Relative cardiac cost and physical, mental and psychological work load among a group of post-operative care personnel.

Continuous registration of heart rate and careful minute-by-minute observation of all physical, mental and psychological job-related events was carried out in a group of nine post-operative care personnel. The relative cardiac cost (RCC) correlated significantly with the observed work events. The magnitude of participation of physical, mental and psychological work elements in the changes in RCC varied in the investigated subjects according to the type and magnitude of the different work events. However, collective data on the group indicated that changes in RCC were related mainly to physical effort and to a lesser, albeit significant, extent to psychological reaction. The results indicate the possibility of using the heart rate in monitoring working conditions and, probably, in guiding their improvement.