Shift Work
& the
Efficient
Emergency
Department
Shift Work and the Efficient ED
Vicken Y. Totten MD:
 Emergency Physician
 and Career-long Shift Worker

1
Shift Work
& the
Efficient
Emergency
Department
2
Shift Work
& the
Efficient
Emergency
Department
Goals and Objectives:
Offer concrete suggestions to optimize your
ED workforce by...
 Discussing the effects of poorly conceived
shift work on work performance by:
 Describe normal sleep structure
 Definitions and shift patterns

3
Shift Work
& the
Efficient
Emergency
Department
SLEEP
Sleep, that knits the ravell'd sleave of care,
 The death of each day's life, sore labour's
bath,
 Balm of hurt minds, great nature's second
course,
 Chief nourisher in life's feast.

-
4
Shakespeare, Macbeth, Act II, Scene I
Shift Work
& the
Efficient
Emergency
Department
5
Shift Work
& the
Efficient
Emergency
Department
Definitions
Chronodisruption -- the circadian rhythms
are out of synchronization with each other
and with the external world. Classic
example is jet lag.
 Sleep deprivation -- lack of core sleep
 Sleepiness -- the feeling of wishing to
sleep; drowsiness

6
Shift Work
& the
Efficient
Emergency
Department
Normal Human Circadian Cycle
Day = alert; night = sleep.
 Most physiologic systems cycle through the
24 hour “day”
 Modern life is increasingly 24/7, especially
Emergency Medicine
 Medicine is far behind industry in
recognizing the inefficiencies of shift work

7
Shift Work
& the
Efficient
Emergency
Department
Circadian rhythms
All body systems change rhythmically
 Most humans have about 25-26 hour
circadian cycle
 Other well known cycles have different
periods: 90 minute alertness cycle, fertility
monthly cycle, etc.
 Not all systems adapt to a new schedule
at same rate!

8
Shift Work
& the
Efficient
Emergency
Department
Concept of “Core Sleep”
Horne: first three SWS cycles with their
REM periods
 "optional" sleep the rest of the night: more
REM, less SWS
 Core sleep: about 5 hours for most persons
 Only core sleep made up.

9
Shift Work
& the
Efficient
Emergency
Department
Concept of Sleepiness
2 components: core versus optional
 missing core sleep (physiologic) -- disrupts
physiologic systems
 missing optional sleep (psychological) -mostly psychological / mood effects
 both feel drowsy

10
Shift Work
& the
Efficient
Emergency
Department
Sleep deprivation
loss of "optional sleep" (sleeping less than
one's habit) causes drowsiness, no other
serious effects
 "core sleep" deprivation (less than 5 hours
of slow wave sleep) -- true sleep deprivation
 Sleep deprivation causes both physiologic
and psychological ill effects

11
Shift Work
& the
Efficient
Emergency
Department
Emergency Medicine vs.
Office-based Specialties
On call -- potential for disrupted sleep or
sleep deprivation. Does not affect zeitgibers
or circadian rhythm
 On duty -- In the work environment,
performing diurnal tasks during a “day”
defined by a clock rather than by social
zeitgibers. Potential for circadian
disruption.

12
Shift Work
& the
Efficient
Emergency
Department
13
Shift Work
& the
Efficient
Emergency
Department
Normal Physiology and Sleep
Most physiologic functions follow the daily
temperature cycle
 Alertness greatest when body temperature is
at its physiologic peak, minimal when
cortizol and temperature at their nadir

14
Shift Work
& the
Efficient
Emergency
Department
15
Shift Work
& the
Efficient
Emergency
Department
At Night, the unadjusted worker:
Performance for stimulating, high-attention
tasks is unchanged
 Attention wanders for routine, nondemanding tasks
 “Daydreams” and micro-sleeps intrude
 “Code” performance ok, but subtle things
missed.

16
Shift Work
& the
Efficient
Emergency
Department
17
Shift Work
& the
Efficient
Emergency
Department
Normal Sleep Architecture:
Stages of sleep
Non-REM (NREM) sleep - Stages I-IV
brain idle, body mobile
 REM - Body paralyzed, Brain active (more
metabolically active than during waking!)

18
Shift Work
& the
Efficient
Emergency
Department
Stage 1 - transition period.
Normally 10 minutes. Eyes rove.
 Most people awakened during Stage 1 claim
they are not asleep.

19
Shift Work
& the
Efficient
Emergency
Department
Stage 2 - Deeper, fewer eye
movements.
Shallowest restorative sleep.
 About half of adult sleep in Stage 2.
 20 min. before progressing to next stage.

