Human Factors Engineering and Patient Safety

1
Human Factors Engineering and Patient Safety

• John Gosbee, MD, MS
• VA National Center for Patient Safety
• John.Gosbee_at_med.va.gov www.patientsafety.gov

2
Overview

• Basics of HFE
• HFE and patient safety demonstrations
• HFE and patient safety exercise

3
What is Human Factors Engineering?

• Designing systems devices, software, and tools to
  fit human capabilities and limitations
• Using methods to gather unique information on
• Hidden needs of the end-user
• Unexpected interactions between the system and
  the end-user
• Taking advantage of knowledge bases about
  human-system interaction

4
Human Factors Model

• Psychomotor
• Hand
• - Feet

• Input Devices
• Buttons
• - Foot pedal

INTERFACE
Senses - Vision - Hearing
Output - CRT - Sound
5
Broad Impact of Human Factors Engineering

• Aviation (since 1940s)
• Nuclear Power
• Space flight
• Computer software and hardware (Xerox PARC 1970s)
• Consumer products (Palm Pilot, Snakelight)
• Railroad, motor vehicle, farm machinery, etc.

6
Radar Scope to Detect enemy ships
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Performance Graph (curve)
100
90
80
70
Performance
1
2
3
4
Time (hours)
8
Performance Graph (curve)
100
90
80
70
Performance
1
2
3
4
Time (hours)
9
How can we move the curve upwards?
100
90
80
70
Performance
1
2
3
4
Time (hours)
10
Demonstration with a Patient Safety Twist

• Look at the next slide
• Count the number of words in the paragraph that
  are repeated

11
Exercise

• The last time we got together to camp in Nova
  Nova Scotia we we decided that it would be too
  cold to sleep in a tent. So, I called the motel
  motel that was located near Peggys Cove on on
  top of the hill. We should call each other and
  talk about these plans once and for all. If you
  cannot call me, the the best way to get in touch
  is by fax fax machine.

12
Exercise

• The last time we got together to camp in Nova
  Nova Scotia we we decided that it would be too
  cold to sleep in a tent. So, I called the motel
  motel that was located near Peggys Cove on on
  top of the hill. We should call each other and
  talk about these plans once and for all. If you
  cannot call me, the the best way to get
  in touch is by fax fax machine.
• Answer is 3?

13
Exercise

• The last time we got together to camp in Nova
  Nova Scotia we we decided that it would be too
  cold to sleep in a tent. So, I called the motel
  motel that was located near Peggys Cove on on
  top of the hill. We should call each other and
  talk about these plans once and for all. If you
  cannot call me, the the best way to
  get in touch is by fax fax machine.
• Or is the answer 6?or is it 14?

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Medical Device Correlation

• What does this phrase mean ? Telemetry Off
• To a novice? To an expert?

15
Demonstration Stroop Effect
Row 1
Row 2
Row 3
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Now, State the Color of the Text as Fast as You
Can
Yellow
Green
Red
Blue
Row 1
Green
Red
Blue
Yellow
Row 2
Red
Blue
Yellow
Green
Row 3
17
Again, State the Color of the Text as Fast as
You Can
Red
Blue
Green
Yellow
Row 1
Yellow
Green
Red
Blue
Row 2
Blue
Yellow
Green
Red
Row 3
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Tell the nursing student to attach the oxygen
mask and tubing to the green spigot
Patient Safety Correlation
For further info, see http//faculty.washington.ed
u/chudler/words.htmlseffect
J. Ridley Stroop (1935) Studies of
Interference in Serial Verbal Reactions. Journal
of Experimental Psychology, vol 18, 643-662
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Weaker vs. Stronger Remedy
Better
Make sure to use the correct color Adaptor!?
20
(No Transcript)
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(No Transcript)
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Sources Medical Mistake Left Newborn In
Coma KITV-TV HONOLULU - A medical mistake at
Tripler Army Medical Center has left a newborn
baby in a coma with severe brain damage. Sources
familiar with this case tell KITV 4 News that
Tripler officials apologized to the family of a
baby boy born there in January after he was
mistakenly given carbon dioxide right after
birth, instead of oxygen. The baby boy was born
Jan. 14 at Tripler Army Medical Center during a
scheduled cesarean section delivery, sources told
KITV 4 News. They said medical personnel
mistakenly gave him carbon dioxide immediately
after birth instead of oxygen. Sources said the
operating room may have been set up incorrectly.
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Another Illusion

• When I say up, everyone raise your hand as
  quickly as you can

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Medical Software Correlation
- Pharmacist uses 95 of time - Enter button to
enter data
- Pharmacist uses 5 of time - Spacebar to
enter data
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Video Demo

• Count the number of passes made between
  basketball players wearing white
• Write down your answer (quietly not a group
  effort)
• At the end, I will ask for answers

26
HFE and Patient Safety Lesson

• We often have a pre-set focus during
  interpretation
• How much can a clinician attend to in an ICU
  room?
• Patient
• Monitor
• IV Pump

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How Big a Role is HFE?

