Dynamic Ventilatory Reserve During Incremental Exercise: Reference Values and Clinical Validation in Chronic Obstructive Pulmonary Disease.

Rationale: Ventilatory demand-capacity imbalance, as inferred based on a low ventilatory reserve, is currently assessed only at peak cardiopulmonary exercise testing (CPET). Peak ventilatory reserve, however, is poorly sensitive to the submaximal, dynamic mechanical ventilatory abnormalities that are key to dyspnea genesis and exercise intolerance. Objectives: After establishing sex- and age-corrected norms for dynamic ventilatory reserve at progressively higher work rates, we compared peak and dynamic ventilatory reserve for their ability to expose increased exertional dyspnea and poor exercise tolerance in mild to very severe chronic obstructive pulmonary disease (COPD). Methods: We analyzed resting functional and incremental CPET data from 275 controls (130 men, aged 19-85 yr) and 359 Global Initiative for Chronic Obstructive Lung Disease patients with stage 1-4 obstruction (203 men) who were prospectively recruited for previous ethically approved studies in three research centers. In addition to peak and dynamic ventilatory reserve (1 - [ventilation / estimated maximal voluntary ventilation] × 100), operating lung volumes and dyspnea scores (0-10 on the Borg scale) were obtained. Results: Dynamic ventilatory reserve was asymmetrically distributed in controls; thus, we calculated its centile distribution at every 20 W. The lower limit of normal (lower than the fifth centile) was consistently lower in women and older subjects. Peak and dynamic ventilatory reserve disagreed significantly in indicating an abnormally low test result in patients: whereas approximately 50% of those with a normal peak ventilatory reserve showed a reduced dynamic ventilatory reserve, the opposite was found in approximately 15% (P < 0.001). Irrespective of peak ventilatory reserve and COPD severity, patients who had a dynamic ventilatory reserve below the lower limit of normal at an isowork rate of 40 W had greater ventilatory requirements, prompting earlier attainment of critically low inspiratory reserve. Consequently, they reported higher dyspnea scores, showing poorer exercise tolerance compared with those with preserved dynamic ventilatory reserve. Conversely, patients with preserved dynamic ventilatory reserve but reduced peak ventilatory reserve reported the lowest dyspnea scores, showing the best exercise tolerance. Conclusions: Reduced submaximal dynamic ventilatory reserve, even in the setting of preserved peak ventilatory reserve, is a powerful predictor of exertional dyspnea and exercise intolerance in COPD. This new parameter of ventilatory demand-capacity mismatch may enhance the yield of clinical CPET in the investigation of activity-related breathlessness in individual patients with COPD and other prevalent cardiopulmonary diseases.

Lipodistrofia congénita generalizada tipo 2 en la cultura moche / Generalized congenital lipodystrophy type 2 in the moche culture

RESUMEN Los artistas moches (50 y 850 años d. C.) son unos de los mayores representantes plásticos en los andes centrales durante la época prehispánica, dentro de este escenario fue posible el análisis de una pieza de cerámica registrada en el sitio arqueológico Huaca de la Luna, ubicada en Trujillo. La vasija corresponde a dos individuos con características morfológicas que permite asociarlos con el padecimiento de lipodistrofia congénita generalizada tipo 2. Considerando la zona geográfica, los rasgos físicos y los casos actuales de esta enfermedad nos permite indicar que en la sociedad Mochica probablemente existieron personas con lipodistrofia congénita generalizada.

ABSTRACT The Moche artist are among the most outstanding plastic representatives in the central Andes during the pre-Hispanic era, within this scenario, we could analyze a sculptural ceramic piece (code C-1335) recorded in the Huaca de la Luna archaeological site in Trujillo, Perú. The vessel corresponds to two individuals with morphological characteristics that allow them to be associated with type 2 congenital generalized lipodystrophy. Considering the geographical, the physical features, and the current cases of this disease, allow us to indicate that people with generalized congenital lipodystrophy probably existed in Mochica society during pre-Hispanic times.