Sleepiness and Fatigue among Night-shift with Three-hour Nap and Day Shift Nurses

Among shift work nurses, sleep deficiency results in sleepiness, fatigue, health and safety problem and also it can deteriorate the quality of care provision. The present study aimed to compare sleepiness and fatigue among night-shift nurses with three- hour nap to day-shift nurses.
A prospective cohort study was done on 23 night-shift nurses with three-hour nap and 24 day-shift nurses in Sina Hospital in Tehran (Iran) during 2015-2016. Subjective sleepiness and fatigue before and after shift were measured by Stanford Sleepiness Scale (SSS) and Swedish Occupational Fatigue Inventory (SOFI-20) respectively. Statistical analysis including independent t-test, Mann Whitney test, multivariate analysis of variance and discriminant analysis were performed to compare two groups.
Difference means of subjective sleepiness before and after shift was significantly greater among night-shift with three-hour nap (1.43±1.50) than day-shift nurses (0.37±0.92) (P-value=0.007). Although After shift, night-shift nurses(1.40±2.30) were more fatigued than day-shift ones (0.96±1.46),this was not statistically significant(P- value=0.81).Also by considering interrelationship between sleepiness and fatigue in multivariate analysis, day or night shift working with three-hour nap was an effective factor (P-value= 0.015). Discriminant analysis revealed the dominant role of subjective sleepiness to differentiate two groups.
In spite of three-hour nap, subjective sleepiness was seen more among night-shift than day-shift nurses. But mean differences scores of fatigue were not different between two groups. It seems taking three-hour nap during night shift on the one hand and heavy work load of day-shift nurses on the other hand might end in insignificant fatigue between groups. Further studies with new strategies for napping among nurses are recommended.