Influence of subglottic secretion drainage on the microorganisms of ventilator associated pneumonia: A meta-analysis for subglottic secretion drainage.

Background: The influence of the subglottic secretion drainage (SSD) on the microorganisms of ventilator associated pneumonia (VAP) is still unclear. A meta-analysis focusing on the influence of the SSD on the microorganisms of VAP. Methods: A comprehensive search was conducted through the online studies of PubMed, Embase, Cochrane Library, Google scholar, CNKI (China National Knowledge Infrastructure), and VIPI (Database for Chinese Technical Periodicals) using specific search terms. Included studies were randomized controlled trials (RCTs) that compare the microorganisms of VAP between SSD and standard endotracheal tube care in mechanically ventilated adults. Results: Nine RCTs were eligible. There was no significant difference in the rate of VAP caused by nonfermentative bacteria and enterobacteria between SSD group and control group (OR=0.73, 95% CI, 0.53-1.01; P=.06). The episodes of VAP caused by Gram-positive cocci and Haemophilus influenzae organisms were lower in the SSD group (OR=0.29, 95% CI, 0.18-0.48; P<0.00001). Less mean volume of SSD daily was observed in VAP group (OR=-16.97, 95% CI, -29.87-4.08; P=.010). Conclusion: We found SSD to be associated with significant decreases in VAP caused by Gram-positive cocci and H influenzae organisms but no significant differences in VAP caused by nonfermentative bacteria and enterobacteria. Less mean volume of SSD daily was observed in VAP group.