Berit Reinmüller ny docent i Installationsteknik/Skyddsventilation vid Chalmers 2010

Dr Berit Reinmüller has been appointed the degree of docent at the Department for Energy and Environment, Division Building Services Engineering at Chalmers University of Technology.

The scientific examination was completed with a lecture October the 29th at Chalmers. Chairman of the ceremony was professor Lennart Vamling, Dean of Energy and Environment. Berit will be a distinguished member of the research group for safety ventilation at the Division for Building Services Engineering, Chalmers with liability for microbial contamination and clothing systems.

The title of the lecture was "Reduction of airborne microbial contamination in operating rooms – A reborn research area”. Berit clarified that there are three traditional methods of reducing post-operative infections: antibiotic prophylaxis, mechanical ventilation and clothing systems. The technical methods will have an increased importance due to the raised frequency of antibiotic resistant bacteria. Special care has to be taken during operations considered susceptible to infections such as hip-joint, implants and thorax operations.

In the 70-ies, Charnley showed in a study of approx 5800 hip-joint operations - performed without antibiotic prophylaxis – that the infection rate could be reduced from 7 to 1.5 percent with improved air supply systems. To go from 1.5 to 0.5 percent infection rate, special clothing systems were needed. Most current air supply systems of operating rooms have their base in Charnley’s research. Due to the interest of energy savings the air supply systems of today have lower air volume flows than those systems from the 70-ies and 80-ies.

The importance of the second technical method – clothing systems – has been elucidated with results from laboratory tests and from ongoing operations. Laboratory tests have shown that the number of washing cycles affects the filtration efficiency of the clothing system. The results from ongoing surgery show that the filtration efficiency is better for polyester materials than those of mixed materials (cotton/polyester). The results from ongoing surgeries discussed here are mainly from studies made in co-operation with Building Services Engineering, Chalmers University of Technology.

To achieve a low concentration of airborne microbial contaminants for operations considered susceptible to infections (≤10 CFU/ m3) during surgery, several combinations of air supply systems and clothing systems are possible, i.e., high quality clothing systems could be combined with air supply systems with low air flows.