps weakness was demonstrable in one-third of COPD patients attending hospital respiratory outpatient services. Quadriceps weakness exists in the absence of severe airflow obstruction or breathlessness.
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Disnea/fisiopatología , Debilidad Muscular/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Músculo Cuádriceps/fisiopatología , Índice de Severidad de la Enfermedad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Tolerancia al Ejercicio/fisiología , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Persona de Mediana Edad , Debilidad Muscular/etiología , Países Bajos , Prevalencia , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Estudios Retrospectivos , Reino UnidoRESUMEN
Quadriceps muscle weakness is an important component of chronic obstructive pulmonary disease (COPD). We hypothesised that quadriceps weakness would also be a feature of restrictive lung disease due to scoliosis. We studied 10 patients with severe scoliosis (median (interquartile range (IQR)) forced expiratory volume in 1 s (FEV(1))() 35.3 (11)% predicted), 10 patients with severe COPD (FEV(1) 26.5 (9.0)% pred) and 10 healthy age-matched adults. We measured quadriceps strength, exercise capacity and analysed quadriceps muscle biopsies for myosin heavy-chain (MyHC) isoform expression and the presence of oxidative stress. Both groups exhibited quadriceps weakness with median (IQR) maximal voluntary contraction force being 46.0 (17.0) kg, 21.5 (21.0) kg and 31.5 (11.0) kg, respectively (p = 0.02 and 0.04, respectively, for each patient group against controls). Oxidative stress was significantly greater in the quadriceps of both restrictive and COPD patients. The scoliosis patients exhibited a decrease in the proportion of MyHC type I compared with controls; median (IQR) 35.3 (18.5)% compared with 47.7 (9.3)%, p = 0.028. The scoliosis patients also showed an increase in MyHC IIx (26.3 (15.5)% compared with 11.3 (13.0)%, p = 0.01. Quadriceps weakness is a feature of severe scoliosis; the similarities between patients with scoliosis and patients with COPD suggest a common aetiology to quadriceps weakness in both conditions.
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Debilidad Muscular/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Músculo Cuádriceps/patología , Escoliosis/complicaciones , Escoliosis/fisiopatología , Anciano , Biopsia , Estudios de Casos y Controles , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular , Músculos/patología , Cadenas Pesadas de Miosina/químicaRESUMEN
Assessment of quadriceps endurance is of interest to investigators studying human disease. We hypothesized that repetitive magnetic stimulation (rMS) of the intramuscular branches of the femoral nerve could be used to induce and quantify quadriceps endurance. To test this hypothesis, we used a novel stimulating coil to compare the quadriceps endurance properties in eight normal humans and, to confirm that the technique could be used in clinical practice, in eight patients with advanced chronic obstructive pulmonary disease (COPD). To validate the method, we compared in vivo contractile properties of the quadriceps muscle with the fiber-type composition and oxidative enzyme capacity. We used a Magstim Rapid(2) magnetic nerve stimulator with the coil wrapped around the quadriceps. Stimuli were given at 30 Hz, a duty cycle of 0.4 (2 s on, 3 s off), and for 50 trains. Force generation and the surface electromyogram were measured throughout. Quadriceps twitch force, elicited by supramaximal magnetic stimulation of the femoral nerve, was measured before and after the protocol. Quadriceps muscle biopsies were analyzed for oxidative (citrate synthase, CS) and glycolytic (phosphofructokinase, PFK) enzyme activity and myosin heavy chain isoform protein expression. The time for force to fall to 70% of baseline (T(70)) was shorter in the COPD group than the control group: 55.6 +/- 26.0 vs. 121 +/- 38.7 s (P = 0.0014). Considering patients and controls together, positive correlations were observed between T(70) and the proportion of type I fibers (r = 0.68, P = 0.004) and CS-to-PFK ratio (CS/PFK) (r = 0.67, P = 0.005). We conclude that quadriceps endurance assessed using rMS is feasible in clinical studies.
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Magnetismo , Fatiga Muscular/fisiología , Fuerza Muscular/fisiología , Tono Muscular/fisiología , Músculo Cuádriceps/fisiología , Anciano , Biopsia , Ejercicio Físico/fisiología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Músculo Cuádriceps/patología , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Quadriceps muscle weakness is common in chronic obstructive pulmonary disease (COPD) but is not observed in a small hand muscle (adductor pollicis). Although this could be explained by reduced activity in the quadriceps, the observation could also be explained by anatomical location of the muscle or fibre type composition. However, the abdominal muscles are of a similar anatomical and fibre type distribution to the quadriceps, although they remain active in COPD. Cough gastric pressure is a recently described technique that assesses abdominal muscle (and hence expiratory muscle) strength more accurately than traditional techniques. A study was undertaken to test the hypothesis that more severe weakness exists in the quadriceps than in the abdominal muscles of patients with COPD compared with healthy elderly controls. METHODS: Maximum cough gastric pressure and quadriceps isometric strength were measured in 43 patients with stable COPD and 25 healthy elderly volunteers matched for anthropometric variables. RESULTS: Despite a significant reduction in mean quadriceps strength (29.9 kg v 41.2 kg; 95% CI -17.9 to -4.6; p = 0.001), cough gastric pressure was preserved in patients with COPD (227.3 cm H(2)O v 204.8 cm H(2)O; 95% CI -5.4 to 50.6; p = 0.11). CONCLUSIONS: Abdominal muscle strength is preserved in stable COPD outpatients in the presence of quadriceps weakness. This suggests that anatomical location and fibre type cannot explain quadriceps weakness in COPD. By inference, we conclude that disuse and consequent deconditioning are important factors in the development of quadriceps muscle weakness in COPD patients, or that activity protects the abdominal muscles from possible systemic myopathic processes.
