Improving fidelity of implementation of self-administered pulse oximetry and remote patient monitoring in Honduras during the COVID-19 pandemic.

During the COVID-19 pandemic, Honduras' Secretariat of Health was eager to understand whether self-administered pulse oximetry could improve clinical outcomes of high-risk COVID-19 patients. While these interventions show promise for expanding healthcare access in lower- and middle-income countries, evidence about contextual implementation fidelity and effectiveness remains limited. We conducted a retrospective fidelity of implementation analysis of phone-based patient monitoring with or without self-administered pulse oximetry in Tegucigalpa and Comayagüela, Honduras. Using Carroll's Conceptual Framework for Implementation Fidelity, we analyzed adherence (content, coverage, frequency, duration), delivery quality, participant responsiveness, and implementation strategies through trial data, acceptability assessments, and implementation documentation. The intervention achieved high fidelity: 98.9% coverage (1,821/1,841 eligible patients), 97.7% daily monitoring call completion, and 97.7% pulse oximeter utilization. Implementation strategies included culturally-adapted education materials, communication styles tailored to participants, and multi-disciplinary team engagement. Participant satisfaction was 99.2%, with minimal withdrawal (0.3%) and loss to follow-up (2.0%). However, only 28% of participants sought additional care when referred for warning signs. Unexpected benefits included reported positive impacts on participants' mental health during isolation. This analysis demonstrates that remote patient monitoring and self-administered pulse oximetry implementation can achieve high fidelity in a lower-middle-income setting, including during a health emergency and where such interventions are novel. This challenges concerns about technology access and adoption in resource-limited environments. Future research should focus on hybrid effectiveness-implementation trials and strategies to improve referral adherence. These findings suggest that expanding implementation of these approaches may enhance healthcare access during emergencies and routine circumstances.