Patients with severe respiratory or lung conditions need to receive extensive care, and their lung function must be continuously monitored. Fraunhofer researchers have developed a textile vest with built-in acoustic sensors as part of the Pneumo.Vest project to record lung noises.
Software is then used to transform the signals and display them graphically. This means that patients outside of intensive care units can still be continuously monitored. The patient’s quality of life is enhanced by this technology, which expands the range of possible diagnoses.
The stethoscope has been a common medical instrument for more than 200 years and is a representation of the medical industry. Doctors are frequently depicted sprinting through the hallways while wearing a stethoscope in hospital dramas on television. Skilled medical professionals utilize them to listen to the heartbeat and the lungs very precisely and, as a response, identify ailments.
The stethoscope is now receiving some assistance. Researchers from the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Berlin have created a textile vest with built-in acoustic sensors as part of the Pneumo.Vest project, which offers a high-performance alternative to the conventional stethoscope.
The front and rear of the vest are equipped with piezoceramic acoustic sensors that can detect any sound made by the lungs in the thorax, no matter how minute. The lungs are visibly represented on a monitor as the signals are recorded and electrically amplified.
The software can pinpoint the location of the data since it is aware of the exact location of each individual sensor. This generates a precise auditory and optical image of the ventilation state of each lung segment.
What makes it so unique is that examinations are possible at any time and without hospital staff because the system permanently captures and retains the data. Pneumo.Vest also provides information on the condition of the lungs across time, such as during the preceding 24 hours. Naturally, classical auscultation can also be done on patients directly.
Thus, a range of sensors are employed simultaneously rather than manually doing auscultation at various sites with just a stethoscope.
Pneumo.Vest is not looking to make the stethoscope redundant and does not replace the skills of experienced pneumologists. However, auscultation or even CT scans of the lungs only ever present a snapshot at the time of the examination.
Ralf Schallert, Project Manager, Fraunhofer IKTS
“Our technology provides added value because it allows for the lungs to be monitored continuously in the same way as a long-term ECG, even if the patient is not attached to machines in the ICU but has instead been admitted to the general ward,” explains Schallert.
Machine Learning Algorithms Aid With Diagnosis
The software is at the heart of the vest, along with the acoustic sensors. It is in charge of handling the data’s storage, representation, and analysis. The doctor can utilize it to view the acoustic events in particular individual lung regions on the display. A focused assessment of acoustic signals is made possible by the application of algorithms in digital signal processing. This implies that it is feasible, for instance, to increase or filter out specific frequency ranges, which makes it much easier to notice lung sounds like rustling or wheezing.
In addition, the researchers at Fraunhofer IKTS are developing machine-learning techniques. These will eventually be able to organize and categorize complicated ambient noises in the thorax. The pneumologist will then take the closing assessment and diagnosis.
Discharge from the ICU
The digital sensor substitute can also help patients. When using the vest, patients can heal without needing ongoing medical supervision. They can move around freely, shift to the general ward, and perhaps even be discharged home. Despite this, the lungs are constantly observed, and any rapid decline can be immediately reported to medical staff.
The idea works in practice, according to the results of the initial trials with employees at the University Clinic for Anesthesiology and Intensive Therapy at the University of Magdeburg.
“The feedback from doctors was overwhelmingly positive. The combination of acoustic sensors, visualization, and machine learning algorithms will be able to reliably distinguish a range of different lung sounds,” explains Schallert.
The technology has impressed Dr. Alexander Uhrig from Charité - Universitätsmedizin Berlin as well. One of the individuals who came up with the concept was the infectiology and pneumology expert at the renowned Charité hospital, stating, “Pneumo.Vest addresses exactly what we need. It serves as an instrument that expands our diagnostic options, relieves the burden on our hospital staff, and makes hospital stays more pleasant for patients.”
Although the technology was initially intended for respiratory patients, it is also effective when used in sleep research centers and by residents of care homes. Additionally, it can be used to teach medical students auscultation.
Increased Need for Clinical-Grade Wearables
Fraunhofer IKTS scientists created the Pneumo.Vest as a solution to the deteriorating conditions in hospitals. Every year, 385,000 individuals in Germany with respiratory or pulmonary disorders need inpatient care.
More than 60% of patients use a ventilator for longer than 24 hours. The recent surge in respiratory patients brought on by the COVID-19 pandemic is not taken into account in this number.
The medical community anticipates a rise in the number of elderly individuals with breathing issues because of rising life expectancy. The pressure on hospitals, and particularly expensive ICUs, can be lessened with the use of technology from Fraunhofer IKTS because their beds will not be occupied for as long.
The market for such clinical-grade wearables is expanding quickly. To detect vital signs like a heartbeat, blood oxygen saturation, breathing rate, or skin temperature, these small medical gadgets can be worn directly on the body. Pneumo.Vest, a flexible medical gadget, fits in perfectly with this advancement.