The coronavirus outbreak has demonstrated clearly how vital they are: ventilators are often the treatment of last resort. The continuous adaptation of this complex technology to the individual needs of patients has been the focus of research in Medical Informatics and Biomedical Engineering at Furtwangen University for the last 15 years.
"One aspect of our research on ventilation treatment is to create 'digital twins', in other words to develop models that replicate patient characteristics," explains Prof. Dr. Knut Möller, Head of the Institute for Applied Research. "The progression of a severe lung disease is different in each person requiring personalised ventilation. Individualised models can be used to evaluate different therapeutic approaches prior to use." The goal is to develop devices that adapt autonomously to the changing needs of the patients. This would also simplify the daily routines of clinical staff. "The doctors decide on the treatment strategy. With technology that constantly adapts to patients’ needs, the negative side effects of ventilation could be minimised," Möller says.
Ventilation is an extremely tricky treatment to administer. If parts of the lung close, pressure must be applied to expand these areas again. However, at the same time this pressure must not overstretch the tissue of the functioning parts. But how can ventilation distribution in a lung be monitored during breathing? To ensure that air distribution and oxygen intake can be accurately tracked, Möller and his team at Furtwangen University are also working with modern sensor technology and image reconstruction algorithms for ventilation monitoring. Belts worn around the chest can measure gas distribution in the thorax using small electric currents. In the pictures of test subjects which Möller shows, coloured areas demonstrate how much of the breath is flowing in which parts of the lungs. "As far as practical applications outside ICU are concerned, it would, for example, be valuable for cystic fibrosis patients, if they could observe the immediate benefit of a physiotherapeutic treatment being administered," Möller explains.
In the current "MOVE" research project, this measurement method is combined with computer tomography images. "The quality of the images is higher making them much easier for doctors to read," says Möller commenting on the "pretty pictures we can now produce." Just one of the many challenges involved is movement during measurements. Lungs expand during breathing and the thorax rises and falls - yet the sensors must be able to provide images of all areas, at all times. "The external movements of the thorax must also be recorded, because they provide information about how strenuous breathing is for the patient," Möller explains. That is why the scientists are also testing the use of several measuring belts simultaneously to continuously improve results. And in addition to improving breathing, there is still the question of whether the oxygen from the lungs can actually be absorbed into the blood... there are innumerable sub-problems in the research field of ventilation technology. But Möller is confident – even though the regulations and test procedures for every semi- or fully-automated technology for which approval is sought are particularly strict and time consuming - the computer scientist expects that the improved ventilation systems, "like autonomous driving", will gradually come into use in the foreseeable future.