ARTERIAL PACO₂ AS A PREDICTOR OF MORTALITY AND VENTILATOR SUPPORT IN COPD PATIENTS WITH COVID-19

SESSION TITLE: Novel Biomarkers of Asthma and COPD Severity SESSION TYPE: Rapid Fire Original Inv PRESENTED ON: 10/09/2023 12:00 pm - 12:45 pm PURPOSE: Respiratory failure is a significant concern for COPD patients who develop COVID-19, as it has been associated with increased mortality. Given that COVID-19 has been linked to increased respiratory rate and hypocapnia, it remains unknown what threshold of arterial blood carbon dioxide tension (PaCO2) is predictive of adverse outcomes in COPD patients. To address this gap, our study aimed to determine the PaCO2 at initial presentation that predicts adverse outcomes in hospitalized COPD patients with COVID-19. METHODS: This study examined 27,810 patients from the Cleveland Clinic COVID-19 registry between March 8th and September 16th, 2020 in Ohio and Florida. Of these, 1,683 COPD patients were admitted to the hospital and had an arterial blood gas (ABG) performed within one day of a positive COVID-19 test. Youden’s criteria determined the optimal cut point that predicted mortality based on PaCO2 in mm Hg. Multivariate logistic regression was performed based on the cut point (adjusted for age, BMI, gender, and race). RESULTS: Of the 1,643 COPD patients who tested positive for COVID-19, 11.9% (n=196) had PaCO2>30. Those with PaCO2>30 were more likely to be admitted to the ICU versus those with PaCO2≤30 (30.1% for those PaCO2>30, 9.0% for those PaCO2≤30, p<0.001). They were also more likely to require mechanical ventilation (13.8% for PaCO2>30, 2.1% for PaCO2≤30, p<0.001), and had higher mortality (22.7% for PaCO2>30, 7.2% for PaCO2≤30, p<0.001). The receiver operating curve demonstrated a c-statistic of 0.70 (95% Confidence Interval: 0.65, 0.76). Multivariate logistic regression analysis demonstrated that PaCO2>30 was associated with increased odds for mortality (adj OR 3.10, 95% CI: 2.02-4.73). CONCLUSIONS: PaCO2 >30mmHg provides the best discrimination for increased risk for mortality and need for mechanical ventilation in hospitalized COPD patients with COVID-19. CLINICAL IMPLICATIONS: This subgroup of patients who present with PaCO2>30 may require additional vigilance. DISCLOSURES: No relevant relationships by Amy Attaway No relevant relationships by Umur Hatipoglu No relevant relationships by Uddalak MAJUMDAR No relevant relationships by Purnadeo Persaud No relevant relationships by Joe Zein