• 99 of all adverse events?
• See recent analysis of 252 laparoscopic bile duct
  injury cases (Way LW, et al. Ann Surg.
  2003237(4) 460-9)
• One in a Thousand or One in Five?
• Recent JAMA article (Samore)
• From 0.1 to 17 of all admissions to 3 different
  hospitals in Utah
• From self report (technique) to observation to
  trigger tools

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Broad Impact of Human Factors Engineering

• Aviation (since 1940s)
• Nuclear Power
• Space flight
• Computer software and hardware (Xerox PARC 1970s)
• Consumer products (Palm Pilot, Snakelight)
• Railroad, motor vehicle, farm machinery, etc.

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Human Factors Engineering and Your World

• Anesthesiology
• Design of alarms, monitors, and safety systems
• Emergency Medicine
• Design of decision-making tools and monitoring
• Surgery
• Design of hand tools and visualization devices
  (laparoscopy)

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Healthcare SystemsRange from the Simple to
Complex

• Syringe, catheter bag and its tubing
• O2 cylinder, ECG machine, IV pump
• Code cart, anesthesia work station
• Hospital computer system
• MRI control room and suite
• ICU, ED, OR

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Human Factors Engineering is about the whole
system

• Whats the design of the training and education
• Labeling and instructions attached to device
• Policy and procedures?
• Information displays
• Pieces of paper
• Layout and structure of the room, layout of the
  floor, layout of the facility, overall environment

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Design and Test of Written Documents

• Policies and procedures
• Steps to use a device
• Instructions or help screen for software
• Double Checks for PCA programming
• Results from usability testing at University
  Health Network

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Core Concepts of HFE

• Learned intuition
• Assumptions Metaphors
• We can never recall not having known itand, we
  cannot imagine someone else does not know it
• Normalization of Complexity
• Encouraged, if not rewarded

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Learned intuition examples

• Secretaries learning computers in early 1980s
• Floppy Disk
• Mouse
• Other examples?

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The Normalization of Complexity

• Healthcare workers compensate for complex,
  unclear workplaces and devices
• IV Pumps, for example
• Unclear or absent information or cues to
  understand how to accomplish desired goal
• Mastery of the complex becomes a normal strategy,
  without regard to reasonableness or necessity of
  complexity

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Human factors engineering and patient safety case
studies

• Code Cart drawer
• PCA pump

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Baseline Drawer (Laundry hamper)Range
243-358 min, Avg307 min
Note the multiple orientations
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Code Cart Drawer Fifth Version Range 55-125
min, Avg108
Note the lack of labels for each spot
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PCA Interface Redesign Univ. Toronto
Existing Design
New Design
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PCA Programming Sequence Redesign
Existing Design
New Design
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Usability Evaluation of a PCA Pump Measurements

• Programming Errors Measured
• Quantity
• Severity
• Performance Measured
• Programming Time
• Task completion time
• Mental Workload Ratings ? NASA-TLX

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PCA Pump Errors - Results

• New Interface
• 55 reduction in number of errors
• Zero errors in entering drug concentration
• Old interface
• 8 drug concentration errors were made
• 3 of these were not detected and were left
  uncorrected
• Mode Errors
• Old interface errors involved selecting the wrong
  mode (11 errors, 9 of which were eventually
  corrected
• With the new interface, only 3 such mode
  selection errors occurred, all of which were
  eventually corrected

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Other Results

• Task Completion Time
• 11/12 end-users faster with new interface
• Average 18 faster
• No difference in Subjective Workload
• Over 90 preference for new interface

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Who else includes HFE?

• Nursing Schools (as part of survey or informatics
  courses)
• Western Michigan University (since 1995)
• University of Missouri (2003)
• Nursing board for healthcare informatics
  certification
• Pharmacy Schools (as part of medication safety
  courses)
• University of Wisconsin (since 2002)
• Ohio State (2000?, contact is Phil Schneider)
• Medical Schools (as part of patient safety)
• UC-San Diego
• University of Miami

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Academia

• University of Wisconsin
• Series of courses for masters in HFE and patient
  safety
• Students from nursing, medicine, engineering
• HFE and BME key to research agenda
• http//www.engr.wisc.edu/ie/
• University of Maryland
• Video analysis in OR and ED
• Alarms redesign
• HFE and BME key to DCERPS
• http//www.safetycenter.umm.edu/

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Conclusions

• Human factors engineering is to patient safety as
  microbiology is to infection control
• HFE concepts physiology and anatomy
• HFE tools diagnostic testing

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HFE Web Resources

• VA Web Site http//www.patientsafety.gov/hf.html
  
• Wiklund M. Eleven Keys to Designing
  Error-Resistant Medical Devices. MDDI. May
  2002 pp. 86-90. http//www.devicelink.com/mddi/ar
  chive/02/05/004.html
• FDA Web Site and Publications (free and good!)
• http//www.fda.gov/cdrh/humanfactors/
• Human Factors Engineering and Medical Devices
  (Do It By Design Device Use Safety)

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Bibliography

• Gosbee JW. Introduction to the human factors
  engineering series. Joint Commission Journal on
  Quality and Safety. 2004 30(4) 215-219.
• Gosbee JW, Anderson T. Human factors engineering
  design demonstrations can enlighten your RCA
  team. Quality Safety in Health Care. 2003
  12 119-121. http//qhc.bmjjournals.com/cgi/conten
  t/abstract/12/2/119?etoc