Scheduled napping as a countermeasure to sleepiness in air traffic controllers

Abstract

SUMMAR Y The aims of this study were to measure sleep during a planned nap on the night shift;and to use objective measures of performance and alertness to compare the effects of the nap opportunity versus staying awake. Twenty-eight air traffic controllers (mean age 36 years, nine women) completed four night shifts (two with early starts and two with late starts). Each type of night shift (early ⁄ late start) included a 40-min planned nap opportunity on one occasion and no nap on the other. Polysomnographic data were used to measure sleep and waking alertness [spectral power in the electroencephalogram (EEG) during the last hour of the night shift and the occurrence of slow rolling eye movements (SEMs) subsequent to the nap]. Psychomotor performance task [Psychomotor Vigilance Task (PVT)] was completed at the beginning and end of the shift, and after the nap (or an equivalent time if no nap was taken). Nap sleep latencies were relatively long (mean = 19 min) and total sleep time short (mean = 18 min), with minimal slow wave sleep (SWS, mean = 0%), and no rapid eye movement sleep. Nap sleep resulted in improved PVT performance (mean and slowest 10% of reaction time events), decreased spectral power in the EEG and reduced the likelihood of SEMs. The occurrence of SWS in the nap decreased spectral power in the EEG. This study indicates that although sleep taken at work is likely to be short and of poor quality it still results in an improvement in objective measures of alertness and performance.k e y w o r d s air traffic control, naps, neurophysiological alertness, night shift, psychomotor performance, within-subjects field study

Effects of Napping During Shift Work on Sleepiness and Performance in Emergency Medical Services Personnel and Similar Shift Workers: A Systematic Review and Meta-Analysis

“…The impact of scheduled naps on personnel performance was judged favorable for eight of 11 studies that measured personnel performance (Table 2) (25)(26)(27)(28)(29)(30)(31)(32). Two studies were judged as no impact and one as mixed/ inconclusive for personnel performance.…”

“…Two studies were judged as no impact and one as mixed/ inconclusive for personnel performance. Pooled analysis was performed for three experimental studies that measured reaction time at the start and end of shift (27,29,31 (27). The effect of naps on reaction time measured at the end of shift was small, and the difference between the nap and no-nap condition was non-significant (SMD 0.12, 95% CI −0.13 to 0.36; p = 0.34; Figure 2a).…”

“…Eleven studies evaluated the impact of napping on measures of acute fatigue (25,(27)(28)(29)(31)(32)(33)(34)(35)(36)(37). The impact of napping on acute fatigue (sleepiness) was judged favorable for five of 11 studies, mixed/inconclusive for three studies, and no impact for three studies ( Table 2).…”

“…The use of data from the 1st shift was appropriate as the participants would be more naïve to the intervention compared to the participants in the 2nd shift. Signal and colleagues generated reaction time with use of the 10-minute psychomotor vigilance test (PVT) (31). Raw means and SDs were not reported in the manuscript.…”

“…Raw means and SDs were not reported in the manuscript. These data were obtained from Signal upon request specific to the "early night shift" start of shift and end of shift PVT measures (31). Data for reaction time (means and SDs) for the Sallinen et al study were abstracted from Table 2 of the manuscript specific to the early 30 arm (27).…”