There is interest in how clinicians can achieve good awareness of their patients’ wellbeing in a way that is not provided by conventional alarms. Earcons (short abstract sound motifs) provide an alternative. In three experiments we explored how effectively normal and abnormal levels of a patient's heart rate (HR), arterial oxygen saturation (SpO2) and blood pressure (BP) could be conveyed using two different earcon designs: overlapping (individual earcons for each vital sign played at the same time) or serial (individual earcons played one after the other). HR was mapped to the tremolo (sound vibration) rate in short bursts of white noise, SpO2 was mapped to the relative pitch of a tone, and BP was mapped to the range of an upward or downward sweep of pitch (chirp) of a tone. Experiment 1 compared how well non-clinician participants could identify HR and SpO2 using overlapping and serial mappings and found no difference in accuracy either for mapping or across vital signs. Experiment 2 added the BP vital sign, and compared overlapping and serial mappings. Identification accuracy was better with the serial mapping than with the overlapping mapping, and better for HR than for either SpO2 or BP. Experiment 3 replicated Experiment 2 but added conditions in which participants were cued to report a single vital sign in order to check whether memory limits or output interference were constraining the ability to report vital signs. When the cue appeared after the earcons were played, approximating a classic partial report paradigm, there was no improvement in identification accuracy, suggesting that earcon interpretability rather than memory load or output interference was constraining responses. However, when the cue appeared before the earcons were played, identification improved, suggesting that focused attention aided interpretation of the earcons. Although design modifications are needed, the results suggest that three vital signs may best be displayed in serial presentation for clinicians to maintain awareness of a patient's wellbeing in a convenient eyes-free manner.

OBJECTIVE: To understand the complex effects of interruption in healthcare. MATERIALS AND METHODS: As interruptions have been well studied in other domains, the authors undertook a systematic review of experimental studies in psychology and human-computer interaction to identify the task types and variables influencing interruption effects. RESULTS: 63 studies were identified from 812 articles retrieved by systematic searches. On the basis of interruption profiles for generic tasks, it was found that clinical tasks can be distinguished into three broad types: procedural, problem-solving, and decision-making. Twelve experimental variables that influence interruption effects were identified. Of these, six are the most important, based on the number of studies and because of their centrality to interruption effects, including working memory load, interruption position, similarity, modality, handling strategies, and practice effect. The variables are explained by three main theoretical frameworks: the activation-based goal memory model, prospective memory, and multiple resource theory. DISCUSSION: This review provides a useful starting point for a more comprehensive examination of interruptions potentially leading to an improved understanding about the impact of this phenomenon on patient safety and task efficiency. The authors provide some recommendations to counter interruption effects. CONCLUSION: The effects of interruption are the outcome of a complex set of variables and should not be considered as uniformly predictable or bad. The task types, variables, and theories should help us better to identify which clinical tasks and contexts are most susceptible and assist in the design of information systems and processes that are resilient to interruption.

OBJECTIVE: To examine the effect of interruptions and task complexity on error rates when prescribing with computerized provider order entry (CPOE) systems, and to categorize the types of prescribing errors. DESIGN: Two within-subject factors: task complexity (complex vs simple) and interruption (interruption vs no interruption). Thirty-two hospital doctors used a CPOE system in a computer laboratory to complete four prescribing tasks, half of which were interrupted using a counterbalanced design. MEASUREMENTS: Types of prescribing errors, error rate, resumption lag, and task completion time. RESULTS: Errors in creating and updating electronic medication charts that were measured included failure to enter allergy information; selection of incorrect medication, dose, route, formulation, or frequency of administration from lists and drop-down menus presented by the CPOE system; incorrect entry or omission in entering administration times, start date, and free-text qualifiers; and omissions in prescribing and ceasing medications. When errors occurred, the error rates across the four prescribing tasks ranged from 0.5% (1 incorrect medication selected out of 192 chances for selecting a medication or error opportunities) to 16% (5 failures to enter allergy information out of 32 error opportunities). Any impact of interruptions on prescribing error rates and task completion times was not detected in our experiment. However, complex tasks took significantly longer to complete (F(1, 27)=137.9; p<0.001) and when execution was interrupted they required almost three times longer to resume compared to simple tasks (resumption lag complex=9.6 seconds, SD=5.6; resumption lag simple=3.4 seconds, SD=1.7; t(28)=6.186; p<0.001). CONCLUSION: Most electronic prescribing errors found in this study could be described as slips in using the CPOE system to create and update electronic medication charts. Cues available within the user interface may have aided resumption of interrupted tasks making CPOE systems robust to some interruption effects. Further experiments are required to rule out any effect interruption might have on CPOE error rates.