An Analysis of How Sleep Patterns after Duty Affect Wellness in Interns Working on 24 Hour Shifts in an Emergency Medical Center: A Pilot Study

Kim, Do Hyun; Kim, Jung Youn; Yoon, Young Hoon; Kim, Su Jin; Cho, Hanjin; Choi, Sung Hyuk

Abstract

PURPOSE
We conducted a pilot study to investigate the effects of sleep patterns on wellness in interns working in the emergency department (ED). We also looked at various factors interns considered in deciding specialties and aspects of the ED they dislike, to collect the basic data necessary for quality improvement.
METHODS
We conducted a prospective observational study of interns who worked a 25 h shifts every other day by evaluating various aspects of their ellness (stress, fatigue, burnout), using questionnaires and vital signs. The questionnaires were completed four times by each subject at each shift. In total, 62 interns were assigned to teams comprised of three interns each. Each team participated in the study four times each day, once every week for 4 weeks, yielding a total of 992 questionnaires to be analyzed.
RESULTS
The participating interns were 26 years of age on average. Thirty-six (58%) were male, and twenty-six (41%) were female. Systolic and diastolic blood pressure (BP) both tended to fall as time passed, as demonstrated by relatively higher BP at 8 a.m. and 4 p.m., as compared to BP measured at 3 a.m. and 9 a.m. (systolic BP p=0.003, diastolic BP p<0.0001). Similarly, pulse rate was in the normal range at 8 a.m. and 4 p.m. but tended to fall from 3 a.m. to 9 a.m. (p<0.0001). Sleep at night-time after duty was positively correlated to the degree of stress, fatigue, and burnout, with longer night-time sleep resulting in higher scores for each. Four hours or more of daytime sleep also resulted in a statistically significant increase in stress and fatigue scores.
CONCLUSION
More than 4 hours daytime sleep after duty resulted in more stress and fatigue the next day. An increase in night-time sleep as well as total sleeping hours positively correlated with and resulted in increased stress, fatigue, and burnout scores.