The purpose of this study was to determine the effect of aerosolized colistin on to ventilated patients with carbapenem-resistant gram negative bacteria pneumonia. We hypothesize that adjunct aerosolized colistin, which achieve high drug concentrations in the airway, would more effectively treat the penumbra.

To treat respiratory infection of patients with mechanical ventilation, greater systemic antibiotic dose is required through the patient's venous injection. In this trial, patients with arbapenem-resistant gram negative bacteria pneumonia (CRGNB)were assigned to adjunct aerosolized colistin delivered by a jet nebulizer or a vibrating mesh nebulizer comparing to or standard intravenous injection by a randomizing protocol.

Need for a systemic antibiotic was determined by the clinical physician. Comparisons were made between standard care and study drug for their effects on bacteria eradiation, incidence of nephrotoxicity, and oxygenation.

Inclusion Criteria:

• Patients received invasive mechanical ventilation >48 hours
• Diagnosed with pneumonia caused by carbapenem resistance gram negative bacteria

Exclusion Criteria:

• pregnant or lactating women
• receiving colistin > 3 days
• recurrent pneumonia caused by carbapenem resistance gram negative bacteria
• allergy to colistin or polymyxin B drugs
• immunocompromised, defined as neutropenia ANC<500 cells/ul
• HIV positive
• received chemotherapy with 3 months
• renal function deficiency (creatinine clearance < 30 ml/min)