J.M. Broquetas

Metabolic characteristics of the deltoid muscle in patients with chronic obstructive pulmonary disease.

The purpose of this study was to analyse key enzyme activities of the deltoid muscle (DM) in chronic obstructive pulmonary disease (COPD) patients. The activities of one oxidative enzyme (citrate synthase (CS)), two glycolytic enzymes (lacatate dehydrogenase (LD); and phosphofructokinase (PFK)) and one enzyme related to the use of energy stores (creatine kinase (CK)) were determined in the DM of 10 patients with COPD and nine controls. Exercise capacity (cycloergometry) and the handgrip strength were also evaluated. Although exercise capacity was markedly reduced in COPD (57 +/- 20% predicted), their handgrip strength was relatively preserved (77 +/- 19% pred). The activity of LD was higher in the COPD patients (263.9 +/- 68.2 versus 184.4 +/- 46.5 mmol x min(-1) x g(-1), p<0.01), with a similar trend for CS (67.3 +/- 33.3 versus 46.0 +/- 17.4 mmol x min(-1) x g(-1), p = 0.07). Interestingly, the activity of the latter enzyme was significantly higher than controls if only severe COPD patients were considered (81.8 +/- 31.2 mmol x min(-1) x g(-1), p < 0.01). PFK and CK activities were similar for controls and COPD. Chronic obstructive patients show a preserved or even increased (severe disease) oxidative capacity in their deltoid muscle. This coexists with a greater capacity in the anaerobic part of the glycolysis. These findings are different to those previously observed in muscles of the lower limbs.

Dyspnoea at rest and at the end of different exercises in patients with near-fatal asthma

Blunted perception of dyspnoea under resistive loading has been observed in patients with a history of near-fatal asthma (NFA). The perception of dyspnoea at rest and at the end point of various exercises was assessed in such patients. Respiratory function and exercise capacity (6‐min walking distance, incremental cycloergometry and inspiratory threshold loading) were assessed in seven NFA and eight non-NFA patients. Dyspnoea (Borg scale) was measured at rest and at the end point of the various exercises. Dyspnoea at rest was significantly lower in NFA patients. Although exercise tolerance was similarly reduced in both the NFA and non-NFA groups, dyspnoea at peak cycle exercise was significantly lower in the former (2.6±2 versus 6.1±3.8 (Borg scale; mean±sd)), who mainly (86%) stopped because of leg discomfort. A similar trend was observed in the 6‐min walking distance and inspiratory threshold loading tests. Dyspnoea at peak exercise was the best indicator of the NFA condition, with a sensitivity of 100% and specificity of 63% for a Borg scale score of ≤6. Perception of dyspnoea is blunted in near-fatal asthma patients at both rest and the end point of various forms of exercise. Dyspnoea at peak exercise is the best indicator of the near-fatal asthma condition.

Cuestionario de calidad de vida en pacientes con asma: la versión española del Asthma Quality of Life Questionnaire

En este trabajo se describe la traduccion y adaptacion al castellano de un instrumento de medicion de la calidad de vida en pacientes con asma, el Asthma Quality of Life Questionnaire (AQLQ). El AQLQ, desarrollado por Juniper et al., es un cuestionario de 32 items, cinco de los cuales corresponden a actividades habituales que puede seleccionar el propio paciente de una lista de 26 posibles actividades. Las opciones de respuesta a los items se obtienen en una escala de 7 puntos. Para la adaptacion se utilizo el metodo de traduccion-retrotraduccion por personas bilingues. Se valoro la equivalencia con la version original para cada item, actividad y opcion de respuesta: totalmente equivalente (A), bastante equivalente pero con alguna expresion dudosa (B) o equivalencia dudosa ( C ). Se evaluo tambien la naturalidad y correccion de la version espanola en una escala de 1 a 10. Se consideraron 3 items (9%) y una actividad (4%) como de equivalencia dudosa (C) y 12 items (37%) y una actividad (4%) fueron considerados tipo B. Se discutieron las dudas de equivalencia (B y C) y las expresiones equivalentes, pero poco naturales o gramaticalmente incorrectas en dos reuniones: una de todos los investigadores y traductores y otra posterior con un grupo de 6 pacientes asmaticos. Se obtuvo una expresion final consensuada para cada uno de estos items y actividades que se incluyo en una segunda version. La nueva version fue administrada a otro grupo de 7 pacientes para comprobar su comprension y equivalencia. Como resultado, despues de la discusion por los investigadores, se obtuvo la version definitiva del cuestionario. Los resultados del proceso de adaptacion del AQLQ sugieren que la version espanola de este instrumento es comprensible para los pacientes y equivalente a la version original. Sus propiedades como instrumento de medida deberan ser evaluadas en posteriores estudios que determinen su validez, fiabilidad y sensibilidad a los cambios.

