Newly Published
Education  |   May 2019
Anesthesiology Resident Night Float Duty Alters Sleep Patterns: An Observational Study
Author Notes
  • From the Department of Anesthesiology (L.K.D., A.M.K., K.T.F., A.J.B., S.R.C., J.F.P., C.J.K., J.L.H., E.C.N.) and the Department of Neurosurgery (E.C.N.), University of Virginia, Charlottesville, Virginia; and the Department of Nutrition and Exercise Physiology, Washington State University, Spokane, Washington (S.T.).
  • Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).
    Supplemental Digital Content is available for this article. Direct URL citations appear in the printed text and are available in both the HTML and PDF versions of this article. Links to the digital files are provided in the HTML text of this article on the Journal’s Web site (www.anesthesiology.org).×
  • The work presented in this article has been presented at the International Anesthesia Research Society Annual Meeting in Chicago, Illinois, April 29, 2018.
    The work presented in this article has been presented at the International Anesthesia Research Society Annual Meeting in Chicago, Illinois, April 29, 2018.×
  • Submitted for publication September 18, 2018. Accepted for publication April 15, 2019.
    Submitted for publication September 18, 2018. Accepted for publication April 15, 2019.×
  • Correspondence: Address correspondence to Dr. Dunn: University of Virginia Health System, P.O. Box 800710, Charlottesville, Virginia 22908. lak3r@virginia.edu. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Article Information
Education / Central and Peripheral Nervous Systems / Education / CPD / Sleep Medicine
Education   |   May 2019
Anesthesiology Resident Night Float Duty Alters Sleep Patterns: An Observational Study
Anesthesiology Newly Published on May 28, 2019. doi:10.1097/ALN.0000000000002806
Anesthesiology Newly Published on May 28, 2019. doi:10.1097/ALN.0000000000002806
Abstract

Editor’s Perspective:

What We Already Know about This Topic:

  • Night float is one mechanism for fulfilling resident call responsibilities while avoiding prolonged clinical care that violates duty hours

What This Article Tells Us That Is New:

  • In anesthesiology residents conducting six consecutive nights of clinical care, three nights of recovery did not appear to restore normal sleep architecture, raising questions about this practice

Background: Residency programs utilize night float systems to adhere to duty hour restrictions; however, the influence of night float on resident sleep has not been described. The study aim was to determine the influence of night float on resident sleep patterns and quality of sleep. We hypothesized that total sleep time decreases during night float, increases as residents acclimate to night shift work, and returns to baseline during recovery.

Methods: This was a single-center observational study of 30 anesthesia residents scheduled to complete six consecutive night float shifts. Electroencephalography sleep patterns were recorded during baseline (three nights), night float (six nights), and recovery (three nights) using the ZMachine Insight monitor (General Sleep Corporation, USA). Total sleep time; light, deep, and rapid eye movement sleep; sleep efficiency; latency to persistent sleep; and wake after sleep onset were observed.

Results: Mean total sleep time ± SD was 5.9 ± 1.9 h (3.0 ± 1.2.1 h light; 1.4 ± 0.6 h deep; 1.6 ± 0.7 h rapid eye movement) at baseline. During night float, mean total sleep time was 4.5 ± 1.8 h (1.4-hour decrease, 95% CI: 0.9 to 1.9, Cohen’s d = –1.1, P < 0.001) with decreases in light (2.2 ± 1.1 h, 0.7-hour decrease, 95% CI: 0.4 to 1.1, d = –1.0, P < 0.001), deep (1.1 ± 0.7 h, 0.3-hour decrease, 95% CI: 0.1 to 0.4, d = –0.5, P = 0.005), and rapid eye movement sleep (1.2 ± 0.6 h, 0.4-hour decrease, 95% CI: 0.3 to 0.6, d = –0.9, P < 0.001). Mean total sleep time during recovery was 5.4 ± 2.2 h, which did not differ significantly from baseline; however, deep (1.0 ± 0.6 h, 0.4-hour decrease, 95% CI: 0.2 to 0.6, d = –0.6, P = 0.001 *, P = 0.001) and rapid eye movement sleep (1.2 ± 0.8 h, 0.4-hour decrease, 95% CI: 0.2 to 0.6, d = –0.9, P < 0.001 P < 0.001) were significantly decreased.

Conclusions: Electroencephalography monitoring demonstrates that sleep quantity is decreased during six consecutive night float shifts. A 3-day period of recovery is insufficient for restorative sleep (rapid eye movement and deep sleep) levels to return to baseline.