Working hours restriction (80-hour workweeks and 28-hour shifts) resulted in reduced sympathetic modulation and increased parasympathetic modulation during the two days following on-call duty.
Observational (n=18)
Does an on-call duty cycle under working hours restriction affect cardiac autonomic modulation in resident physicians?
Working hour restrictions for medical residents allow for autonomic recovery, characterized by increased parasympathetic and decreased sympathetic modulation in the two days following on-call duty.
Background: Medical residency is a time of high stress and long working hours, which increase the risk of cardiovascular disease. This study aimed to investigate the autonomic modulation of resident physicians throughout the on-call duty cycle. Methods: Spectral analysis of heart rate variability (HRV) was used to compute cardiac parasympathetic modulation (high-frequency power, HF) and cardiac sympathetic modulation (normalized low-frequency power, LF%, and the ratio of LF and HF, LF/HF) of 18 residents for a consecutive 4-day cycle. Results: Male residents show reduced cardiac sympathetic modulation (i.e., higher LF/HF and LF%) than the female interns. Medical residents’ cardiac parasympathetic modulation (i.e., HF) significantly increased on the first and the second post-call day compared with the pre-call day. In contrast, LF% was significantly decreased on the first and the second post-call day compared with the pre-call day. Similarly, LF/HF was significantly decreased on the second post-call day compared with the pre-call day. LF/HF significantly decreased on the first post-call day and on the second post-call day from on-call duty. Conclusion: The guideline that limits workweeks to 80 h and shifts to 28 h resulted in reduced sympathetic modulation and increased parasympathetic modulation during the two days following on-call duty.
Chien et al. (Mon,) conducted a observational in Medical residency stress (n=18). On-call duty cycle under working hours restriction vs. Pre-call day was evaluated on Cardiac parasympathetic modulation (HF) and sympathetic modulation (LF%, LF/HF). Working hours restriction (80-hour workweeks and 28-hour shifts) resulted in reduced sympathetic modulation and increased parasympathetic modulation during the two days following on-call duty.