Introduction
Intensive care units are the units that provide uninterrupted health services for the treatment of critically ill patients. Although the indications for hospitalization in intensive care units include departmental and diagnostic differences, the criticality of the patient’s condition is considered a general-accepted reason for hospitalization. The general international rule is that qualified and certified healthcare professionals should work in intensive care units. In this regard, our country and many other countries provide in-service trainings and try to increase the number of qualified health personnel.
Mortality rates in intensive care units are higher than in other clinics. Studies have found different mortality rates, ranging from 8 to 30%1–3. Common causes of mortality include respiratory diseases, coronary heart diseases, infectious causes, and cerebrovascular diseases1,4. There are studies reporting higher rates of mortality in intensive care units in the night-shift and at the weekend shifts compared to the weekday day-shift5–8. In these studies, the leading causes of mortality included insufficient number of healthcare professionals, difficult access to invasive procedures, and the presence of cases with high mortality rates, etc.
There are studies in the literature reporting that the level of attention decreases in night shifts. In a study, Yıldız et al9revealed lower scores of the visual attention test for women working in the night-shift compared to those working in the day-shift. In another study, Osterode et al. found a decrease in cognitive functions in the night-shift in the visual memory test applied to physicians.
In health care services in our country, the night-shift usually starts from the end of the day-shift at 16.00 and continues until the beginning of the day-shift at 08.00. In case of insufficient number of healthcare professionals, the duration of the shift can be extended up to 24 hours. For healthcare professionals working in the Intensive Care Units at the Gazi Yaşargil Training and Research Hospital, which is the center of our research, the night-shift covers sixteen hours from 16.00 to 08.00 on the next day. The day shift group was selected from nurses working in the day shift for the past month. Thus, it was aimed to exclude the possibility of shift-related deterioration in sleep rhythm and hormonal balance in day-shift workers.