Abstract: The aim of this researcher is design a system of mixed lighting for intensive care unit in the city of Cartagena. The lighting design was performed according to the recommendations of the technical regulations lighting and public lighting, Resolution No. 180540 of March 30, 2010 issued by the Ministry of Mines and Energy. The proposed redesign allows medical personnel per form various tasks with different lighting requirements and reduce eye strain, preventing impairment of visual acuity in health workers and improve working conditions. Concluded that the new lighting system will improve lighting, reduce errors and accidents and increase patient safety. By employing natural and artificial lighting also improves circadian cycle in workers with strenuous working hours e positively influences mood and patient recovery.