Características del cáncer de pulmón en un hospital universitario. Cambios epidemiológicos e histológicos en relación con una serie histórica

Objetivo: Describir las caracteristicas clinicas, histologicas y epidemiologicas de los pacientes diagnosticados de cancer de pulmon en nuestro hospital durante un periodo de 5 anos y compararlas con las de una serie historica del mismo centro. Pacientes y metodos: Se incluyo retrospectivamente a todos los pacientes diagnosticados de cancer de pulmon desde enero de 1998 hasta diciembre de 2002, y se compararon con los datos obtenidos durante el periodo comprendido entre enero de 1978 y marzo de 1981. Resultados: El total de pacientes fue de 678 y la edad media, de 67 anos. De los varones (89%), el 56% eran fumadores, y de las mujeres, el 62% eran no fumadoras (p < 0,001). Los tipos histologicos mas frecuentes fueron el carcinoma escamoso (33%) y el adenocarcinoma (30%). El carcinoma escamoso fue el mas frecuente en varones (36%) y el adenocarcinoma en mujeres (56%). En el momento del diagnostico presentaban metastasis el 42% de los pacientes con carcinoma no microcitico y el 55% de los microciticos. Las neoplasias previas mas frecuentes fueron la de laringe entre los pacientes con carcinoma escamoso y la de vejiga entre los afectados de adenocarcinoma. Al comparar con la serie historica observamos que actualmente la relacion varon:mujer es menor, la proporcion de carcinoma escamoso es inferior y la de adenocarcinoma superior (p < 0,001) y el porcentaje de pacientes diagnosticados en estadio regional es mayor (p < 0,001). Conclusiones: El tipo histologico mas frecuente sigue siendo el carcinoma escamoso. Ser varon y fumador se asocia a carcinoma escamoso, y ser mujer, a adenocarcinoma. En comparacion con la serie historica observamos cambios en las caracteristicas epidemiologicas e histologicas, posiblemente en relacion con las modificaciones en el habito tabaquico.

Structure and function relationships of the respiratory muscles

Potential relationships between the structure of the diaphragm and external intercostals and several indices of respiratory muscle function, lung function and nutrition in 27 patients (61+/-10 yrs of age) subjected to thoracotomy as a result of a lung neoplasm have been investigated. Prior to surgery the nutritional status of the patients was assessed and lung function (spirometry, lung volumes, transfer factor of the lungs for carbon monoxide, arterial blood gases) and respiratory muscle function (maximal inspiratory pressure (MIP) and diaphragmatic function were measured). Biopsies of the diaphragm (and external intercostals) were obtained during surgery. On average, patients showed mild airflow limitation (forced expiratory volume in one second (FEV1), 70+/-14% of predicted value, FEV1/forced vital capacity (FVC), 70+/-9%) with some air trapping (residual volume (RV), 139+/-50% pred) and normal gas exchange (arterial oxygen tension (Pa,O2), 11.3+/-1.33 kPa (85+/-10 mmHg)) and arterial carbon dioxide tension (Pa,CO2) 5.4+/-0.5 kPa (40.6+/-4 mmHg). MIP was 77+/-25% pred; maximal transdiaphragmatic pressure was 90+/-27 cmH2O. Most morphometric measurements of the diaphragm and external intercostals were within the range of values reported previously in other skeletal muscles. The size of the fibres of these two respiratory muscles was positively related (p<0.05) to MIP (% pred). There were no significant relationships between the structure of both muscles and nutritional status or any index of lung function. In conclusion, in the population studied, the fibre size of the diaphragm and external intercostals appears to relate to their ability to generate force.

