It has long been known that many pulse oximeters function less accurately in patients with darker skin. Reasons for this observation are incompletely characterized and potentially enabled by limitations in existing regulatory oversight. Based on decades of experience and unpublished data, we believe it is feasible to fully characterize, in the public domain, the factors that contribute to missing clinically important hypoxemia in patients with darkly pigmented skin. Here we propose 5 priority areas of inquiry for the research community and actionable changes to current regulations that will help improve oximeter accuracy. We propose that leading regulatory agencies should immediately modify standards for measuring accuracy and precision of oximeter performance, analyzing and reporting performance outliers, diversifying study subject pools, thoughtfully defining skin pigmentation, reporting data transparently, and accounting for performance during low-perfusion states. These changes will help reduce bias in pulse oximeter performance and improve access to safe oximeters.

Background: One of the biggest barriers to accessing safe surgical and anesthetic care is lack of trained providers. Uganda has one of the largest deficits in anesthesia providers in the world, and though they are increasing in number, they remain concentrated in the capital city. Salary is an oft-cited barrier to rural job choice, yet the size and sources of anesthesia provider incomes are unclear, and so the potential income loss from taking a rural job is unknown. Additionally, while salary augmentation is a common policy proposal to increase rural job uptake, the relative importance of non-monetary job factors in job choice is also unknown. Methods: A survey on income sources and magnitude, and a Discrete Choice Experiment examining the relative importance of monetary and non-monetary factors in job choice, was administered to 37 and 47 physician anesthesiologists in Uganda, between May–June 2019. Results: No providers worked only at government jobs. Providers earned most of their total income from a non-government job (50% of income, 23% of working hours), but worked more hours at their government job (36% of income, and 44% of working hours). Providers felt the most important job attributes were the quality of the facility and scope of practice they could provide, and the presence of a colleague (33% and 32% overall relative importance). These were more important than salary and living conditions (14% and 12% importance). Conclusions: No providers accepted the salary from a government job alone, which was always augmented by other work. However, few providers worked only nongovernment jobs. Non-monetary incentives are powerful influencers of job preference, and may be leveraged as policy options to attract providers. Salary continues to be an important driver of job choice, and jobs with fewer income generating opportunities (e.g. private work in rural areas) are likely to need salary augmentation to attract providers.

(TCD) in healthy volunteers during profound hypocapnia and hypercapnia. METHODS: Ten healthy volunteers were monitored with a combination of TCD, UT-NIRS (c-FLOW, Ornim Medical), as well as heart rate, blood pressure, end-tidal Pco2 (PEtco2), end-tidal O2, and inspired O2. Inspired CO2 and minute ventilation were controlled to achieve 5 stable plateau goals of Etco2 at 15–20, 25–30, 35–40, 45–50, and 55–60 mm Hg, for a total of 7 measurements per subject. CBF was assessed at a steady state, with the TCD designated as the reference standard. The primary analysis was a linear mixed-effect model of TCD and UT-NIRS flow with PEtco2, which accounts for repeated measures. Receiver operating characteristic curves were determined for detection of changes in CBF. RESULTS: Hyperventilation (nadir PEtco2 17.1 ± 2.4) resulted in significantly decreased mean flow velocity of the middle cerebral artery from baseline (to 79% ± 22%), but not a consistent decrease in UT-NIRS cerebral flow velocity index (n = 10; 101% ± 6% of baseline). Hypercapnia (peak PEtco2 59.3 ± 3.3) resulted in a significant increase from baseline in both mean flow velocity of the middle cerebral artery (153% ± 25%) and UT-NIRS (119% ± 11%). Comparing slopes versus PEtco2 as a percent of baseline for the TCD (1.7% [1.5%–2%]) and UT-NIRS (0.4% [0.3%–0.5%]) shows that the UT-NIRS slope is significantly flatter, P < .0001. Area under the receiver operating characteristic curve was significantly higher for the TCD than for UT-NIRS, 0.97 (95% confidence interval, 0.92–0.99) versus 0.75 (95% confidence interval, 0.66–0.82). CONCLUSIONS: Our data indicate that UT-NIRS cerebral flow velocity index detects changes in CBF only during hypercarbia but not hypocarbia in healthy subjects and with much less sensitivity than TCD. Additional refinement and validation are needed before widespread clinical utilization of UT-NIRS....

