Topic 4: Ergonomics - Human Factors: Drews & Doig (2014) Flashcards
(Topic 4: Drews & Doig) What did this study investigate.
Investigated the benefits that might be gained by presenting nurses in ICU with information about patients in a graphical form rather than numerical.
(Topic 4: Drews & Doig) Describe the purpose of ICU machines. (4)
1) In ICU patients receive continuous monitoring as they are critically ill.
2) Generally monitored includes BP, oxygen saturation, heart & respiratory rates.
3) Monitoring displays tend to show data on vital signs in numerical form.
4) There is usually a sub-menu to access trends in data (slowing down/speeding up) but this is not on the main screen.
(Topic 4: Drews & Doig) What was the aim of this study?
The aim was to develop and evaluate a configural vital signs display that would help nurses in the rapid detection and identification of physiological deterioration in a patient by presenting data graphically instead of just in numerical form.
(Topic 4: Drews & Doig) What would the nurses receive? (3)
1) Numerical data on heart rate, BP, oxygen saturation.
2) Graphically presented trend data for the above measures to the left of each numerical display.
3) Graphically presented data indicating degree of variability in the patients physiology over time and their current state. A thin grey rectangle indicated normal thresholds. A solid white rectangle indicated the extent of variation over the previous hour.
(Topic 4: Drews & Doig) What were the shapes and colours used for?
To increase the speed at which information could be processed.
(Topic 4: Drews & Doig) What did the boundaries of the white rectangle represent?
The left boundary represented the patients lowest heart rate value, and the right boundary the highest heart rate value.
(Topic 4: Drews & Doig) What was the patient’s current state represented by?
A current state object (CSO), if it was close to the edge of the white rectangle this would indicate ongoing vital sign changes but if it was central then this indicated stability.
(Topic 4: Drews & Doig) What did the colour of the CSO reflect?
Blood oxygen saturation %’s with red being high and blue being the lowest.
(Topic 4: Drews & Doig) What type of experiment was it?
Laboratory
(Topic 4: Drews & Doig) What was the independent variable?
Whether the nurse was asked to interpret data presented in a traditional numerical format or whether the nurse was asked to interpret data using the CVS display.
(Topic 4: Drews & Doig) What was the dependent variable?
The response time and accuracy in clinical data interpretation (assessed across four scenarios).
(Topic 4: Drews & Doig) Where did this experiment take place?
The simulation took place in the Applied and Basic Cognition Laboratory of the Department of Psychology at the University of Utah. Therefore, the environment was artificial and did not take place in the workplace.
(Topic 4: Drews & Doig) Describe the sample for this study.
42 registered nurses with a minimum of 1 year of ICU experience.
21 in each condition CVS display or control group
Age range 25-64, 69% female
(Topic 4: Drews & Doig) Method: What was each nurse presented with?
4 different patient scenarios (designed by ICU Dr and nurse).
(Topic 4: Drews & Doig) Method: What was each nursed instructed to do?
To verbally evaluate each patient’s physiological status, interpret the data & recommend interventions as quickly & accurately as possible.
(Topic 4: Drews & Doig) Method: What information was each nurse given.
Patient medical history, previous & current medications.
(Topic 4: Drews & Doig) Method: How long did each nurse have to complete each scenario.
5 minutes
(Topic 4: Drews & Doig) Method: How did each nurse receive information.
On a 15 inch desktop but half of them received info via a configural vital signs display (CVS) and the other half via a traditional ICU numerical data display (trend data was accessible through a single key press).
(Topic 4: Drews & Doig) Method: Was the scenario presentation order planned or randomised.
Randomised
(Topic 4: Drews & Doig) Method: What did each nurse do after they completed all 4 scenarios?
All nurses completed a questionnaire on the tasks, including the level of mental demand associated with the task.
(Topic 4: Drews & Doig) Results: Describe the results regarding response time.
Nurses in CVS display condition identified the patient’s state 48% quicker than those in the control display condition in the septic shock scenario & 38% quicker in the pulmonary embolism scenario.
They were also significantly quicker to identify the condition of the patient in the stable scenario.
(Topic 4: Drews & Doig) Results: Describe the results regarding accuracy of the nurses assessments.
Accuracy of nurses assessments improved by 1/3 or more when using CVS display vs control display in septic shock & pulmonary embolism scenarios.
(Topic 4: Drews & Doig) Results: Describe results regarding mental demand.
Nurses reported significantly lower mental demand in the CVS display condition than control condition.
(Topic 4: Drews & Doig) Conclusions: Describe conclusions regarding speed and accuracy.
Providing patient information in a configural display with readily visible trends and data variability can improve the speed and accuracy of data interpretation by ICU nurses.
