Prevention of Intensive Care Unit-acquired Pneumonia

Michael Klompas, MD, MPH


Semin Respir Crit Care Med. 2019;40(4):548-557. 

In This Article


Probiotics are hypothesized to moderate the microbiome of the aerodigestive tract, decrease colonization with pathogenic organisms, and therein protect patients from aspirating the organisms that lead to hospital-acquired pneumonia. Many studies have been conducted to test this hypothesis but most have been small, variably blinded, single-center assessments with discrepant results. A recent meta-analysis of 13 randomized trials with 1,969 adults and children did report a significant association between probiotics and lower VAP rates (RR: 0.73; 95% CI: 0.60–0.89) but no difference in duration of mechanical ventilation, ICU length of stay, or mortality.[102] Notably, the meta-analysis did report near-significant trends toward lower mortality rates (RR: 0.84; 95% CI: 0.70–1.02; p = 0.09) and shorter duration of mechanical ventilation (−3.32 days, 95% CI: −6.74 to +0.09, p = 0.06) in patients randomized to probiotics, so future studies may reveal clearer evidence of net benefit.[102] There is a large multicenter randomized trial of this intervention underway that may be helpful in this regard.[103]

Note that there is some risk associated with probiotics. There are multiple case reports of bloodstream infections with probiotic strains following exposure to these agents.[104–106] Probiotics are therefore contraindicated in patients with impaired immunity, severe pancreatitis, and short-gut syndrome. There have also been reports of airborne transmission of probiotic strains within intensive care units.[107,108]