Practices and Perceptions of Infectious Diseases and Critical Care Clinicians Regarding Aerosolized Antimicrobial Therapy in the State of Qatar: A Multicenter Cross-Sectional Study.

Background/Objectives: The prescription of aerosolized antimicrobial agents for lower respiratory tract infections varies significantly among clinicians. This study investigated the practices and perceptions of clinicians regarding aerosolized antimicrobial therapy. Methods: A cross-sectional study was conducted among infectious diseases (ID) and critical care clinicians (physicians and clinical pharmacists) in eight acute care hospitals in Qatar using a validated and pretested self-administered online questionnaire. Data was collected between September and October 2025, and analyzed using the Statistical Package for the Social Sciences (SPSS). Results: The majority of the respondents were physicians (70.5%), and about one-third (31.8%) had more than 15 years of work experience. A vast majority (97.7%) had previously prescribed or recommended aerosolized antimicrobial agents. Some respondents (34.1%) reported using aerosolized antimicrobial agents at least once every three months. The indications for aerosolized antimicrobial prescribing were for the treatment of bacterial infections (86.4%) and prophylaxis against bacterial infections (38.6%). Aerosolized antimicrobials were used for the treatment of ventilator-associated pneumonia (68.2%), cystic fibrosis (61.4%) and ventilator-associated tracheobronchitis (34.1%). Gentamicin (88.6%) and colistin (72.7%) were the most frequently used aerosolized antimicrobial agents. The majority (88.6%) of the respondents combined aerosolized antimicrobial agents with systemic antimicrobial agents, 65.9% of whom combined different antimicrobials for aerosolized and systemic routes. Pseudomonas aeruginosa (97.7%) and Acinetobacter baumannii (56.8%) were the most common microorganisms treated with aerosolized antimicrobial agents. Most respondents (61.4%) did not provide pre-treatment prior to aerosolized antimicrobial therapy. However, 38.6% used bronchodilators for pre-treatment. Bronchospasm (79.5%) and hypoxemia (20.5%) were the adverse effects reported by the respondents. Some respondents (40.9%) strongly agreed/agreed that aerosolized antimicrobial therapy improves clinical and microbial cure rates. While 81.8% strongly agreed/agreed that aerosolized antimicrobial therapy reduces systemic toxicity. Practices and perceptions varied significantly between ID and critical care specialties, and between physicians and pharmacists. Conclusions: Clinicians need training on aerosolized antimicrobial therapy for lower respiratory tract infections. Immunosuppression, renal function and infections due to multidrug-resistant organisms were reported by clinicians as factors that influenced their decision to use aerosolized antimicrobial therapy. A protocol for the administration of aerosolized antimicrobial therapy is recommended.