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Contactless vital signs (VS) measurement with video photoplethysmography (vPPG), motion analysis (MA), and passive infrared thermometry (pIR) has shown promise.To compare conventional (contact-based) and experimental contactless VS measurement approaches for emergency department (ED) walk-in triage in pandemic conditions.Patients' heart rates (HR), respiratory rates (RR), and temperatures were measured with cardiorespiratory monitor and vPPG, manual count and MA, and contact thermometers and pIR, respectively.There were 475 walk-in ED patients studied (95% of eligible). Subjects were 35.2 ± 20.8 years old (range 4 days‒95 years); 52% female, 0.2% transgender; had Fitzpatrick skin type of 2.3 ± 1.4 (range 1‒6), Emergency Severity Index of 3.0 ± 0.6 (range 2‒5), and contact temperature of 36.83°C (range 35.89-39.4°C) (98.3°F [96.6‒103°F]). Pediatric HR and RR data were excluded from analysis due to research challenges associated with pandemic workflow. For a 30-s, unprimed "Triage" window in 377 adult patients, vPPG-MA acquired 377 (100%) HR measurements featuring a mean difference with cardiorespiratory monitor HR of 5.9 ± 12.8 beats/min (R = 0.6833) and 252 (66.8%) RR measurements featuring a mean difference with manual RR of -0.4 ± 2.6 beats/min (R = 0.8128). Subjects' Emergency Severity Index components based on conventional VS and contactless VS matched for 83.8% (HR) and 89.3% (RR). Filtering out vPPG-MA measurements with low algorithmic confidence reduced VS acquired while improving correlation with conventional measurements. The mean difference between contact and pIR temperatures was 0.83 ± 0.67°C (range -1.16-3.5°C) (1.5 ± 1.2°F [range -2.1-6.3°F]); pIR fever detection improved with post hoc adjustment for mean bias.Contactless VS acquisition demonstrated good agreement with contact methods during adult walk-in ED patient triage in pandemic conditions; clinical applications will need further study.

Objective: Investigators conducted pilot sessions in live Emergency Department (ED) settings to prepare for formal comparative study of contact and experimental non-contact vital signs (VS) measurement devices. Methods: Contact-based cardiorespiratory monitors (CM) and video photoplethysmography (vPPG) measured heart rates (HR); contact thermometers and passive infrared thermography (pIR) obtained core and surface temperatures. Subject VS data comprised two 25-min CM and vPPG recordings (initial unprimed “Triage Check” window; four 1-min “Full Check” windows; 20min of “Resting” intervals) and temperature measurements. Results: Forty-eight of 102 approached patients participated: at least 5 subjects each in 0-12mo, 1-5y, 6-12y, 13-17y age-groups, and at least 2 subjects each in 18-29y, 30-39y, 40-49y, 50-59y, 60-69y, 70-79y, 80+y age-groups. Subjects were 40.4% female with median Fitzpatrick skin type of 3.0 (interquartile range 1-3: 2.0-5.0), ESI score of 3.0 (2.0-3.0), and core temperature of 98.6°F (97.9-99.1°F). Twelve subjects were excluded from vPPG analysis due to inadequate lighting, excessive motion, and/or datastream loss. From the remaining 36 subjects with median HR CM of 78.2bpm (69.8-94.8bpm), vPPG measured median HR vPPG of 75.0bpm (68.3-93.0bpm) from 170 (70.5%) of 241 possible Full Check windows; the median difference between HR CM and HR vPPG was 0.6bpm (-0.2-2.3bpm). All Emergency Severity Index (ESI) HR components for 34 subjects with Triage Check HR vPPG measurements matched CM-based ESI HR components. Median differences between contact and pIR temperatures ranged from −5.4°F to −4.4°F. Conclusion: vPPG and pIR devices experimentally measured select live VS with promising results. Significance: Pilot data and protocol testing set the groundwork for full-scale ED vPPG-pIR investigation.

Accurate non-contact acquisition of patient vital signs will advance emergency care. In order to assess promising candidate technologies., an observational study was conducted with healthy volunteers to test two hypotheses: 1. Video photoplethysmography and motion analysis (vPPG-MA) and infrared thermography (IR) will accurately and concurrently measure heart rate (HR) and respiratory rate (RR)., and body temperature., respectively. 2. Non-contact approaches will exhibit comparable and reliable performance against standard contact cardiorespiratory monitors (CM). HR and RR were measured with CM and vPPG-MA; core and surface temperatures were obtained using oral thermometry and two IR cameras., respectively. Subjects were videorecorded at rest; during sustained exercise at 50%., 60%., and 70% of age-predicted maximum HR; and 1., 3., and 5 min post-exertion. vPPG-MA HR and RR measurements were calculated for video segments corresponding to ED use-cases: Triage (unprimed) 30s check., Routine 30s check, Abbreviated “Spot” 10s check., and Full 60s check. Descriptive statistics and Bland-Altman analyses were performed on vPPG-MA and IR measurements against synchronous CM measurements. Thirty volunteers exhibited a HR range of 43-146bpm., a RR range of 8-29bpm., and an oral temperature range of 96.2-99.5°F on CM. vPPG-MA obtained 972 (98.2% of scheduled) HR and 591 (98.5%) RR measurements; mean differences between Full 60s vPPG-MA and CM were −0.9±5.5bpm (-0.9±5.3%; 95% CI: −11.6–9.8bpm) for HR, and 0.9±3.1bpm (4.8±17.6%; −5.1–6.9bpm) for RR; other video segments performed similarly. IR acquired temperatures ~4°F lower than oral thermometers. vPPG-MA and IR thermography successfully measured select vital signs concurrently. vPPG-MA‘s observed level of agreement with CM, along with temperature offsets identified for IR-based thermometry., have set the foundation for live ED clinical studies.