COMPARATIVE EFFECTIVENESS OF INHALED NITRIC OXIDE IN ARDS AND VIRAL PNEUMONIA WITH AND WITHOUT COVID-19

ABSTRACT

SESSION TITLE ECMO and ARDS in COVID-19 Infections SESSION TYPE Rapid Fire Original Inv PRESENTED ON 10/17/2022 1215 pm - 115 pm PURPOSE: Inhaled nitric oxide (iNO) is a potent vasodilator of pulmonary vasculature improving perfusion to ventilated alveoli in ARDS and other lung pathologies. During the pandemic, intensivists turned to iNO as “salvage” therapy in COVID-19 patients. Rationale was driven by vasodilatory effect and antiviral properties despite lack of evidence of clear benefit even in patients without COVID. We hypothesized that iNO would provide reduced increases in pulmonary perfusion and subsequent gas exchange improvement in COVID-19 patients due to extensive endothelial damage and coagulopathy throughout the pulmonary vasculature. METHODS: Our IRB exempt analysis examined patients hospitalized with and without COVID-19 from January 2020 to September 2021 who received at least 24h of invasive mechanical ventilation with iNO (15-20ppm). Effectiveness outcomes were PaO2/FIO2 ratio(PFR), PEEP/CPAP level, and PaCO2 serially measured and observed up to 24 hours prior to initiation of iNO and for up to 120h post iNO administration. Data were statistically controlled for age, sex, race, time to initiation of therapy and COVID-19 directed treatment. RESULTS: From January 2020 and September 2021, 42 patients were admitted to the ICU and received invasive mechanical ventilation and iNO. Results are sequenced as ARDS COVID-negative, ARDS COVID-positive, viral pneumonia COVID-negative, viral-pneumonia COVID-positive. Patient n = 8/14/6/14. Median age was 56/55/63/62 years. Demographics split 64-62% male vs 36-38% female in ARDS without/with COVID, 50%/83% male vs 50%/17% female in viral pneumonia without/with COVID. Racial distribution resulted 75%/93%/86%/83% White vs 25%/0%/17%/14% Black. Other races constituted less than 7% of patient total in any category. PFR delta from -24h to +120h post-iNO = +35/+35/+41/+22. PEEP/CPAP delta from -24h to +120h = -4/-1/-3/-2. PaCO2 delta mmHg from -24h to +120h = -21/-23/-9/-13. Median Hospital LOS = 26/26.5/17/19 days. Median ICU LOS = 15.8/19.0/13.8/17.6 days. Hospital mortality = 100% across all 4 subgroups. CONCLUSIONS: ARDS patients with or without COVID showed similar rates of PFR response to iNO, however viral pneumonia patients with COVID exhibited a blunted PFR response vs those without COVID. No statistically significant difference was observed with respect to PEEP/CPAP levels, PaCO2 mmHg, hospital or ICU LOS, or mortality. CLINICAL IMPLICATIONS Our findings suggest that the presence of COVID-19 did not significantly inhibit response to iNO in ARDS or other viral pneumonia patients. Further evaluation of other indirect markers of gas exchange could provide further evidence of responsiveness. DISCLOSURES No relevant relationships by Katherine Burns No relevant relationships by Karen Hamad No relevant relationships by Bobby Malik No relevant relationships by Richard Walo Jr No relevant relationships by Wilhelmine Wiese-Rometsch No relevant relationships by Stephanie Williams