Shiftwork

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Shiftwork

• Models of Shiftwork and Health An Examination of
  the Influence of Stress on Shiftwork Theory.
  Taylor, Briner and Folkard (1997).
• Air Traffic Controller Shiftwork What are the
  Implications for Aviantion Safety? A Review.
  Luna (1997).
• Effect of Forward Rapidly Rotating Shiftwork on
  Circadian Rhythms of Arterial Pressure, Heart
  Rate and Oral Temperature in Air Traffic
  Controllers. Stoynev and Minkova (1998).

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Taylor et al.

• Discussed
• History and association
• Four models of health and shift work
• Stress theorys impact on shift work
• Recommendation for the future study

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Taylor et al.

• Introduction to Shiftwork
• Definition and importance
• How Circadian rhythms are affected
• Do people really adjust?

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Taylor et al.

• Risks associated with Shiftwork
• Deficits in sleep
• Disruption to family/social life
• Health problems
• Accidents

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Taylor et al.

• Health Impacts
• Not really understood
• Dependent on personality factors
• Morningness
• Flexibility
• Vigor

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Taylor et al.

• Rutenfranzs model (1976)
• One of the first models
• Involves Objective stress, subjective stress,
  intervening variables.
• Most linear
• Shiftwork is just plain bad

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Taylor et al.

• Haider et al Model (1981)
• More dynamic than Rutenfranz
• Equilibrium is the goal
• Functioning of domains
• Risky habits
• Incorporated cognition and behavior
• Included interrelatedness of problems

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Taylor et al.

• Monk Model (1988)
• Coping is key
• Three factors to cope with
• Biological clock (circadian rhythm)
• Sleep factors
• Social/domestic factors

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Taylor et al.

• Olsson et al Model (1990)
• Most detailed, dynamic
• Based on Lazarus and Folkmans (1984) model of
  stress
• Shiftwork only a part of the whole
• Coping is the cognitive and behavioral efforts to
  handle stress.

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Taylor et al
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Taylor et al.

• Stress Theory
• From stimulus-based to dynamic transaction
• Shiftwork theory has followed stress theory
• How useful is that though?

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Taylor et al.

• Lack of clarity in stress research
• Engels 1985 article, Stress is a Noun. No, a
  Verb! No, an Adjective!
• Is stress a stimulus, a response, or a
  transaction?
• Is stress research worth it?

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Taylor et al.

• Benefits and Costs of Stress Theory for Shiftwork
  theory
• Pros
• Recognition of new variables
• Theoretical diversification
• Cons
• Poor theory clarity
• Limited ability to falsify

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Taylor et al.

• Interventions
• Responsibility
• Organizations
• Employees
• Lack of systematic evaluation

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Taylor et al.

• Recommendations
• Greater awareness of stress research
• Just like in Stress literature
• Development of theory
• Refine theory
• Narrow theory

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Luna

• Discussed
• Background
• Shift schedules
• Impact on sleep and performance
• What can be done?

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Luna

• Background
• Circadian Rhythm and body temp
• Synchronization
• Nocturnal rhythm
• Zeitgebers (time givers)
• Natural, habitual, and social cues
• Bright light most powerful

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Luna

• Rapid rotation shifts
• Social benefits and prevalence
• Desynchronosis
• Advancing/Backward
• Delaying/Forward

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Luna

• Sleep
• Detriment of lost sleep
• Chronic vs acute sleep debt
• Objective vs subjective measures
• Air traffic controllers
• Stress and sleep
• Workload problems
• Sleep inertia and sleep paralysis

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Luna

• Performance
• Circadian rhythms
• Day oriented
• Night work
• Chernobyl, Three Mile Island, etc.
• ATC performance
• ATC error rates
• Light workloads

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Luna

• Interventions
• Slower and permanent rotation schedules
• Increasing workload
• Bright light and napping
• Others

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Luna

• Conclusion
• Rapid Rotation seems the best
• Problems
• Circadian Rhythm
• Desynchronosis
• Workloads
• Not enough info on countermeasures

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Stoynev and Minkova

• Discussed
• The effect of rapid rotation shift work on
  circadian rhythms
• Purpose and method of study
• Results and Discussion

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Stoynev and Minkova

• Introduction
• Air traffic controllers
• How good are forward rapid rotation shifts?
• Subjects
• Male ATCs on a 5-day RRS

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Stoynev and Minkova

• Methods
• Measurement of
• Systolic, diastolic and mean arterial pressure
• heart rate
• Oral temperature
• Physical task
• Mental task
• Masking

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Stoynev and Minkova

• Results and Discussion
• Lack of a reversal of the circadian rhythms
• Circadian rhythms
• Desynchronization
• Forward RRS are good (maybe)

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