Organizing Audible Alarm Sounds in the Hospital: A Card-Sorting Study

Auditory Sequences Presented With Spearcons Support Better Multiple Patient Monitoring Than Single-Patient Alarms: A Preclinical Simulation

OBJECTIVE

A study of auditory displays for simulated patient monitoring compared the effectiveness of two sound categories (alarm sounds indicating general risk categories from international alarm standard IEC 60601-1-8 versus event-specific sounds according to the type of nursing unit) and two configurations (single-patient alarms versus multi-patient sequences).

BACKGROUND

Fieldwork in speciality-focused high dependency units (HDU) indicated that auditory alarms are ambiguous and do not identify which patient has a problem. We tested whether participants perform better using auditory displays that identify the relevant patient and problem.

METHOD

During simulated patient monitoring of four patients in a respiratory HDU, 60 non-clinicians heard either (a) IEC risk categories as single-patient alarm sounds, (b) event-specific categories as single-patient alarm sounds, (c) IEC risk categories in multi-patient sequences or (d) event-specific categories in multi-patient sequences. Participants performed a perceptual-motor task while monitoring patients; after detecting abnormal events, they identified the patient and the event.

RESULTS

Participants hearing multi-patient sequences made fewer wrong patient identifications than participants hearing single-patient alarms. Advantages of event-specific categories emerged when IEC risk category sounds indicated more than one potential event. Even when IEC and event-specific sounds indicated the same unique event, spearcons supported better event identification than did auditory icon sounds.

CONCLUSION

Auditory displays that unambiguously convey which patient is having what problem dramatically improve monitoring performance in a preclinical HDU simulation.

APPLICATION

Time-compressed speech assists development of detailed risk categories needed in specific HDU contexts, and multi-patient sound sequences allow multiple patient wellbeing to be monitored.

Applying Human Factors Engineering to Address the Telemetry Alarm Problem in a Large Medical Center

OBJECTIVE

Address the alarm problem by redesigning, reorganizing, and reprioritizing to better discriminate alarm sounds and displays in a hospital.

BACKGROUND

Alarms in hospitals are frequently misunderstood, disregarded, and overridden.

METHOD

Discovery-oriented, intervention, and translational studies were conducted. Study objectives and measures varied, but had the shared goals of increasing positive predictive value (PPV) of critical alarms by reducing low-PPV alarms in the background, prioritizing alarms, redesigning alarm sounds to increase information content, and transparently conveying who initiated alarms. An alarm ontology was iteratively generated and refined until consensus was achieved.

RESULTS

The ontology distinguishes five levels of urgency that incorporate likely PPV, three categories for who initiates the alarm (hospital staff, patient, or machine), whether it is clinical or technical, and clinical functions.

CONCLUSION

This unique collaboration allowed us to make progress on the alarm problem by making unintuitive leaps, avoiding common missteps, and refuting conventional healthcare approaches.

APPLICATION

Hospitals can consistently redesign, reorganize, reprioritize, and better discriminate alarms by priority, PPV, and content to reduce nurse response times.

Nurses' use of auditory alarms and alerts in high dependency units: A field study

A fieldwork study conducted in six units of a major metropolitan Australian hospital revealed that nurses' attitudes towards alarms are influenced by each unit's physical layout and caseload. Additionally, nurses relied heavily on both non-actionable and actionable alarms to maintain their awareness of the status of their patients' wellbeing, and used auditory alarms beyond the scope of their intended design. Results suggest that before reducing or removing auditory alarms from the clinical environment to improve patient safety, it is important to understand how nurses in different clinical contexts use current alarm systems to extract meaningful information. Such an understanding could guide appropriate alarm reduction strategies and guide alternative design solutions to support nurses' situation awareness during monitoring.

Need for a new paradigm in the design of alarms for patient monitors and medical devices

Modern computerised medical devices emit large numbers of tone-based alerts and alarms. Notifications that comprise auditory icons or natural human speech substantially increase the psychological salience of alerts and alarms and may allow a larger set of notifications to be used, as they do not require memorisation of arbitrary sounds.