Every year, around 420,000 people in Germany become infected with the often particularly resistant "hospital germs", of which the antibiotic-resistant Staphylococcus aureus is the best known, but not the only one. These infections lead to longer hospital stays, higher costs and, in an estimated 7,500 cases in Germany alone, death every year.
In intensive care units, artificial respiration most frequently leads to such infections. The patient is given a ventilation tube (endotracheal tube) which remains in the windpipe for days. During this time, pathogens can multiply on the inside or outside of the tube, migrate into the lungs and cause infections there.
This problem was addressed in the "self-disinfecting LED endotracheal tubes (LED-ETT)" project funded by the German Federal Ministry of Education and Research (BMBF) and carried out by Professor Hessling's working group at the Institute of Medical Technology and Mechatronics at Ulm University of Applied Sciences. Medical technology student Ben Sicks investigated how bacterial pathogens can be reduced or killed with blue LEDs - i.e. with visible light that is harmless to human cells - before they enter the lungs.
To this end, he integrated 48 1.6 mm miniature LEDs into a standard ventilation tube. In the test setup, the blue-illuminated tube irradiated a bacterial test solution with a homogeneous irradiation intensity and achieved a 99.9 % reduction in bacterial concentration within 6-9 hours. The microbial tests thus significantly inhibited the growth of bacteria on the endotracheal tube.
This promising approach has now been honored with the Applied Photonics Award, which is presented annually by the Fraunhofer Institute for Applied Optics and Precision Engineering in Jena.
Ben Sicks' further research will focus on keeping the ventilation tube not only free of bacteria but also viruses, which is particularly important in times of Covid-19.
Source: THU