20
Shift Work
& the
Efficient
Emergency
Department
Stages 3/4 - Slow wave sleep
(SWS), (delta sleep)
Most restorative & restful; vital for physical
recuperation.
 Majority occurs early in the sleep period.
 Difficult to arouse from SWS.
 First stage to be “made up” after sleep
deprivation.
 SWS deprivation causes fatigue, muscle
aches and worse.

21
Shift Work
& the
Efficient
Emergency
Department
REM sleep: brain on, body off
Vital for psychological well-being;
 May be critical for learning
 Isolated REM deprivation causes irritability,
progresses to psychosis, then death
 EEG similar to wakefulness. Dreams,
irregular pulse, respiration, increased BP,
loss of muscle tone, and absent spinal
reflexes.

22
Shift Work
& the
Efficient
Emergency
Department
REM sleep
First episode occurs after 90-120 minutes of
NREM sleep.
 Recurs in about 90 minute cycles, getting
more frequent towards awakening
 REM periods become longer as night
progresses.

23
Shift Work
& the
Efficient
Emergency
Department
24
On Call versus On Duty
Shift Work
& the
Efficient
Emergency
Department
25
Shift Work
& the
Efficient
Emergency
Department
On Call
On call: night work between working days =
pure sleep deprivation
 Possibility of sleep while on call
 Main work is still during the daytime
 Usually does not cause circadian rhythm
disruptions -- body cycles remain in phase
 Isolated night shifts (< 1 /week) function as
‘on call’

26
Shift Work
& the
Efficient
Emergency
Department
On Duty
On duty implies time of usual type of work,
not an isolated event
 Often called “Shift Work”
 Several common patterns
 Often a major cause of work dissatisfaction
 Nurses are more likely to have permanently
assigned shifts than physicians (Unionized)

27
Shift Work
& the
Efficient
Emergency
Department
Circadian disruption
Happens when waking / sleeping does not
correspond with innate circadian rhythms
 Desynchronizes physiologic cycles
 Desynchronized systems cause significant
physiologic and psychological malaise
 Sleep at the wrong time IS NOT equivalent
to the same amount of sleep at the right
time.

28
Shift Work
& the
Efficient
Emergency
Department
Chronic circadian disruption
Can cause life-long sleep problems
 Shortens life expectancy
 Worsens psychiatric problems
 Worsens interpersonal skills

29
Shift Work
& the
Efficient
Emergency
Department
Examples of circadian disruption
Jet lag: crossing time zones
 Shift work
 Hospitalization with loss of ‘Zeitgibers”-->
“ICU Psychosis” “Sundowning”
 Even the most rapid physiologic parameters
cannot adjust much faster than one or two
hours per 24

30
Shift Work
& the
Efficient
Emergency
Department
31
Shift Work
& the
Efficient
Emergency
Department
Concept of “Zeitgibers”
Physical and social clues which tell us what
time it is.
 Most powerful is light.
 Others include taste and smell of usual
breakfast food, going to work, sound of
daytime activities, social activities

32
Shift Work
& the
Efficient
Emergency
Department
33
Shift Work
& the
Efficient
Emergency
Department
Shift work
Not a new phenomenon, but now vastly
more frequent.
 25% of American workers are shift workers
at some point in their lives.
 Invention of the light bulb: 1883

34
Shift Work
& the
Efficient
Emergency
Department
Shift work
Work a defined period of time, then off for a
period
 Working time can be at any time of the 24hr day
 Fixed shifts -- working the same time every
day
 Rotating shifts -- working time of day
changes from time to time

35
Shift Work
& the
Efficient
Emergency
Department
36
Shift Work
& the
Efficient
Emergency
Department
Shift work in Industry
Iron foundries and steel mills introduced
shift with with rapid rotation.
 The chrono-stress gave impetus to
unionism.
 Shift work is a major issue in union
negotiations even today

37
Shift Work
& the
Efficient
Emergency
Department
Shift length
Length of shift: most common is 8 hours
 Others are 10, 12 and 6 hours
 More mistakes made in the last 4 hours of a
12 hour shift than in the first 8 hours
 Shift changes become more difficult after
age 40

38
Shift Work
& the
Efficient
Emergency
Department
Do long shifts increase output
per worker?
No.
 Ergonomics, the science of the Industrial
Revolution
 Henry Ford first reduced working shifts
from 12 hours to 8 hour
 Productivity increased
 Length of night shift more crucial than
length of day shift

39
Shift Work
& the
Efficient
Emergency
Department
Serious adverse consequences of
shift work
20% decrease in life span
 62% sleep disturbance
 higher rate of accidents on the job
 high risks of fatal commuting accidents
 800% risk of ulcers
 1500% incidence of depression and mood
swings

40
Shift Work
& the
Efficient
Emergency
Department
41
Shift Work
& the
Efficient
Emergency
Department
Shift work is also linked to:
drug and alcohol abuse
 altered immune response
 infertility in women
 high divorce rate.

