It is reasonable to combine all these aspects (parameters) when titrating PEEP. The weights of different parameters are worth examining. Another drawback selleck chem of the present study is that only patients with healthy lungs were recruited in the study. After this feasibility study, a further investigation on ALI/ARDS patients is essential. PEEP selection based on GI index or lung mechanics analysis may exhibit a different relation in patients suffering from severe respiratory insufficiency.ConclusionsIn the present study, we found that a PEEP level, at which the lung was most homogenously ventilated, always existed during a standardized incremental PEEP trial. Such PEEP level is optimal with respect to ventilatory homogeneity and can be identified using the GI index.
Moreover, the GI index may provide new insights into the relation between lung mechanics and tidal volume distribution. In further clinical evaluations it may be used to guide ventilator settings in combination with other aspects such as gas exchange and lung mechanics.Key messages? The PEEP selection is a process depending on the individual properties of a patient and his or her disease state. Different aspects, such as blood gas, respiratory system mechanics and ventilatory homogeneity, need to be considered at the bedside.? Evaluation of EIT data allows the incorporation of the patient’s state of respiratory homogeneity into therapeutical decision-making at the bedside.? It is feasible and reasonable to titrate the PEEP level with respect to ventilatory homogeneity based on EIT.? Lung mechanics and tidal volume distribution are related.
However, the relation may vary among different lung diseases.AbbreviationsARDS: acute respiratory distress syndrome; ASA: american society of anesthesiology classification; CT: computed tomography; DI: the value of the differential impedance in the tidal images; DIlung : all pixels in the lung area under observation; DIxy : the pixel in the identified lung area; EIT: electrical impedance tomography; GI: global inhomogeneity; PaO2 : partial pressure of arterial oxygen; PEEP: positive end-expiratory pressure; P/V: pressure-volume curve; SD: standard deviation; ZEEP: zero end-expiratory pressure.Competing interestsThe authors declare that they have no competing interests.Authors’ contributionsZZ designed the study, analyzed the data and drafted the manuscript.
DS carried out the data measurement. IF revised the manuscript critically. JG gave valuable advices and contributed to writing. KM contributed to GSK-3 study design, data analysis and writing. All authors read and approved the final manuscript.NotesSee related commentary by Costa and Amato, http://ccforum.com/content/14/2/134AcknowledgementsThis work was supported by Bundesministerium f��r Bildung und Forschung (Grant 1781X08 MOTiF-A), and Dr?ger Medical, L��beck.