Evaluation of the Effectiveness of Adjunctive N-Acetylcysteine Nebulizer in Critically Ill Patients with COVID-19: A Pre-post Study

Abstract Background: The uncontrolled inflammatory immune response associated with SARS-CoV-2 can lead to cytokine storm and acute respiratory distress syndrome. N -Acetylcysteine (NAC) nebulizer therapy is being considered as a potential treatment option in coronavirus disease 2019 (COVID-19) patients due to its mucolytic, antioxidant, anti-inflammatory, and antiviral properties. However, the use of NAC in critically ill COVID-19 patients has not been extensively studied. Therefore, a study was conducted to evaluate the effectiveness of adjunctive NAC on respiratory function in critically ill patients with COVID-19. Materials and Methods: A pre-post retrospective study included critically ill patients with COVID-19 admitted to the intensive care units and received NAC nebulizers between March 2020 and July 2021. The primary outcome was to assess the PaO 2 /FiO 2 (P/F) ratio differences before and after NAC administration. Other outcomes were considered secondary, such as the positive end-expiratory pressure (PEEP), tidal volume, and invasive mechanical ventilation (MV) status. A paired t test or Wilcoxon signed-rank test was used based on the data distribution. A P value of <0.05 was considered statistically significant. Results: The results revealed that a total of 1081 critically ill patients with COVID-19 were screened during the study period, and only 44 were included. Most of the patients were male (75%) with a median age of 58 years (range = 48.5–76.5 years). Before NAC initiation, the median P/F ratio was 136.55 (with a range of 92.15–207.3), whereas 24 h post-initiation, it increased significantly to a median of 159.7 (with a range of 109.6–270.2; P = 0.02). In contrast, no statistically significant differences were observed in PEEP, tidal volume, and invasive MV status before and after NAC initiation. Conclusion: This study concludes that adjunctive NAC therapy in critically ill patients with COVID-19 was associated with improved P/F ratio 24 h:24-h post-initiation. This improvement occurred without significant differences observed in PEEP, tidal volume, and invasive MV status. However, it is essential to conduct randomized control trials to validate these findings and determine their clinical significance.