An evaluation of ventilator-associated pneumonia process measure sampling strategies in a surgical ICU

Ventilator-associated pneumonia (VAP) is common, lethal, and expensive. Little is known about optimal strategies to evaluate process measures for VAP prevention. The authors conducted a prospective study of different sampling strategies for evaluating head of bed (HOB) elevation and oral care. There was no significant difference between morning and evening shift HOB elevation compliance rates (P = .47). If oral care was performed at least once during a 12-hour shift, there was an 87% probability that it also was performed at least twice. If oral care was performed at least twice during a 12-hour shift, then there was a 93% probability that chlorhexidine oral care was performed at least once. The results of this study suggest that sampling HOB elevation twice as compared with once daily is unlikely to change the estimate of performance, oral care need not be frequently sampled, and high oral care compliance may predict chlorhexidine oral care compliance.

Multi-center evaluation of the VITEK® MS system for mass spectrometric identification of non-Enterobacteriaceae Gram-negative bacilli

Studies have demonstrated that matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid, accurate method for the identification of clinically relevant bacteria. The purpose of this study was to evaluate the performance of the VITEK MS v2.0 system (bioMérieux) for the identification of the non-Enterobacteriaceae Gram-negative bacilli (NEGNB). This multi-center study tested 558 unique NEGNB clinical isolates, representing 18 genera and 33 species. Results obtained with the VITEK MS v2.0 were compared with reference 16S rRNA gene sequencing and when indicated recA sequencing and phenotypic analysis. VITEK MS v2.0 provided an identification for 92.5 % of the NEGNB isolates (516 out of 558). VITEK MS v2.0 correctly identified 90.9 % of NEGNB (507 out of 558), 77.8 % to species level and 13.1 % to genus level with multiple species. There were four isolates (0.7 %) incorrectly identified to genus level and five isolates (0.9 %), with one incorrect identification to species level. The remaining 42 isolates (7.5 %) were either reported as no identification (5.0 %) or called "mixed genera" (2.5 %) since two or more different genera were identified as possible identifications for the test organism. These findings demonstrate that the VITEK MS v2.0 system provides accurate results for the identification of a challenging and diverse group of Gram-negative bacteria.

Risk factors of ventilator-associated pneumonia in pediatric intensive care unit: a systematic review and meta-analysis

OBJECTIVE

To identify risk factors of ventilator-associated pneumonia (VAP) in pediatric intensive care unit (PICU).

METHODS

PubMed, Ovid, Web of Science, the Cochrane Library and references of retrieved articles were searched without language limitation. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by using both the Mantel-Haenszel fixed-effect and the DerSimonian-Laird random-effects models.

RESULTS

Out of the 205 initially retrieved articles, 9 papers were included. All 4,564 patients were enrolled, including 213 patients with VAP and 4,351 patients without VAP. Among fourteen risk factors, six factors had statistical significances. Risk factors of VAP and its value of OR were as follows: genetic syndrome (OR =2.04; 95% CI: 1.08-3.86), steroids (OR =1.87; 95% CI: 1.07-3.27), reintubation or self-extubation (OR =3.16; 95% CI: 2.10-4.74), bloodstream infection (OR =4.42; 95% CI: 2.12-9.22), prior antibiotic therapy (OR =2.89; 95% CI: 1.41-5.94), bronchoscopy (OR =4.48; 95% CI: 2.31-8.71).

CONCLUSIONS

Special methods of preventions should be taken in the light of risk factors of VAP in PICU so as to decrease the rate.

Bacterial superinfection following lung inflammatory disorders

The lung environment is designed to prevent innate responses to harmless commensal microorganisms and environmental antigens. Features of an intact respiratory epithelium are critical to this process. A damaged or altered lung epithelial surface will therefore remove or alter the suppressive signals delivered to local innate immune cells, and inflammation ensues. Timely resolution of inflammation is important to prevent bystander tissue damage. However, if resolving pathways themselves are prolonged or repeated, they too can cause undesirable consequences, including bacterial superinfections, which we discuss here.

Antibiotic susceptibility and genotype patterns of Pseudomonas aeruginosa from mechanical ventilation-associated pneumonia in intensive care units

Pseudomonas aeruginosa (P. aeruginosa) is a leading cause of morbidity and mortality in patients with ventilation-associated pneumonia (VAP). It is difficult to treat this infection due to acquired resistance to various antibiotics. In order to understand the potential route of transmission, it is important to have detailed knowledge of the genotypes and antibiotic susceptibility of P. aeruginosa. The aim of this study was to determine antibiotic susceptibility using the broth microdilution minimum inhibitory concentration (MIC) method and to apply the Randomly Amplified Polymorphic DNA (RAPD) typing method for VAP caused by P. aeruginosa in 16 patients (8 men and 8 women; average age at inclusion, 67.8 years; range, 53-76 years). To determine antibiotic susceptibility, imipenem (IPM), cefepime (FEP) and meropenem (MEM) were administered for the treatment of P. aeruginosa, yielding an effectiveness of 75, 62.5, and 62.5%, respectively. According to the National Committee for Clinical Laboratory Standards (NCCLS) breakpoints, 8 (50%) of the 16 mechanical ventilation (MV) isolates were resistant to ceftazidime (CAZ) and pipenacillin (PIP). Amikacin (AK) and aztreonam (AZT) were not as effective against P. aeruginosa (75%). In addition, P. aeruginosa was completely resistant to ciprofloxacin (CIP). The MV isolates were susceptible to polymyxin B (PB). RAPD analysis revealed 12 genotypes for all the isolated P. aeruginosa, separated into 4 patterns. The results demonstrated a high incidence of P. aeruginosa isolated from VAP, with endogenous and cross infections being potential reasons for P. aeruginosa isolated from VAP in the intensive care units.

Lipid peroxidation in multidrug-resistant Gram-negative sepsis: translating science to the septic patient?

Multidrug-resistant Gram-negative induced sepsis poses an increasing threat to the vulnerable intensive care patient. The study by Toufekoula and colleagues reports the serum and tissue concentration of malondialdehyde (MDA), the toxic end product of lipid peroxidation, during the course of experimental and human Gram-negative sepsis. The complementary results from this dual experimental and clinical approach argue for highly compartmentalized lipid peroxidation during sepsis. Establishing a correlation between MDA concentration and survival provides valuable insights into the pathophysiology of Gram-negative sepsis. Yet, further studies are needed to understand and establish MDA as a biomarker during sepsis aggravated by organ failure.