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Músculo Esquelético/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Músculos Abdominales/fisiopatología , Anciano , Tos/fisiopatología , Femenino , Humanos , Contracción Isométrica/fisiología , Masculino , Presión , Músculos Respiratorios/fisiopatologíaRESUMEN
BACKGROUND: Nocturnal non-invasive ventilation (NIV) is an effective treatment for hypercapnic respiratory failure in patients with restrictive thoracic disease. We hypothesised that NIV may reverse respiratory failure by increasing the ventilatory response to carbon dioxide, reducing inspiratory muscle fatigue, or enhancing pulmonary mechanics. METHODS: Twenty patients with restrictive disease were studied at baseline (D0) and at 5-8 days (D5) and 3 months (3M). RESULTS: Mean (SD) daytime arterial carbon dioxide tension (Paco(2)) was reduced from 7.1 (0.9) kPa to 6.6 (0.8) kPa at D5 and 6.3 (0.9) kPa at 3M (p = 0.004), with the mean (SD) hypercapnic ventilatory response increasing from 2.8 (2.3) l/min/kPa to 3.6 (2.4) l/min/kPa at D5 and 4.3 (3.3) l/min/kPa at 3M (p = 0.044). No increase was observed in measures of inspiratory muscle strength including twitch transdiaphragmatic pressure, nor in lung function or respiratory system compliance. CONCLUSIONS: These findings suggest that increased ventilatory response to carbon dioxide is the principal mechanism underlying the long term improvement in gas exchange following NIV in patients with restrictive thoracic disease. Increases in respiratory muscle strength (sniff oesophageal pressure and sniff nasal pressure) correlated with reductions in the Epworth sleepiness score, possibly indicating an increase in the ability of patients to activate inspiratory muscles rather than an improvement in contractility.
Asunto(s)
Respiración Artificial/métodos , Insuficiencia Respiratoria/terapia , Enfermedades Torácicas/terapia , Dióxido de Carbono/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Debilidad Muscular/terapia , Pruebas de Función Respiratoria , Insuficiencia Respiratoria/fisiopatología , Músculos Respiratorios/fisiología , Enfermedades Torácicas/fisiopatología , Resultado del TratamientoRESUMEN
Prospective data to support the hypothesis that corticosteroids are a significant cause of muscle weakness in patients with chronic obstructive pulmonary disease (COPD) are lacking. The authors studied respiratory and quadriceps muscle function, using both volitional techniques and magnetic nerve stimulation, as well as measuring metabolic parameters during incremental cycle ergometry, in 25 stable COPD patients. The forced expiratory volume in one second was 37.6 +/- 21.4% predicted, before and after a 2-week course of o.d. prednisolone 30 mg. Quadriceps strength was also assessed in 15 control patients on two occasions. Only two patients met the British Thoracic Society definition of steroid responsiveness. There was no change either in sniff transdiaphragmatic pressure (pre: 96.8 +/- 19.7 cmH2O; post: 98.6 +/- 22.4 cmH2O) or in twitch transdiaphragmatic pressure elicited by bilateral anterolateral magnetic phrenic-nerve stimulation (pre: 16.8 +/- 9.1 cmH2O; post: 17.9 +/- 10 cmH2O). Quadriceps twitch force did not change significantly either in the steroid group (pre: 9.5 +/- 3.1 kg; post: 8.9 +/- 3.7 kg) or in the control patients (pre: 8.1 +/- 2.7 kg; post: 7.9 +/- 2.2 kg). There were no changes in either peak or isotime ventilatory and metabolic parameters during exercise. In conclusion, in stable patients with chronic obstructive pulmonary disease, a 2-week course of 30 mg prednisolone daily does not cause significant skeletal muscle dysfunction or alter metabolic parameters during exercise.
Asunto(s)
Corticoesteroides/efectos adversos , Debilidad Muscular/inducido químicamente , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Músculos Respiratorios/efectos de los fármacos , Corticoesteroides/uso terapéutico , Anciano , Estudios de Casos y Controles , Prueba de Esfuerzo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Debilidad Muscular/fisiopatología , Músculo Esquelético/efectos de los fármacos , Fenómenos Fisiológicos Musculoesqueléticos/efectos de los fármacos , Probabilidad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Valores de Referencia , Pruebas de Función Respiratoria , Músculos Respiratorios/fisiología , Medición de Riesgo , Índice de Severidad de la Enfermedad , Reino UnidoRESUMEN
We report a case of histologically confirmed Scedosporium prolificans pulmonary infection secondary to long-standing bronchiectasis that necessitated excision lung surgery. This case emphasizes the difficulties with the medical management of deep-seated fungal infections.