Monitoring calls and warning signs and symptoms.

The World Health Organization recommends remote monitoring and self-administered pulse oximetry to identify silent hypoxia and the need for medical intervention in non-hospitalized high-risk COVID-19 patients. These interventions have been evaluated previously, but evidence is needed to determine the impact on morbidity and mortality, particularly in lower- and middle-income countries. A prospective, pragmatic, open-label trial was conducted in Tegucigalpa and Comayagüela, Honduras to evaluate the impact of self-administered pulse oximetry to reduce morbidity and mortality among non-hospitalized patients at high risk of adverse COVID-19 outcomes enrolled in a remote monitoring program. Participants were cluster-randomized, with temporal clustering by day, to remote monitoring plus self-administered pulse oximetry versus remote monitoring alone. Participants received daily calls to assess for high-risk clinical features, including hypoxia (SpO2 ≤ 94%) in the pulse oximetry arm. All participants reporting high risk symptoms were referred for in-person evaluation. ClinicalTrials.gov, ID number NCT04886414. Between March 30, 2022 and January 24, 2023, 1,821 participants met the intention to treat analysis criteria; 925 were randomized to remote monitoring and 897 to remote monitoring with pulse oximetry. Nearly 99% of participants reported receiving one or more COVID-19 vaccine doses, and 90.2% three or more doses, with similar coverage across arms. Pulse oximetry arm participants were more likely to be referred for clinical evaluation (OR 1.60 [95% CI 1.09 – 2.46], p = 0.018), but not more likely to be hospitalized (OR 1.55 [95% CI 0.55 – 4.37, p = 0.401]. One participant died, two required intensive care, and none required ventilation. Findings suggest that self-administered pulse oximetry increased referral for additional care but did not influence hospitalization rates among a high-risk, highly vaccinated, population with low incidence of severe COVID-19. Given infrequent progression to severe COVID-19, the relationship between the intervention and mortality, mechanical ventilation, or admission to intensive care was not assessed.