1. Human Factors Assessment of the Emergency Department
Zheng Yan
Advised by:
Dr. Dan France

2. Overall Objective
To determine what human and system factors effect perceived workload in ED physicians
Hypothesis: The higher the perceived workload, the higher the stress and the higher the probability of committing medical errors.
Objective: To create changes in ED work environment and work processes that will reduce high workload, stress, and risk of committing medical errors.

3. BME 273 Objectives
Time-motion, primary task analysis on 5 ED physicians
3 attending
2 residents
Create workload signals for individual physicians based on task analysis
Identify sources of increased workload and show their impact on workload curves
Provide input to improve future study in pediatric ED

4. Background (Studies)
Two large studies conducted by the Institute of Medicine (IOM) found that adverse events occurred in 2.9 to 3.7% of hospitalizations.
“An adverse event is an injury caused by medical management rather than the underlying condition of the patient.”
— Institute of Medicine

5. Background (Studies)
In Colorado and Utah hospitals, 8.8% of the adverse events lead to death.
The data from the studies suggest that 44, , 000 Americans die each year as a result of medical errors.
National problem: ED are overcrowded
ED physicians experience high levels of stress and burn-out

6. Background (ED Cases)
27 year-old patient with leukemia died after erroneous intrathecal administration of vincristine
Drug should have been given intravenously
2 year old baby died from a lethal dose of sedative promethazine, instead of anti-convulsant phenobarbital
Mix of medications in zipper bag where drugs were kept, because drugs had similar names, and ampoules looked alike

7. ED Research Similar research
Hollingsworth JC study – studies how doctors and nurses spend their time in the ER
Hymel G. study – looks at shiftwork interruption in ER
Louis Graff study – looks at ER staff workload
Coiera E., and Chisholm studied interruptions and communication patterns in the ED

8. Student Research Last year BME project
focused on physician interruptions
30 % (average) of physician’s time was spent on interruptions (ie. conversing with other physicians)
helped set up the list of tasks used to record the physician task load on the palm pilot

9. Problem Vanderbilt ER has 6 residents and 2 attendings for each shift.
ER sees about patients a year
The ER built in 1970’s was designed for only patients a year.
Number of potential errors unknown, due to lack reporting by doctors and nurses
New on-line reporting system just implemented throughout all of VUMC

10. Study Design Time-motion, primary task analysis
180-minute periods of direct observation
Observe/shadow one attending or resident at a time
Duration and task type are recorded continuously
Physiological/physical activity data and whiteboard data is collected simultaneously
Subjective workload scores are collected at end of observational period

11. Primary Task Analysis
180-minute observation periods (Real-time data collection using Palm Pilots)
Example of of an observation period.
ObservationDate CurrentTask TaskStart TaskStop
9/18/2003 Direct Patient Care 9/18/2000 3:04:09 PM 9/18/2000 3:09:00 PM
9/18/2003 Charting /18/2000 3:09:34 PM 9/18/2000 3:10:11 PM
9/18/2003 Getting Old Records 9/18/2000 3:10:16 PM 9/18/2000 3:10:23 PM
9/18/2003 Direct Patient Care 9/18/2000 3:11:03 PM 9/18/2000 3:11:29 PM

12. Measurements Categories Number and type of tasks completed
Average time to complete tasks (continuous – minutes)
Without interruptions
With interruptions
· Steps traveled (walked) (pedometer reading - continuous)
· Time in motion (minutes - continuous)

13. Measures (Cont.)
· Number of patients managed simultaneously (continuous)
· Total number of unique patients managed (continuous)
Patient acuity
· Number of tasks performed (continuous)
· Average direct patient care time (minutes – continuous)

14. Measures (cont.) Pedometer – rough estimate of distance doctors travel
SenseWear Arm band – measures galvanic skin response to record stress
RT3 Acceleromter – measure motion in the 3 dimensions
NASA TLX – multidimensional measures of perceived workload;
Provides overall workload and sources of workload: frustration, mental demands, temporal demands, physical demands, performance

15. Results Subjects observed: 1 attending; 2 residents
Task counts (average)
Attending: 107 (1 min, 11 sec); Exchanging pt info
Residents: 94 (1 min, 20 sec); exchanging pt info/charting
Interruptions:
Attending: 15 (every 8.5 min)
Residents: 11 (every 12.3 min)
Physiological/physical activity data has not downloaded or analyzed yet.

16. Workload and Whiteboard Data

17. Workload Signal for Attending #1
Time (min)

18. Future Work Complete physician observations in ED (N=5)
Analyze physiological/physical activity data
Analyze and compare data across physician training levels (with Dr France, Scott Levin)
Study/interpret trends in workload and factors that influence workload.