Comparison of Standard and Enhanced Pulse Oximeter Auditory Displays of Oxygen Saturation: A Laboratory Study With Clinician and Nonclinician Participants

Abstract

BACKGROUND: When engaged in visually demanding tasks, anesthesiologists depend on the auditory display of the pulse oximeter (PO) to provide information about patients’ oxygen saturation (Spo 2). Current auditory displays are not always effective at providing Spo 2 information. In this laboratory study, clinician and nonclinician participants identified Spo 2 parameters using either a standard auditory display or an auditory display enhanced with additional acoustic properties while performing distractor tasks and in the presence of background noise. METHODS: In a counterbalanced crossover design, specialist or trainee anesthesiologists (n = 25) and nonclinician participants (n = 28) identified Spo 2 parameters using standard and enhanced PO auditory displays. Participants performed 2 distractor tasks: (1) arithmetic verification and (2) keyword detection. Simulated background operating room noise played throughout the experiment. Primary outcomes were accuracies to (1) detect transitions to and from an Spo 2 target range and (2) identify Spo 2 range (target, low, or critical). Secondary outcomes included participants’ latency to detect target transitions, accuracy to identify absolute Spo 2 values, accuracy and latency of distractor tasks, and subjective judgments about tasks. RESULTS: Participants were more accurate at detecting target transitions using the enhanced display (87%) than the standard display (57%; odds ratio, 7.3 [95% confidence interval {CI}, 4.4–12.3]; P < .001). Participants were also more accurate at identifying Spo 2 range using the enhanced display (86%) than the standard display (76%; odds ratio, 2.7 [95% CI, 1.6–4.6]; P < .001). Secondary outcome analyses indicated that there were no differences in performance between clinicians and nonclinicians for target transition detection accuracy and latency, Spo 2 range identification accuracy, or absolute Spo 2 value identification. CONCLUSIONS: The enhanced auditory display supports more accurate detection of target transitions and identification of Spo 2 range for both clinicians and nonclinicians. Despite their previous experience using PO auditory displays, clinicians in this laboratory study were no more accurate in any Spo 2 outcomes than nonclinician participants.

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

“…We chose not to compare the stepped and smooth-effects sonifications with the conventional PO sonification as a control for two reasons. First, as already indicated, stepped-effects PO sonifications have proven to be significantly better than conventional PO sonification in several prior studies (Deschamps et al, 2016; Paterson et al, 2017; Paterson et al, in press; Paterson et al, 2016; Zestic et al, 2019). Second, if the smooth-effects sonification supports better performance than the stepped-effects sonification in the present study, then it would also support better performance than the conventional PO sonification.…”

“…In the above studies, participants were also more accurate at identifying the absolute SpO 2 value (±1%) at the end of each scenario when they used the stepped sonification (Paterson et al, in press; Paterson et al, 2017). However, despite the substantial superiority of the stepped-effects sonification over the conventional sonification for identifying SpO 2 ranges, accuracy for identifying absolute SpO 2 values still only reached 65% with the stepped sonification in Paterson et al (2017) and 67% in Paterson et al (in press). This may have been because the only acoustic property that varied within each SpO 2 range was pitch.…”

“…Paterson et al (2016) added tremolo to the low SpO 2 range and both tremolo and brightness to the critical SpO 2 range (see center image of Figure 1) and again found that participants performed significantly better with the stepped sounds. Even when participants performed a demanding ongoing task in the presence of background noise, participants identified SpO 2 range significantly better with the stepped sonification than with a conventional sonification (Paterson et al, 2017; Paterson, Sanderson, Brecknell, Paterson, & Loeb, in press).…”

A Novel Auditory Display for Neonatal Resuscitation: Laboratory Studies Simulating Pulse Oximetry in the First 10 Minutes After Birth

“…This was acceptable given that the studies tested perception and classification performance only (Rasmussen, Pejtersen, & Goodstein, 1994;Sanderson & Burns, 2017). Similar studies show no performance differences between clinicians and nonclinicians (Paterson, Sanderson, Brecknell, Paterson, & Loeb, 2018). Future research will move toward effectiveness trials, requiring the participation of clinicians.…”

Evaluation of an enhanced pulse oximeter auditory display: a simulation study

“…9 Further research shows that anaesthetists have difficulty identifying changes in SpO 2 from 97% to 96% (in both directions) and difficulty identifying absolute SpO 2 levels using a pitch-only display. 10 Moreover, as visual attention load increases and noise level rises, anaesthetists become less able to identify a change from 99% to 98% saturation when listening to a Philips patient monitor (Model MP70; Philips Electronics, Amsterdam, The Netherlands). 11 Our group has added the sound dimensions of tremolo and acoustic brightness to the varying pitch display to distinguish SpO 2 ranges for adult patients 10,12,13 and neonates.…”