Interruptions in the emergency department can lead to errors


by Nancy Walsh

Busy clinicians in the emergency department reduce the time they spend on clinical tasks when interrupted, working faster and possibly cutting corners, a prospective observational study found.

Overall, clinicians were interrupted 6.6 times per hour, and 11% of all tasks were interrupted, according to Johanna I. Westbrook, PhD, of the University of Sydney, in Australia, and colleagues.

The mean “time on task” for uninterrupted tasks was 1 minute and 26 seconds (95% CI 1:23 to 1:29), which doubled with one interruption to 3 minutes (95% CI 2:45 to 3:17).

However, when the effect of interruptions was adjusted for length-biased sampling (the longer it takes to complete a task, the greater the chance of that task being interrupted), the time on task was consistently shorter, regardless of the hourly interruption rate, the researchers reported online in Quality and Safety in Health Care.

Experimental work has shown that interruptions can result in lapses in memory, attention, and perception. They also contribute to cognitive load, increase stress, and can interfere with decision-making performance.

Hospitals have been described as high interruption environments, which are a potential source of clinical errors such as failing to complete or initiate tasks.

“Our own research has demonstrated that interruptions to hospital nurses significantly increase the rate and severity of medication administration errors,” the researchers said (See Interruptions Risk Medication Errors by Nurses).

Emergency physicians in particular work in high pressure environments, with high rates of interruption and multitasking.

“Their environment is dynamic, characterized by resource and time constraints, and has been identified to be at greater risk of errors than many other settings,” the researchers explained.

To explore the association between rates of interruption and task completion times and rates in this setting, Westbrook and colleagues conducted a time and motion study in the emergency department of a 400-bed metropolitan teaching hospital.

During 210.45 hours of observation, there were 9,588 individual task actions, for a total time on task of 237.9 hours.

Without adjustment for length-biased sampling, time on task was significantly associated with the number of interruptions: With three or more interruptions, time on task increased by 493% from 1 minute 26 seconds to 7 minutes 4 seconds (95% CI 6:05 to 8:02), the researchers said.

But after adjusting for length-biased sampling, the average time on task was lower than expected.

For instance, in observation periods when there were low numbers of interruptions (3.3 per hour), average time on task predicted by length-biased sampling was longer than the observed average time.

With one interruption, the predicted time was 5.88 minutes and the observed time was 3.28 minutes. With three or more interruptions, the predicted time was 23.07 minutes and the observed time was 6.27 minutes.

In observation periods with the highest numbers of interruptions (15.4 per hour), with one interruption the predicted time was 4.50 minutes while the observed time was 2.02 minutes. With three or more interruptions, the predicted time was 18.63 minutes and the observed time was 4.98 minutes.

Their study was unable to provide an explanation for these apparently contradictory results, though several explanations are possible, they said.

The most likely explanation was that once clinicians were interrupted they compensated for lost time by working faster, reducing effort spent on individual task elements, or eliminating some task elements.

“As individuals are interrupted, they compensate by working faster and cutting corners,” Westbrook and colleagues wrote.

Other experimental studies have shown similar results, with interrupted tasks being completed quickly but with lower accuracy and less frequent completion rates.

Clearly, interruptions and multitasking are unavoidable in a busy environment such as an emergency department.

However, having uncontrolled interruptions in clinical practice “is an expensive and dangerous strategy, and the need to develop clinical processes that minimize unnecessary interruptions and multitasking is strong,” they stated.

The use of a controlled laboratory design as was done in this study is both a strength and a weakness, the authors noted. Its strength lies in the ability to control the types and frequency of tasks and interruptions, while a weakness is its simplification compared to real-world environments.

Additional limitations of the study were its focus on a single department, and the fact that only weekday work was examined.

The results of their study support the hypothesis that the highly interruptive nature of busy clinical environments may have a negative impact on patient safety, the researchers said.

If the results can be confirmed in further studies, “attention should be devoted to substantial redesign of clinical work processes to minimize these expensive task-management behaviors.”

Nancy Walsh is a MedPage Today contributing writer.

Originally published in MedPage Today. Visit for more hospital news.