Objective: To analyze the bacterial colonization results in mechanical ventilation pipeline in pediatric intensive care unit (PICU)

and to further explore the preventive measures of ventilator-associated pneumonia (VAP) in children. Methods: Totally 164 children with mechanical ventilation in PICU from Jan. to Oct. 2018 were extracted. The samples of different parts of lower respiratory tract and ventilator pipeline (including inlet and outlet of threaded tube

condensate at inlet and outlet of inlet and outlet air

Y-junction and humidification tank mouth) were collected for bacterial culture. The incidence of VAP in children

results of bacterial culture and bacterial distribution in lower respiratory tract and ventilator pipeline were observed. Results: The incidence of VAP in PICU was 17.07%(28/164). The longer the mechanical ventilation

the higher the incidence of VAP in children (P<0.05). The positive rate of bacteria culture in the lower respiratory tract of children with mechanical ventilation at 0~3 d

4~7 d and >7 d increased successively (P<0.05). The positive rate of bacterial culture at the inlet and outlet of the threaded tube and at the mouth of the wetting tank was significantly lower than that at the condensate water and Y-junction of the inlet and outlet (P<0.05). Totally 142 strains (49.13%) of bacteria were cultured in the lower respiratory tract

147 strains (50.87%) were cultured in the ventilator pipeline

and the coincidence rate was 96.60% (142/147). Gram-negative bacteria accounted for the highest proportion of bacteria cultured in the lower respiratory tract and ventilator pipeline

accounting for 55.71%

of which 76 strains (26.30%) were cultured in the lower respiratory tract

and 85 strains (29.41%) were cultured in the ventilator pipeline

with the coincidence rate of 89.41%. The results of lower respiratory tract bacterial colonization were positively correlated with the results of ventilator tube colonization (r=0.914

P<0.05). Conclusion: The bacteria cultured in lower respiratory tract and ventilator pipeline are basically the same

suggesting that the occurrence of VAP in children in PICU is closely related to the bacterial colonization in ventilator pipeline. Clinically

children should be separated from the ventilator as soon as possible

and attention should be paid to the disinfection of mechanical ventilation pipeline

so as to effectively prevent the occurrence of VAP in children in PICU.