Bringing model based ventilation therapy to the bedside

Modern approaches to respiratory therapy based on computer modeling ought to keep up with the latest technologies. In the era of tablet PCs and smartphones, lung diagnoses and therapy optimization could be brought to patients right at their bedside. To this end, previously presented simulations of patient physiology [1] were redesigned to run on mobile devices. Moreover, a socket communication over WiFi was established between a desktop computer and a tablet PC so that data read from the ventilator (Evita XL that is connected to the computer) can be transferred to the tablet. In order to run the application on an Android operating system, the previously developed MATLAB code must be rewritten in Java. A Graphical User Interface (GUI) was designed so that one can choose any combination of a ventilation mode (Volume Control, Pressure Control, SIMV or BiP AP), a combination of submodels describing lung mechanics, gas exchange and cardiovascular dynamics. Moreover, simulation can be adapted to individual patients by selecting lung diseases (chronic obstructive pulmonary disease or adult respiratory distress syndrome), as well as enter parameters for those selections. Outputs of interest such as airway pressure or flow can be reviewed after running the simulation thanks to an android library called androidplot. The presented software is constantly improved and extended to further implement additional ventilation modes and patient models. These initial tests show that mobile devices can easily be integrated into today´s medical decision support. More sophisticated and less efficient calculations can be performed on servers running in parallel to the handheld system. The mathematical models of human respiratory system [1] and the simulation model for patient ventilator interaction [2] were successfully implemented in mobile devices.