Abstract Rationale Noninvasive respiratory support (NIRS), including noninvasive positive pressure ventilation (NIPPV) or high flow nasal oxygen (HFNO), improves gas exchange in acute hypercapnic respiratory failure. However, NIRS failure requiring intubation is associated with increased mortality. Continuous monitoring to guide titration and detect early failure is essential. Arterial blood gas (ABG) measurement of the partial pressure of carbon dioxide (PaCO2) remains the gold standard for assessing ventilation adequacy but is invasive and resource dependent. Transcutaneous carbon dioxide (tCO2) monitoring offers a noninvasive alternative that enables continuous tracking of CO2 trends without repeated blood draws. We hypothesized that real-time tCO2 assessment could optimize NIRS titration, reduce unnecessary ABGs, and improve process outcomes such as length of stay (LOS), time to intubation, and NIRS titration. Methods This hybrid implementation-effectiveness trial was embedded into usual care. We describe the implementation process and interim evaluation. Adults with acute hypercapnic respiratory failure requiring NIRS were monitored with tCO2. Participating clinicians received education on device use. Baseline demographics, comorbidities, and clinical outcomes were collected and compared with a matched retrospective cohort treated without tCO2 monitoring. Clinician feedback on usability and clinical integration was gathered through anonymous surveys. An interim analysis after 20 prospective enrollments assessed implementation effectiveness and identified improvement strategies. Primary outcome included frequency of NIRS titration (changes between devices or settings). Secondary outcomes included total time on NIRS and number of ABGs performed. Results Seventeen of the 20 prospective patients were included in the interim analysis. Among 178 patients on NIRS from the medical ICU or ED between April-December 2024, 69 met inclusion criteria for comparison. Thirteen provider surveys were analyzed. No significant differences were observed between groups in demographics, LOS, NIRS titration, or blood gas frequency (Table). The retrospective cohort had higher APACHE II and Charlson Comorbidity Index scores, while the prospective group presented with more pronounced respiratory acidosis. Providers described tCO2 monitoring as easy to use and accurate but emphasized the need for additional education and clearer guidance for interpretation. Conclusion The interim analysis identified key areas to enhance implementation effectiveness of tCO2 monitoring. While quantitative outcomes showed no significant process differences, qualitative data revealed high acceptability and perceived utility—critical for adoption. Barriers included limited user familiarity, lack of standardized protocols, and variable workflow integration. Targeted education, workflow alignment, and feedback mechanisms may enhance fidelity and sustainability. Future phases will refine these strategies and evaluate their impact on clinical and patient-centered outcomes. This abstract is funded by: None
Mihalache et al. (Fri,) studied this question.