Prophylactic Antibiotics Delivered Via the Respiratory Tract to Reduce Ventilator-Associated Pneumonia: A Systematic Review, Network Meta-Analysis, and Trial Sequential Analysis of Randomized Controlled Trials

Potentially effective antimicrobial treatment for pneumonia caused by isolates of carbapenem-resistant and extensively drug-resistant Acinetobacter baumannii complex species: what can we expect in the future?

INTRODUCTION

Acinetobacter baumannii complex (Abc) is currently a significant cause of difficult-to-treat pneumonia. Due to the high prevalence rates of carbapenem- and extensively drug-resistant (CR, XDR) phenotypes, limited antibiotic options are available for the effective treatment of pneumonia caused by CR/XDR-Abc.

AREAS COVERED

In vitro susceptibility data, relevant pharmacokinetic profiles (especially the penetration ratios from plasma into epithelial-lining fluid), and pharmacodynamic indices of key antibiotics against CR/XDR-Abc are reviewed.

EXPERT OPINION

Doubling the routine intravenous maintenance dosages of conventional tigecycline (100 mg every 12 h) and minocycline (200 mg every 12 h) might be recommended for the effective treatment of pneumonia caused by CR/XDR-Abc. Nebulized polymyxin E, novel parenteral rifabutin BV100, and new polymyxin derivatives (SPR206, MRX-8, and QPX9003) could be considered supplementary combination options with other antibiotic classes. Regarding other novel antibiotics, the potency of sulbactam-durlobactam (1 g/1 g infused over 3 h every 6 h intravenously) combined with imipenem-cilastatin, and the β-lactamase inhibitor xeruborbactam, is promising. Continuous infusion of full-dose cefiderocol is likely an effective treatment regimen for CR/XDR-Abc pneumonia. Zosurabalpin exhibits potent anti-CR/XDR-Abc activity in vitro, but its practical use in clinical therapy remains to be evaluated. The clinical application of antimicrobial peptides and bacteriophages requires validation.

Inhaled antibiotics for treating pneumonia in invasively ventilated patients in intensive care unit: a meta-analysis of randomized clinical trials with trial sequential analysis

BACKGROUND

The use of inhaled antibiotics for treating pneumonia in invasively ventilated patients offers a direct approach, allowing for high local concentrations of the drug in the lower respiratory tract while simultaneously reducing systemic toxicity. However, the real efficacy and safety of nebulized antibiotics remain unclear. The aim of the present is to assess among critically adult patients with pneumonia and invasive ventilation, whether receiving adjuvant inhaled antibiotics improves the rate of microbiological eradication.

METHODS

A comprehensive literature search of randomized clinical trials (RCTs) was conducted (from inception until September 20, 2024, PROSPERO-CRD592906) across Medline, Embase, and Scopus. Randomized controlled trials, enrolling intensive care units (ICU) patients with pneumonia and comparing nebulized antimicrobial therapy (inhaled group) with intravenous antimicrobial treatment or intravenous antimicrobial therapy plus inhaled placebo (control group), were included. The primary outcome was the rate of microbiological eradication after treatment. Secondary outcomes were the rate of clinical recovery, the incidence of drug-related adverse events, ICU and hospital mortality. A qualitative analysis was conducted according to the GRADE framework. Data were pooled using an odds-ratio analysis. The heterogeneity and reliability of our results were evaluated using the I2-statistic and trial sequential analysis (TSA), respectively.

RESULTS

A total of 11 RCTs (1472 patients) met the inclusion criteria. Compared to controls, the use of adjuvant inhaled antibiotics determined a greater rate of microbiological eradication (OR 2.63, 95% CI 1.36-5.09; low certainty of evidence). The TSA confirmed the reliability of our primary outcome. Moreover, nebulized antibiotics increased the risk of bronchospasm (OR 3.15, 95% CI 1.33-7.47; high evidence), while nephrotoxicity, clinical recovery, ICU and hospital survival (either in the case of pneumonia caused by MDR bacteria or not) were not different between groups.

CONCLUSIONS

In conclusion, compared to the sole intravenous therapy, the use of adjuvant inhaled antibiotics for treatment of pneumonia in invasively ventilated critically ill patients was associated with a greater incidence of microbiological eradication (low GRADE and high risk of publication bias), but not with clinical recovery and survival.

Aerosolized Antibiotic Therapy in Mechanically Ventilated Patients

Delivering antibiotics directly to the respiratory tract through inhalation to address lung infections has garnered clinical and scientific interest for decades, given the potential favorable pharmacokinetic profile of this administration route. Among critically ill patients, the burden of healthcare-associated pulmonary infections particularly drove continued interest in delivering inhaled antibiotics to intubated patients. We present a concise overview of the existing rationale and evidence and provide guidance for implementing inhaled antibiotics among ventilated critically ill patients, emphasizing insights from recent literature.