Pooling of secretions above the endotracheal tube cuff
may increase the volume of bacteria that enter the airways.
Removal of these secretions by continuous aspiration
in the subglottic region requires the use of a specialized
endotracheal tube with a second lumen that permits a
suction catheter to exit proximal to the endotracheal tube
cuff. A meta-analysis identified 13 randomized controlled
trials that met the inclusion criteria. Of the 13 trials, 12
reported reduced VAP rates in the group that had subglottic
secretion drainage. The overall RR for VAP was 0.55
(95% CI 0.46 to 0.66, P < 0.00001). The use of subglottic
secretion drainage was associated with reduced ICU LOS
(−1.52 days; 95% CI −2.94 to −0.11, P = 0.03); decreased
duration of mechanical ventilation (−1.08 days; 95% CI
−2.04 to −0.12, P = 0.03), and increased time to first episode
of VAP (2.66 days; 95% CI 1.06 to 4.26, P = 0.001).
There were no beneficial effects on adverse events or on
hospital or ICU mortality.184 In the patients anticipated
to have a prolonged course of intubation with mechanical
ventilation, the use of endotracheal tubes with subglottic
secretion drainage appears effective for the prevention of
VAP. The reduction of the number of oral microorganisms
in the secretions with oral care and 2% chlorhexidine also
appears to be beneficial for VAP prevention in a recent
meta-analysis (RR 0.72; 95% CI 0.55 to 0.94, P = 0.02).185