Lung Cancer at a University Hospital: Epidemiological and Histological Characteristics of a Recent and a Historical Series

OBJECTIVE To describe the clinical, histological, and epidemiological characteristics of patients diagnosed with lung cancer in our hospital over a period of 5 years and compare them with those of historical cases treated at the same hospital. PATIENTS AND METHODS The cases of patients diagnosed with lung cancer from January 1998 through December 2002 were studied retrospectively and compared with data published for the period from 1978 through March 1981. RESULTS A total of 678 patients (89% men, mean age 67 years) were studied. Fifty-six percent of the men and 38% of the women were smokers (P<.001). The most common histological types were squamous cell carcinoma (33%) and adenocarcinoma (30%): squamous carcinoma in men (36%) and adenocarcinoma in women (56%). Metastasis was present in 42% of the patients with non-small cell lung cancer and in 55% of those with small cell lung cancer. In patients with a history of neoplastic disease, laryngeal tumors were most common in patients with squamous carcinoma whereas bladder tumors were the most frequent in patients with adenocarcinoma. The ratio of men to women was lower in the recent series than in the historical one. The percentage of squamous carcinoma was lower and that of adenocarcinoma higher (P<.001). The percentage of patients diagnosed with regional involvement was greater in the recent series (P<.001). CONCLUSIONS Squamous cell carcinoma continues to be the most frequent histological type. Male sex and smoking are associated with squamous carcinoma and female sex is associated with adenocarcinoma. Epidemiological and histological patterns have changed, possibly in relation to changes in smoking habits.

Dual morphometrical changes of the deltoid muscle in patients with COPD.

The present study was specifically aimed at evaluating if the structure of the deltoid muscles is modified in patients with chronic obstructive pulmonary disease (COPD). Twenty-eight male volunteers (61+/-13 yr) were assigned, according to pulmonary function, to either the COPD (n=14, FEV(1)=22-74%pred) or control group (n=14, FEV(1)=83-121%pred). Biopsies from non-dominant deltoid muscle were obtained and processed for morphometric analysis of the fibre types. Both type I and type II muscle fibres were distributed in the typical mosaic pattern. The mean value of the fibre size was within the normal range. However, three differentiated modes were observed in the deltoid from COPD patients: a central mode of normal sized fibres, a mode of atrophic fibres and a mode of hypertrophic fibres. This observation was evident even within single fascicles and especially prevalent in the most severe COPD patients. We conclude that factors with opposite effect (promotion of either atrophy or hypertrophy) exert relevant roles in the histomorphometrical characteristics of the deltoid muscles in COPD patients.

