Less stress in the OP from noise reduction?

Joint research by psychologists and physicians at the University of Göttingen


The syringe pump beeps, the aspirator and heart–lung machine noisily perform their work. A healthcare professional rips open a package of additional materials necessary for further sterilisation.

The noise levels in the OP sum up to average levels of over 70 decibels SPL (sound pressure level). These levels were measured by chief physician Dr. Martin Friedrich and his team. The complex processes of open-heart surgery require advanced technology medical equipment. They produce noise that accumulates to such an enormous level. ”We have had peak levels of over 100 decibels and on average in the OP it is louder than the Göttingen motorway exit “, says Dr. Friedrich. We can prove this with long-term measurements.

He consequently developed a system that actively and passively combats the noise in the OP: the Silent Operating Theatre Optimisation System or SOTOS.

”When we used SOTOS for the first time during a heart operation, it seemed much quieter and less stressful than before“, reported Priv.-Doz. Dr. Sebastian Russo from the Centre of Anaesthesiology (AINS). ”And whether this subjective impression also enacts an objective stress relief and positive impact on OP staff and our patients is something we intend to investigate scientifically.“

Therefore physicians and psychologists are working together to investigate what impact SOTOS compared to conventional operating conditions has on the staff members’ stress experiences and cognitive performance. ”In addition we will look at how the team-experience and communication processes change under the influence of the system“, explains Prof. Dr. Margarete Boos. She is head of the Department of Social and Communication Psychology at the University of Göttingen, Germany.

The long-term interest of the Göttingen physicians and psychologists is whether this noise reduction technology also supports the well-being of patients. They will investigate this on the basis of postsurgical effects. ”We want to find out how the noise reduction affects our staff members as well as the patients“, said Dr. Friedrich.

Swiss psychologists Julia Seelandt, Franziska Tschan and Norbert Semmer have already shown in their research that noise during operations can be harmful to patients (Tschan et al., 2015; Seelandt et al., 2014). In their studies they found a correlation between noise levels in the OP and the amount of postsurgical wound infections.

“SOTOS could therefore also affect patient safety and perhaps even the medication required for general anaesthesia“, claims Dr. Martin Friedrich.