Effects of multitasking on interpreting a spearcon sequence display for monitoring multiple patients.

Spearcons are time-compressed speech phrases. When arranged in a sequence representing vital signs of multiple patients, spearcons may be more informative than conventional auditory alarms. However, multiple resource theory suggests that certain timeshared tasks might interfere with listeners' ability to understand spearcons. We tested the relative interference with spearcon identification from the following ongoing tasks: (1) manual tracking, (2) linguistic detection of spoken target words, (3) arithmetic true-false judgments, or (4) an ignored background speech control. Participants were 80 non-clinicians. The linguistic task worsened spearcon identification more than the tracking task, p < .001, and more than ignored background speech, p = .012. The arithmetic task worsened spearcon identification more than the tracking task, p < .001. The linguistic task and arithmetic task both worsened performance, p = .674. However, no ongoing task affected participants' ability to detect which patient(s) in a sequence had abnormal vital signs. Future research could investigate whether timeshared tasks affect non-speech auditory alerts.

Enhanced Neonatal Pulse Oximetry Sounds for the First Minutes of Life: A Laboratory Trial.

OBJECTIVE: Auditory enhancements to the pulse oximetry tone may help clinicians detect deviations from target ranges for oxygen saturation (SpO2) and heart rate (HR). BACKGROUND: Clinical guidelines recommend target ranges for SpO2 and HR during neonatal resuscitation in the first 10 minutes after birth. The pulse oximeter currently maps HR to tone rate, and SpO2 to tone pitch. However, deviations from target ranges for SpO2 and HR are not easy to detect. METHOD: Forty-one participants were presented with 30-second simulated scenarios of an infant's SpO2 and HR levels in the first minutes after birth. Tremolo marked distinct HR ranges and formants marked distinct SpO2 ranges. Participants were randomly allocated to conditions: (a) No Enhancement control, (b) Enhanced HR Only, (c) Enhanced SpO2 Only, and (d) Enhanced Both. RESULTS: Participants in the Enhanced HR Only and Enhanced SpO2 Only conditions identified HR and SpO2 ranges, respectively, more accurately than participants in the No Enhancement condition, ps < 0.001. In the Enhanced Both condition, the tremolo enhancement of HR did not affect participants' ability to identify SpO2 range, but the formants enhancement of SpO2 may have attenuated participants' ability to identify tremolo-enhanced HR range. CONCLUSION: Tremolo and formant enhancements improve range identification for HR and SpO2, respectively, and could improve clinicians' ability to identify SpO2 and HR ranges in the first minutes after birth. APPLICATION: Enhancements to the pulse oximeter tone to indicate clinically important ranges could improve the management of oxygen delivery to the neonate during resuscitation in the first 10 minutes after birth.

Attention to Changes on a Head-Worn Display: Two Preclinical Studies with Healthcare Scenarios.

OBJECTIVE: In two experiments, we examined how quickly different visual alerts on a head-worn display (HWD) would capture participants' attention to a matrix of patient vital sign values, while multitasking. BACKGROUND: An HWD could help clinicians monitor multiple patients, regardless of where the clinician is located. We sought effective ways for HWDs to alert multitasking wearers to important events. METHODS: In two preclinical experiments, university student participants performed a visuomotor tracking task while simultaneously monitoring simulated patient vital signs on an HWD to detect abnormal values. Methods to attract attention to abnormal values included highlighting abnormal vital signs and imposing a white flash over the entire display. RESULTS: Experiment 1 found that participants detected abnormal values faster with high contrast than low contrast greyscale highlights, even while performing difficult tracking. In Experiment 2, a white flash of the entire screen quickly and reliably captured attention to vital signs, but less so on an HWD than on a conventional screen. CONCLUSION: Visual alerts on HWDs can direct users' attention to patient transition events (PTEs) even under high visual-perceptual load, but not as quickly as visual alerts on fixed displays. Aspects of the results have since been tested in a healthcare context. APPLICATION: Potential applications include informing the design of HWD interfaces for monitoring multiple processes and informing future research on capturing attention to HWDs.

The Use of Head-Worn Displays for Vital Sign Monitoring in Critical and Acute Care: Systematic Review.

