ABSTRACT
OBJECTIVE: Current standards for conducting spirometry examinations recommend that the ventilation manoeuvres needed in pulmonary function testing are carried out repeatedly during sessions. Chest electrical impedance tomography (EIT) can determine the presence of ventilation heterogeneity during such manoeuvres, which increases the information content derived from such examinations. The aim of this study was to characterise regional lung function in patients with chronic obstructive pulmonary disease (COPD) during repetitive forced full ventilation manoeuvres. Regional lung function measures derived from these manoeuvres were compared with quiet tidal breathing. APPROACH: Sixty hospitalised patients were examined during up to three repeated ventilation manoeuvres. Acceptable spirometry manoeuvres were performed and EIT recordings suitable for analysis obtained in 53 patients (12 women, 41 men; age: 68 ± 12 years (mean ± SD)). Pixel values of tidal volume, forced full inspiratory and expiratory volume in 1 s, and forced inspiratory and expiratory vital capacity were calculated from the EIT data. Spatial ventilation heterogeneity was assessed using the coefficient of variation, global inhomogeneity index, and centres and regional fractions of ventilation. Temporal inhomogeneity was determined by examining the pixel expiration times needed to exhale 50% and 75% of regional forced vital capacity. MAIN RESULTS: All EIT-derived measures of regional lung function showed reproducible results during repetitive examinations. Parameters of spatial heterogeneity obtained from quiet tidal breathing were comparable with the measures derived from the forced manoeuvres. SIGNIFICANCE: Measures of spatial and temporal ventilation heterogeneity obtained in COPD patients by EIT provide comparable findings during repeated examinations within one testing session. Quiet tidal breathing generates similar information on ventilation heterogeneity as forced manoeuvres that demand a high amount of patient effort.
Subject(s)
Pulmonary Disease, Chronic Obstructive , Tomography , Aged , Electric Impedance , Female , Humans , Lung/diagnostic imaging , Male , Pulmonary Ventilation , Respiratory Function TestsABSTRACT
In intensive care medicine, rapid technical developments that are often beneficial to patients are taking place. On the other hand, there are also voices that generally criticize an increasing "interventionalism". This area of tension includes other important questions regarding usefulness, quality, ethical compliance, scientific evidence, structural capacities and economy. The treatment of acute respiratory distress syndrome (ARDS) using extracorporeal membrane oxygenation (ECMO) is an example of these considerations. Although ECMO has rarely been prospectively evaluated according to scientific criteria, it is still used with an increasing tendency, not least since the documented register survival rates in ECMO patients with severe ARDS are 60%. However, the implementation of this therapy means an immense effort. The necessary centralization and certification for ECMO treatment is currently under intensive discussion. Closely related to this are considerations about which criteria represent good quality in patient care. In order to be able to guarantee high quality, a precise indication is the first step. And here indications and contraindications still need to be defined. It has not yet been sufficiently clarified which prognosis factors need to be taken into account. This article summarizes what is known about ECMO prognosis and indication criteria. In conclusion, parameters are identified that should be developed scientifically in the future.
Subject(s)
Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Contraindications , Critical Care , Humans , Prognosis , Respiratory Distress Syndrome/therapyABSTRACT
Eosinophilia presents a challenge to differential diagnostics due to the multitude of possible causes. An initial difficulty is often to distinguish between threatening disease symptoms and relatively harmless secondary reactions. A highly dynamic clinical progression with severe impairment of the vital functions, like breathing, for example, can make swift action necessary. An example of this is known as acute eosinophile pneumonia, which can often only be controlled with the rapid use of high steroid doses. However, a peripheral blood eosinophilia must not lead to an automatic use of steroids before the most important core tests, as this can compromise further diagnostic measures. Furthermore, less dramatic courses require careful handling of an eosinophilia. Various pneumological, infectological, rheumatological or haematological / oncological disease patterns with a prolonged course can develop seriously if they are not recognised in time and treated in a targeted manner. There is no guideline for eosinophile clinical pictures in general. Already the recommendations for a structured diagnosis are scarce and are often concentrated on internist emphases.
