Night Shift and Decreased Brain Activity of ICU Nurses: A Near-Infrared Spectroscopy Study

Area of Science:

• Neuroscience
• Occupational Health
• Sleep Medicine

Background:

• Night shift work disrupts circadian rhythms and normal physiology.
• Sleep deprivation negatively impacts brain function and cognitive abilities.
• Shift work is prevalent in healthcare, particularly affecting intensive care unit (ICU) nurses.

Purpose of the Study:

• To investigate the impact of night shifts on cognitive performance.
• To assess changes in cerebral oxygenation and hemodynamics during night shifts.
• To evaluate alterations in prefrontal cortex activity in ICU nurses.

Main Methods:

• A randomized, cross-over study involving 74 ICU nurses in Spain.
• Measured sociodemographic data, burnout, and anxiety levels.
• Assessed cerebral oxygenation using near-infrared spectroscopy and cognitive performance via a verbal fluency task.

Main Results:

• Significant decrease in regional saturation index (cerebral oxygenation) during night shifts (p < 0.001).
• Nurses exhibited significantly reduced performance on the verbal fluency test (p < 0.001).
• A significant increase in anxiety scores was observed after the night shift (p = 0.001).

Conclusions:

• Sleep deprivation during night shifts is linked to reduced dorsolateral prefrontal cortex (PFC) reactivity.
• Night shifts lead to decreased prefrontal cortex activity and impaired cognitive function in nurses.
• Findings highlight the neurocognitive consequences of night shift work in healthcare professionals.