42
Shift Work
& the
Efficient
Emergency
Department
43
Drug abuse
Shift Work
& the
Efficient
Emergency
Department
Shift work and the Heart
increased cardiovascular mortality
 (risk worse than smoking a pack of
cigarettes per day)
 risk for dysrhythmias (PVC, MAT, SVT)
 risk of sinus arrest (up to 12 sec in one
study)
 chronic hypertension

44
Shift Work
& the
Efficient
Emergency
Department
Tolerance to shift work
Better in younger persons (under 40, or premenopausal)
 Better in childless persons
 Better in natural owls than natural larks
 20% of people have no trouble changing
shifts,
 60% have moderate hardship, and
 20% have extreme difficulty.

45
Shift Work
& the
Efficient
Emergency
Department
Night People vs. Morning People
Night people = easier adjustment to shift
work
 Tend to be phase delayed
 Day people = harder with shift change;
more stable once adjusted
 Tend to be more synchronized and more
resistant to re-setting
 Residency survey: EP s have more night
types than normal populations

46
Shift Work
& the
Efficient
Emergency
Department
Shift length
Most research has been done on 8 hr shifts
 12 hour shifts no longer permitted in most
industries

47
Shift Work
& the
Efficient
Emergency
Department
Why 8 hour shifts?
Work output per physician (nurse) per hour
is greater with 8 hour shifts.
 Mistakes less per worker with 8 hour shifts
 Patient satisfaction: patients more satisfied
when health care worker is happy
 12 hr shifts appeal most to younger, less
experienced physicians / nurses

48
Shift Work
& the
Efficient
Emergency
Department
Worker wellbeing
Optimum: days only
 Next best: same shift every day, even if not
most suited to your optimal time
 Acceptable: Isolated (night) shifts with core
working time the same each day
 Worst of all: randomly rotating shifts

49
Shift Work
& the
Efficient
Emergency
Department
Shift rotation
patterns
rotating (swing) shifts -- several common
patterns
 “Isolated nights” work one shift regularly,
with “isolated” different shifts no more than
once per week
 randomly rotating shift -- any shift, any day,
no pattern

50
Shift Work
& the
Efficient
Emergency
Department
Swing shifts (rotation patterns)
Phase advance: one week days, one week
evenings, one week nights (can be monthly)
 Phase retreat: (Southern Swing): one week
days, one week nights, one week evenings
 Phase advance is more physiologic and
more easily tolerated
 “Owls” with their innate phase delay,
acclimatize faster and tolerate phase
advance better than “Larks”

51
Shift Work
& the
Efficient
Emergency
Department
Randomly changing shifts
almost universally condemned
 forbidden by most unions
 highest physiologic risk and stress
 practiced mostly by physicians

52
Shift Work
& the
Efficient
Emergency
Department
Isolated nights
defined as less than one night per week
 equivalent to a bad night on call

53
Shift Work
& the
Efficient
Emergency
Department
Adjusting to a new shift
Body can adjust by 1-2 hrs. / 24, or one
week to move forward by one (8 hr) shift.
 Although weekly rotations are most
common, a
 Monthly rotation is better, IF
 Worker will maintain the same sleep/wake
schedule when not working

54
Shift Work
& the
Efficient
Emergency
Department
Downside
Unfortunately, most permanent night
workers switch to day-life when not at work
 Never acclimatize
 Same ill effects as random-shift changers

55
Shift Work
& the
Efficient
Emergency
Department
What about physicians?
MD = Maximum Denial
 Socialized to ignore their own needs
 Trained to be ‘tough’
 poor role models

56
Shift Work
& the
Efficient
Emergency
Department
Performance of physicians

Åkerstedt et al:
documented poor performance with microsleeps (non-restorative) during rote tasks
 documented micro and mini-sleeps during
drive home even in those who did not think
they had slept

57
Shift Work
& the
Efficient
Emergency
Department
58
Physician learning

Asken MJ, Raham DC: Resident Performance and Sleep Deprivation:
A Review. J. Med Educ 1983;58:382-388

Demonstrated decreased performance,
learning of deleterious habits and
physiologic harm.
Shift Work
& the
Efficient
Emergency
Department
59
Overall performance

Tilley et al The sleep and performance of shift workers. Human
Factors, 1982;24:624-41

Found that shift work affected rote tasks and
the highest intellectual tasks equally as
much; moderately challenging but well
known tasks suffered least. Implication for
physicians: we make more mistakes on the
more serious cases
Shift Work
& the
Efficient
Emergency
Department
Implications for the efficient ED
8 hour shifts are optimal
 minimize circadian disruption through
meticulous attention to circadian principles

