This impressive result for an inexpensive, nontoxic, topically applied modality warrants further attention but is difficult to reconcile with the absence of effect on ventilator-days, length of stay, or mortality. It is important to measure how prophylactic use of chlorhexidine and chlorhexidine-colistin complement other effective prevention strategies, and resistance could become an important issue over time. so
Iseganan, a topical antimicrobial peptide, active against aerobic and anaerobic Gram-positive and Gram-negative bacteria and yeasts, was evaluated in a randomized, double-bind trial to prevent VAP. Although there was a significant reduction in colonization in the treatment group, the rate of VAP among survivors (16% vs 20%) and 14-day morality was similar (22% vs 18%). Although protegrins are ubiquitous antimicrobial peptides, and in human trials were able to reduce oral colonization by two logs, these results raise several questions about ise-ganan efficacy and why it failed.
Interesting data from a double-blind pilot study of subjects randomized to oral and gastric lactobacillus GG (2 X 109 colony forming units bid) [n = 19] vs placebo (n = 21) were presented by Morrow and coworkers at the 2005 American Thoracic Society Annual Meeting Symposium in San Diego. Demographics and acute physiology and chronic health evaluation (APACHE) II scores were similar in the two groups, but the lactobacillus GG group had significantly higher rates of colonization with normal flora (p < 0.03), fewer oral pathogens, less clinical VAP (26% vs 45%. p = 0.2), lower microscopic VAP (11% vs 33%, p = 0.08), and a lower mortality rate (0% vs 10%, p = 0.17). Further studies are in progress.
Noninvasive positive pressure ventilation (NPPV) provides ventilatory support without the need for intubation and for earlier removal of the endotracheal tube to reduce complications related to prolonged intubation. Burns and coworkers, in a recent Cochrane review, reported significant benefits: decreased mortality (risk ratio [RR], 0.41; 95% confidence interval [CI], 0.22 to 0.76), lower rates of VAP (RR 0.28; 95% CI, 0.0.90 to 0.85); decreased length of ICU and shorter hospital stays; and lower duration of mechanical support. The impact of NPPV is greater in patients with COPD exacerbations or congestive heart failure than for patients with VAP. Recent data also indicate that NPPV may not be a good strategy to avoid reintubation after initial extubation, and is recommended for hospitals with staff who are experienced in this technique.