Background: Some pulse oximeters perform worse in people with darker skin, and this may be due to inadequate diversity of skin pigment in device development study cohorts. Guidance is needed to accurately and equitably characterize skin pigment to ensure diversity in research cohorts. We tested multiple methods for characterizing skin pigment to assess comparability and impact on cohort diversity. Objectives: The objectives of this study were to assess reliability and comparability of common skin pigment measurement methods, compare findings from different anatomical sites and demonstrate that pigment cannot be assumed from US National Institutes for Health (NIH) race categories. Methods: We used three subjective methods [perceived Fitzpatrick (pFP) scale, Monk Skin Tone (MST) scale and Von Luschan (VL) scale] and two objective methods [Konica Minolta CM-700d spectrophotometer and Delfin Skin Color Catch (DSCC) colorimeter] for individual typology angle (ITA) across multiple measurement sites in adults. We calculated ΔE to estimate operator perceptibility thresholds for subjective methods and to determine reproducibility for objective methods. We used each method to categorize participants as ‘light, medium or dark’ and compared the impact of method selection on cohort diversity. Results: We studied 789 participants, with 33 856 assessments. The MST had the widest luminosity range, and the VL scale had the least discernible adjacent categories. With ‘dark’ defined as ITA < −30°, 14% of participants were categorized ‘dark’ as compared with 26% by pFP or 16% by MST. Approximately half of the ‘dark’ cohort had an ITA < −50°. With an ITA threshold < −50°, only 7% of the cohort was categorized as ‘dark'. When ‘Black or African American’ self-identification was used to define ‘dark’, 23% of the cohort was categorized as such. Each self-assigned NIH race category included a wide range of ITA and subjective scale categories. Both ITA and L* from the KM-700d and DSCC demonstrated strong correlation (ρ > 0.7). Conclusions: Common methods for skin pigment characterization, especially the use of race or subjective scales, have significant limitations. When applied to the same cohort, different methods yield significantly different results and some may overestimate diversity. Previously published ITA thresholds for defining ‘dark’ skin are too light and lead to under-representation of people with darker skin.

The rapid pace of the COVID-19 pandemic precluded traditional approaches to evaluating clinical research and guidelines. We highlight notable successes and pitfalls of clinicians’ new approaches to managing evidence amidst an unprecedented crisis. In “Era 1” (early 2020), clinicians relied on anecdote and social media, which democratized conversations on guidelines, but also led clinicians astray. “Era 2” (approximately late 2020 to early 2021) saw preprints that accelerated new interventions but suffered from a surfeit of poor-quality data. In the current era, clinicians consolidate the evidentiary gains of Era 2 with living, online clinical guidelines, but the public suffers from misinformation. The COVID-19 pandemic is a laboratory on how clinicians adapt to an absence of clinical guidance amidst an informational and healthcare crisis. Challenges remain as we integrate new approaches to innovations made in the traditional guideline process to confront both the long tail of COVID-19 and future pandemics.

Background Some pulse oximeters perform worse in people with darker skin, and this may be due to inadequate diversity of skin pigment in device development study cohorts. Guidance is needed to accurately and equitably characterize skin pigment to ensure diversity in research cohorts. We tested multiple methods for characterizing skin pigment to assess comparability and impact on cohort diversity. Objectives Assess reliability and comparability of common skin pigment measurement methods Compare findings from different anatomical sites Demonstrate that pigment cannot be assumed from US National Institutes for Health (NIH) race categories Methods We used three subjective methods (perceived Fitzpatrick pFP, Monk Skin Tone MST and Von Luschan VL) and two objective methods (Konica Minolta CM-700d spectrophotometer and Delfin Skin Color Catch DSCC colorimeter) for individual typology angle (ITA), across multiple measurement sites in adults. We calculated ΔE to estimate operator perceptibility thresholds for subjective methods and to determine reproducibility for objective methods. We used each method to categorize participants as ‘light, medium, or dark’ and compared the impact of method selection on cohort diversity. Results We studied 789 participants, with 33,856 assessments. The MST had the widest luminosity range, and VL had the least discernible adjacent categories. With ‘dark’ defined as ITA <-30°, 14% of participants were categorized ‘dark’ as compared to 26% by pFP or 16% by MST. Approximately half of the ‘dark’ cohort had an ITA <-50°. With an ITA threshold <-50°, only 7% of the cohort was categorized as ‘dark.’ When ‘Black or African American’ self-identification was used to define ‘dark’, 23% of the cohort was categorized as such. Each self-assigned NIH race category included a wide range of ITA and subjective scale categories. Both ITA and L* from the KM-700d and DSCC demonstrated strong correlation (⍴ > 0.7). Conclusion Common methods for skin pigment characterization, especially the use of race or subjective scales, have significant limitations. When applied to the same cohort, different methods yield significantly different results, and some may overestimate diversity. Previously published ITA thresholds for defining ‘dark’ skin are too light and lead to underrepresentation of people with darker skin.