Síndrome de bajo peso asociado a la EPOC en nuestro medio

Introduccion La enfermedad pulmonar obstructiva cronica (EPOC) es una entidad de elevada prevalencia, con importantes consecuencias economicas y sanitarias, que derivan en gran parte de la limitacion que la enfermedad comporta en la actividad y expectativas vitales del paciente. Uno de los factores recientemente implicados en las citadas limitaciones es la presencia de bajo peso asociada con la enfermedad. Aunque la causa no esta clara, esta alteracion parece afectar a un numero importante de pacientes (entre el 25 y el 35% segun las series), al menos en el norte de Europa y los EE.UU. Sin embargo, existe la percepcion de que la situacion podria ser diferente en el area mediterranea. Objetivo Aproximar la prevalencia del sindrome de bajo peso en pacientes con EPOC de nuestro entorno. Metodo Se revisaron las caracteristicas antropometricas basicas de los pacientes con EPOC filiados funcionalmente en nuestro laboratorio a lo largo de los dos ultimos anos (2000–2001). Resultados De los 3.126 sujetos analizados, la prevalencia de un indice de masa corporal (IMC) por debajo de 20 kg/m2fue de tan solo el 6,6%, cifra que se reducia al 3,1% si el dintel escogido era el de 18 kg/m2. Este dato es aun mas llamativo si se tiene en cuenta que casi la mitad de los pacientes evidenciaban enfermedad grave (volumen espiratorio forzado en el primer segundo [FEV1] inferior al 50% ref). El IMC se correlaciono directamente con FEV1/FVC y transferencia del CO. Conclusiones Estos resultados sugieren que los pacientes con EPOC de nuestra area geografica presentan caracteristicas fenotipicas diferenciadas de las previamente descritas en otras latitudes. En concreto, una menor prevalencia del sindrome de bajo peso. Sin embargo, esta observacion debe ser confirmada en estudios mas amplios.

Activity of latissimus dorsi muscle during inspiratory threshold loads

The ability of the latissimus dorsi muscle (LD) to participate as an accessory inspiratory muscle has been the subject of controversy. Electromyographic (EGM) activity of LD was evaluated in 11 healthy subjects (aged 30 +/- 2 yrs; forced expiratory volume in one second (FEV1) 106 +/- 5% predicted; maximal inspiratory pressure (Pmax), 120 +/- 6 cmH2O) under different breathing conditions. The ipsilateral biceps brachii was chosen as the control muscle. The EMG was recorded from surface electrodes, but needle electrodes were also used for LD evaluation in a subset of three subjects. The EMG signal from both muscles was recorded simultaneously, rectified and integrated, with subtraction of the electrocardiographic signal. Situations evaluated were: 1) maximal voluntary contraction (MVC); 2) apnoea; and 3) breathing under progressive inspiratory threshold loads (20-100% Pmax, at 20% intervals). A close relationship was evident between LD recordings from surface and needle electrodes (r = 0.975). Activity of LD at baseline was 1.8 +/- 0.4% MVC, and showed a phasic increase during inspiration under loads. This change had a linear tendency and was significant for loads corresponding to 40, 60, 80 and 100% of Pmax when compared to the control muscle. At this latter level, LD activity was equivalent to 32 +/- 5% MVC (range 11-61%), whereas mean activity of the control muscle was less than 7.5% MVC.(ABSTRACT TRUNCATED AT 250 WORDS)

Gastro-oesophageal reflux in mechanically ventilated patients: effects of an oesophageal balloon

Gastro-oesophageal reflux (GOR) and bronchoaspiration of gastric content are risk factors linked with ventilator-associated pneumonia. This study was aimed at evaluating the effect of a nasogastric tube (NGT) incorporating a low-pressure oesophageal balloon on GOR and bronchoaspiration in patients receiving mechanical ventilation. Fourteen patients were studied in a semi-recumbent position for 2 consecutive days. Inflation or deflation of the oesophageal balloon was randomised. Samples of blood, gastric content, and oropharyngeal and bronchial secretions were taken every 2 h over a period of 8 h. A radioactively labelled nutritional solution was continuously administered through the NGT. The magnitude of both the GOR and bronchoaspiration was measured by radioactivity counting of oropharyngeal and bronchial secretion samples, respectively. Inflation of the oesophageal balloon resulted in a significant decrease of both GOR and bronchoaspiration of gastric content. This protective effect was statistically significant from 4 h following inflation throughout the duration of the study. This study demonstrates that an inflated oesophageal balloon delays and decreases gastro-oesophageal and bronchial aspiration of gastric content in patients carrying a nasogastric tube and receiving enteral nutrition during mechanical ventilation. Although the method was found to be safe when applied for 8 h, longer times should be considered with caution.