 Non-sleep-disrupted
physicians and nurses are
more productive and less prone to drug or
alcohol use, and therefore safer for patients and
the employer
60
Shift Work
& the
Efficient
Emergency
Department
Strategies to improve efficiency
of shift workers
Teach and encourage proper sleep hygiene
(literature available upon request)
 Optimize shift rotation patterns
 Provide opportunities for food & exercise
 Encourage social life

61
Shift Work
& the
Efficient
Emergency
Department
62
Shift Work
& the
Efficient
Emergency
Department
Sleep Hygiene
Keep sleep time sacred
 Minimize care-giving responsibilities
during sleep time.
 Optimize sleeping temperature
 Exercise 20 min per day, but at least 1 hr
prior to going to sleep
 “When you feel least like doing it, is when
you need it the most”

63
Shift Work
& the
Efficient
Emergency
Department
Diet
Great care to eat appropriately during the
working / waking time
 Hospitals need to provide access to good,
nutritious food for night workers as well as
day workers
 Eating while socializing is a more powerful
zeitgiber than eating alone.

64
Shift Work
& the
Efficient
Emergency
Department
Light: optimize
single most powerful zeitgiber for
humans
 without adequate light, many
humans never completely adapt to a
new schedule
 intensity is important: 7,000 Lux,
like a heavily overcast day
 most indoor lighting is inadequate

65
Shift Work
& the
Efficient
Emergency
Department
Light: problems
new ‘energy saving’ fixtures are even more
inadequate
 Saving money by putting low output
lighting in the Emergency Department is
false economy.
 implication to hospital administration: high
intensity lights over physicians / nurses
working areas improves productivity and
minimizes mistakes.

66
Shift Work
& the
Efficient
Emergency
Department
Optimize night-shift performance
Light ED at 7000 lux in at least some parts
 Scheduled night hours for the cafeteria -adequate for everyone to get some while
still staffing the ED
 Provide a quiet dark place for worker naps
during breaks
 Exercise facilities on campus improves
worker performance.

67
Shift Work
& the
Efficient
Emergency
Department
Scheduling to optimize worker
performance
8 hour shifts
 Permanent night shift workers (days,
evenings, nights)
 Night differential is helpful in recruiting
permanent night workers
 Rotations: equal distribution of undesirable
shifts

68
Shift Work
& the
Efficient
Emergency
Department
Creative scheduling: ultra short
Ultra-short night shift: night shift is only 6
hours long; it provides time for the worker
to sleep before and after the shift.
 Minimizes circadian disruption. Works best
with Isolated Night pattern and next best
with Random Rotation

69
Shift Work
& the
Efficient
Emergency
Department
Creative Scheduling: split night
Split night: One shift ends very, very late
(say 3 am) and the next starts very, very
early (3 am)
 Each person gets to sleep part of the normal
night time, and be up during most of the
normal day. Excellent commuting
conditions, too.

70
Shift Work
& the
Efficient
Emergency
Department
Exercise
Athletes: get more delta
(SWS, restorative) sleep.
 Time of day important: pm
exercise has more effect.
 Exercise should be over
more than one hour before
sleep time

71
Shift Work
& the
Efficient
Emergency
Department
Exercise implications for the
workplace
Exercise at the workplace enhances
alertness and worker wellbeing
 Brief episodes of vigorous exercise
enhances alertness -- 10 min in middle of
the night
 Exercise improves sleep quality -- if
completed at least 1 hour before sleep time
 Exercise before driving home -- fewer
accidents during commute

72
Shift Work
& the
Efficient
Emergency
Department
Socialization
An important zeitgiber for humans
 Improves workforce wellbeing
 Social Life is main cause of night-workers
NOT maintaining same schedule on daysoff. Night workers need a social life, too
 Spouses must be supportive

73
Shift Work
& the
Efficient
Emergency
Department
74
Shift Work
& the
Efficient
Emergency
Department
The employer can:
Encourage off-duty night workers to
socialize during their normal waking hours
 Notify night workers of other night-time
opportunities.
 Involve spouses in learning about shift work
and sleep hygiene

75
Shift Work
& the
Efficient
Emergency
Department
Summary

Emergency Medicine is of necessity 24 / 7
 physicians,
nurses, clerks, aides,
housekeeping...

76
Careful attention to circadian issues and
shift scheduling can improve worker
efficiency, improve retention, improve
community relations, reduce medical
mistakes...
Shift Work
& the
Efficient
Emergency
Department
Best single reference
"Why we Sleep" by James Horne. Published
by Oxford University Press Walton St
Oxford OX2 6DP 1988
 a classic overall reference

77
Shift Work
& the
Efficient
Emergency
Department
78