Mental illnesses such as depression, burnout or post-traumatic stress disorder are widespread problems in nursing care and often cause long-term sickness. Particularly in intensive care units, the burden and the associated risk are psychologically high. This work has the aim to find preventive measures and to check them for their effectiveness. In the theoretical section, reference is made to the service sequence of an intensive care unit and the associated stress factors. Three different mental illnesses are briefly defined and described. The main part of this work is then concerned with measures and interventions that have already been investigated, which should enable nurses to be maintained in intensive care units against the above mentioned mental illnesses. Different methods were compared and analyzed for their effectiveness regarding to study results.