ObjectiveTo evaluate the effectiveness and safety of nebulized amikacin for the treatment of ventilator-associated pneumonia (VAP) caused by gram-negative bacilli. MethodsFrom January 2010 to December 2013,a total of 120 patients with VAP due to gram-negative bacilli were randomised to a nebulized group (60 patients) and a control group (60 patients) in Shanghai Fifth People's Hospital. On the basis of similar routine treatment and systemic antibiotics based on the physicians' decision according to guidelines,the patients received 400 mg nebulized amikacin diluted in 5 mL normal saline in the nebulized group or 5 mL normal saline in the control group twice daily for 7 days. The rate of clinical cure and bacterial eradication,mortality,weaning rate and adverse events were recorded. ResultsAt the end of nebulized treatment,the rate of clinical cure in the nebulized group was significantly higher than that in the control group (75.0% vs. 53.3%,P=0.013). So was the rate of bacterial eradication (75.0% vs. 44.4%,P=0.008). But the crude mortality and weaning rate were similar between two groups (P>0.05). The adverse events in two groups were similar too (P>0.05). When followed-up to the 28th day,the weaning rate in the nebulized group was significantly higher than that in the control group (71.7% vs. 51.7%,P=0.024),but the crude mortality was not different (P>0.05). ConclusionNebulized amikacin as an adjunctive therapy for the treatment of VAP,which do not demonstrate obviously adverse events,can help improve rate of clinical cure and bacterial eradication and long-term weaning rate,but can not reduce patients' crude mortality.