The use of successive systolic differences in photoplethysmographic (PPG) signals for respiratory rate estimation.

Most PPG-based methods for extracting the respiratory rate (RR) rely on changes in the PPG signal's amplitude, baseline, or frequency. However, several other parameters may provide more valuable information for accurate RR computation. In this study, we explored the capabilities of the respiratory-induced variations in successive systolic differences (RISSDV) of PPG signals to estimate RR. We partitioned fifty-three publicly available recordings into eight 1-min segments and identified peaks and troughs of the PPG signals to quantify respiratory-induced variations in amplitude (RIAV), baseline (RIIV), frequency (RIFV), and peak-to-peak amplitude differences (RISSDV). RR values were extracted by determining the peak frequency of the power spectral density of the four variations and the reference respiratory signal. We assessed each feature's performance by computing the root-mean-squared (RMSE) and mean absolute errors (MAE). RISSDV errors were significantly lower than those of RIAV (RMSE and MAE: p < 0.001), RIIV (RMSE: p < 0.01; MAE p < 0.05), and RIFV (RMSE and MAE: p < 0.001), and it appeared less sensitive to absent or missed PPG pulses than respiratory-induced frequency variations. Further research is necessary to extrapolate these findings to subjects under ambulatory rather than stationary conditions, including pediatric and neonatal populations.

Capturing the Experiences and Challenges of Emerging Adults in College During the COVID-19 Pandemic.

Emerging adulthood (ages 18-30 years) coincides with "aging out" of pediatric care. As a result, combined internal medicine and pediatrics (Med-Peds) providers are tasked with promoting the health and well-being of this population during and post-coronavirus disease 2019 (COVID-19). In order to inform the response efforts, we aimed to capture emerging adults' COVID-19 experiences and challenges during a two-week period of the pandemic in June 2020. We administered items from the California Health Interview Survey and an open-ended qualitative item via Qualtrics to 242 diverse emerging adults enrolled in a large US public university (mean age = 20.10, SD = 1.26). More than 90% of all students reported that they or their families or close friends experienced difficulties coping with the stressors and challenges presented by COVID-19. Almost half experienced financial difficulties and more than three-fourths experienced household disruptions during the pandemic. Qualitative findings underscored that these challenges were compounded by mental health and broader social issues. Recommendations for Med-Peds providers are provided to promote emerging adulthood health during and post-pandemic.