ICU鲍氏不动杆菌传播途径调查分析

Routes of transmission of Acinetobacter baumannii in ICU

目的探讨鲍氏不动杆菌在ICU传播途径,为ICU耐药菌的预防控制措施提供有力证据。方法对ICU15例气管切开或插管行机械通气患者用Andersen 6级空气微生物采样器在吸痰时进行床旁(距吸痰30～50cm)空气采样,采样时间为每点10min,空气流量为(28.3L/min),37℃培养48h,并同时对每例患者吸痰后的颈前、上胸前部皮肤进行采样,在病房的中间不同区域3个点距患者的床单位约3m随机进行空气采样。结果 6级采样器采样10min所得的每层级别所测定的空气细菌平均数为14～88CFU/(皿·10min),有5例患者气道中的痰微生物培养为鲍氏不动杆菌,有3例患者在吸痰时其气溶胶中采到鲍氏不动杆菌,3～4CFU/6皿,有2例患者耐药谱与气道中痰培养的鲍氏不动杆菌完全相同,有1例患者耐药谱与气道中痰培养的鲍氏不动杆菌不同;5例患者颈胸部皮肤同时采到与气道中耐药谱相同的鲍氏不动杆菌,在病房的中间不同区域空气采样中未采到鲍氏不动杆菌。结论气溶胶的传播是开放气道吸痰时鲍氏不动杆菌不可忽视的传播途径,是ICU鲍氏不动杆菌环境污染的重要来源,应积极采取有效措施。

OBJECTIVE To investigate the routes of transmission of Acinetobacter baumanii in ICU so as to provide reliable guidance for the prevention and control of drug resistant A. baumaniii in ICU. METHODS The air samples were collected at bedside （away from the suction point 30-50 cm） from 15 patients who underwent tracheotomy or mechanical ventilation by using Andersen 6-level microbial air sampler while performing sputum suctioning. The sampling interval was 10min and the air flow rate was 28.3 L/min. The samples were then cultured at 37 ~C for 48 h. The microbiological samples were also gained from swabbing the surface area around patientrs neck and chest after sputum suctioning. Within the unit, three points with 3 meters off patients~ bed were randomly selected for air sampling. RESULTS On average, 14-88 CFU/（plate ~ 10 rain） were gained at each level using the Andersen 6-level microbial air sampler, there were 5 patients with sputum cultured positive for A. baumannii and 3 patients with A. baumannii identified among the aerosol while performing the sputum suctioning, with the bacterial colony counts of 3-4CFU/6-plates~ there were 2 patients with the exactly same drug resistance spectrum as the A. baurnannii cultured from the airway sputum and 1 patient with the drug resistance spectrum different from the A. baurnannii cultured from the airway sputum~ there were 5 patients with the same drug resistance spectrum of A. baumannii cultured from the skin swabbing samples as that from the airway sputum~ A. baurnan- nil was not found at the three randomly selected points with 3m off the patient＇s bed within the unit. CONCLUSION The aerosol is a significant way that the bacteria transmit when open-airway-suction takes place and is an important source for the environmental contamination of ICU.