每周更換呼吸器管路對呼吸器相關肺炎有幫助嗎？

Does Weekly Change of the Ventilator Circuit Really Matter in Preventing Ventilator Associated Pneumonia?

簡介：醫療照護相關肺炎是院內感染重要原因之一，而呼吸器相關肺炎佔醫療照護相關肺炎的重要角色。其中呼吸器管路的衛生非常重要。關於呼吸器管路的更換期限之前多有爭議，因此本篇研究在於探討呼吸器管路要每周定期更換還是只要培養不長菌，超過一周更換也可以。研究方法：採用回朔性病歷研究，病人來源為中部某醫學中心兒科加護病房，收案期間為2007年11月至2008年12月。病人皆小於18歲且使用呼吸器。呼吸器相關肺炎依醫院感染控制委員會標準收案。控制組為插管超過一周，直到痰培養陽性才換管路，另一組則是7天更換。結果：每周更換組佔848人日，控制組850人日。呼吸器相關肺炎於每周更換組發生率為5.9/1000人日，控制組為3.8/1000人日， R R=1.71(95％ C I 0.41-7.12，P=0.46)。結論：每周更換呼吸器管路對於預防呼吸器相關肺炎並未優於超過一周更換者。但若呼吸器管路受到污染仍應更換。我們仍須大量前瞻性研究來研討呼吸器管路應多久更換。

Introduction: Health-care associated pneumonia is the leading cause of death in patients with hospital acquired infections, and ventilator associated pneumonia (VAP) is an important part of this. The hygiene of ventilator tubing is considered to be a risk factor; however, the frequency of the need to change the ventilator circuit is controversial. The aim of this study was to determine if it was beneficial to change it weekly rather than the current policy of routine change when the sputum culture turned positive. Patients and Methods: This was a retrospective cohort study and the data were gathered from a medical center from November 2007 to December 2008. All patients under eighteen years of age who underwent ventilator support were enrolled. Demographic data were retrieved from charts and a review of nursing records. The diagnosis of ventilator associated pneumonia (VAP) was determined by the hospital infection control committee. In one group, the ventilator circuit was changed weekly and, in the reference group, it was changed when the sputum culture turned positive. Results: There were 848 person-days in the weekly change group, and 850 person-days in the reference group. The incidence of VAP was 5.9 per 1000 persondays with weekly change and 3.8 per 1000 person-days in the reference group RR=1.71(95% CI 0.41-7.12, P=0.46). Conclusion: Routine weekly change of the ventilator circuit had no significant effect on the prevention of VAP. Tubing should still be changed once it is contaminated. Further prospective and larger scale studies are needed to determine the optimal interval for changing circuits.