BACKGROUND: Continuous monitoring of patient vital signs may improve patient outcomes. Head-worn displays (HWDs) can provide hands-free access to continuous vital sign information of patients in critical and acute care contexts and thus may reduce instances of unrecognized patient deterioration. OBJECTIVE: The purpose of the study is to conduct a systematic review of the literature to evaluate clinical, surrogate, and process outcomes when clinicians use HWDs for continuous patient vital sign monitoring. METHODS: The review was registered with PROSPERO (CRD42019119875) and followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. A literature search was conducted for articles published between January 1995 and June 2020 using the following databases: PubMed, Embase, CINAHL, PsycINFO, and Web of Science. Overall, 2 reviewers independently screened titles and abstracts and then assessed the full text of the articles. Original research articles that evaluated the clinical, surrogate, or process outcomes of head-mounted displays for continuous vital sign monitoring in critical care or acute care contexts were included. RESULTS: Of the 214 records obtained, 15 (7%) articles met the predefined criteria and were included in this review. Of the 15 studies, 7 (47%) took place in a clinical context, whereas the remainder took place in a simulation environment. In 100% (7/7) of the studies that evaluated gaze behavior, changes were found in gaze direction with HWDs. Change detection improvements were found in 67% (2/3) of the studies evaluating changes in the participants' ability to detect changes in vital signs. Of the 10 studies assessing the ease of use of the HWD, most participants of 7 (70%) studies reported that the HWD was easy to use. In all 6 studies in which participants were asked if they would consider using the HWD in their practice, most participants responded positively, but they often suggested improvements on the HWD hardware or display design. Of the 7 studies conducted in clinical contexts, none reported any clinical outcomes. CONCLUSIONS: Although there is limited and sometimes conflicting evidence about the benefits of HWDs from certain surrogate and process outcomes, evidence for clinical outcomes is lacking. Recommendations are to employ user-centered design when developing HWDs, perform longitudinal studies, and seek clinical outcomes. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42019119875; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=119875.

Spearcon compression levels influence the gap in comprehension between untrained and trained listeners.

Auditory alarms in hospitals are ambiguous and do not provide enough information to support doctors and nurses' awareness of patient events. A potential alternative is the use of short segments of time-compressed speech, or spearcons. However, sometimes it might be desirable for patients to understand spearcons and sometimes not. We used reverse hierarchy theory to hypothesize that there will be a degree of compression where spearcons are intelligible for trained listeners but not for untrained listeners. In Experiment 1, spearcons were compressed to either 20% or 25% of their original duration. Their intelligibility was very high for trained participants, but also quite high for untrained participants. In Experiment 2 each word within each spearcon was compressed to a different degree based on the results of Experiment 1. This technique was effective in creating the desired difference in spearcon intelligibility between trained and untrained listeners. An implication of these results is that manipulating the degree of compression of spearcons "by word" can increase the effect of training so that untrained listeners reliably do not understand the content of the spearcons. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Evaluation of an enhanced pulse oximeter auditory display: a simulaion study.

BACKGROUND: We compared anaesthetists' ability to identify haemoglobin oxygen saturation (SpO2) levels using two auditory displays: one based on a standard pulse oximeter display (varying pitch plus alarm) and the other enhanced with additional sound properties (varying pitch plus tremolo and acoustic brightness) to differentiate SpO2 ranges. METHODS: In a counter-balanced crossover study in a simulator, 20 experienced anaesthetists supervised a junior colleague (an actor) managing two airway surgery scenarios: once while using the enhanced auditory display and once while using a standard auditory display. Participants were distracted with other tasks such as paperwork and workplace interruptions, but were required to identify when SpO2 transitioned between pre-set ranges (target, low, critical) and when other vital signs transitioned out of a target range. They also identified the range once a transition had occurred. Visual displays were available for all monitored vital signs, but the numerical value for SpO2 was excluded. RESULTS: Participants were more accurate and faster at detecting transitions to and from the target SpO2 range when using the enhanced display (100.0%, 3.3 s) than when using the standard display plus alarm (73.2%, 27.4 s) (P<0.001 and P=0.004, respectively). They were also more accurate at identifying the SpO2 range once a transition had occurred when using the enhanced display (100.0%) than when using the standard display plus alarm (57.1%; P<0.001). CONCLUSIONS: The enhanced auditory display helps anaesthetists judge SpO2 levels more effectively than current auditory displays and may facilitate 'eyes-free' monitoring.

Smooth or Stepped? Laboratory Comparison of Enhanced Sonifications for Monitoring Patient Oxygen Saturation.

BACKGROUND: The pulse oximeter (PO) provides anesthesiologists with continuous visual and auditory information about a patient's oxygen saturation (SpO2). However, anesthesiologists' attention is often diverted from visual displays, and clinicians may inaccurately judge SpO2 values when relying on conventional PO auditory tones. We tested whether participants could identify SpO2 value (e.g., "97%") better with acoustic enhancements that identified three discrete clinical ranges by either changing abruptly at two threshold values (stepped-effects) or changing incrementally with each percentage value of SpO2 (smooth-effects). METHOD: In all, 79 nonclinicians participated in a between-subjects experiment that compared performance of participants using the stepped-effects display with those who used the smooth-effects display. In both conditions, participants heard sequences of 72 tones whose pitch directly correlated to SpO2 value, and whose value could change incrementally. Primary outcome was percentage of responses that correctly identified the absolute SpO2 percentage, ±1, of the last pulse tone in each sequence. RESULTS: Participants using the stepped-effects auditory tones identified absolute SpO2 percentage more accurately (M = 53.7%) than participants using the smooth-effects tones (M = 47.9%, p = .038). Identification of range and detection of transitions between ranges showed even stronger advantages for the stepped-effects display (p < .005). CONCLUSION: The stepped-effects display has more pronounced auditory cues at SpO2 range transitions, from which participants can better infer absolute SpO2 values. Further development of a smooth-effects display for this purpose is not necessary.