Rationale: Diagnosis of ventilator-associated pneumonia (VAP) is imprecise.Objectives: To (1) determine whether alternate-day surveillance mini-bronchoalveolar lavage (mini-BAL) in ventilated adults could reduce time to initiation of targeted treatment and (2) evaluate the potential for automated microscopy to reduce analysis time.Methods: Adult intensive care unit patients who were anticipated to require ventilation for at least a further 48 hours were included. Mini-BALs were processed for identification, quantitation, and antibiotic susceptibility, using (1) clinical culture (50 6 7 h) and (2) automated microscopy (z5 h plus offline analysis).Measurements and Main Results: Seventy-seven mini-BALs were performed in 33 patients. One patient (3%) was clinically diagnosed with VAP. Of 73 paired samples, culture identified 7 containing pneumonia panel bacteria (.10 4 colony-forming units/ml) from five patients (15%) (4 Staphylococcus aureus [3 methicillin-resistant S. aureus], 2 Stenotrophomonas maltophilia, 1 Klebsiella pneumoniae) and resulted in antimicrobial changes/additions to two of five (40%) of those patients. Microscopy identified 7 of 7 microbiologically positive organisms and 64 of 66 negative samples compared with culture. Antimicrobial responses were concordant in four of five comparisons. Antimicrobial changes/additions would have occurred in three of seven microscopy-positive patients (43%) had those results been clinically available in 5 hours, including one patient diagnosed later with VAP despite negative mini-BAL cultures.Conclusions: Microbiological surveillance detected infection in patients at risk for VAP independent of clinical signs, resulting in changes to antimicrobial therapy. Automated microscopy was 100% sensitive and 97% specific for high-risk pneumonia organisms compared with clinical culturing. Rapid microscopy-based surveillance may be informative for treatment and antimicrobial stewardship in patients at risk for VAP.

Basic neurophysiological principles necessary for understanding the effectiveness of transcutaneous electrical nerve stimulation are presented. Peripheral and central neural mechanisms are reviewed, and the effects of individual pulse characteristics on neural excitability are analyzed. Representative commercial stimulators are compared, and wave-forms for different load conditions are illustrated. Discussion includes important considerations for clinical effectiveness and for patient acceptance and safety.

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Background Methods Results Conclusions Introduction. Clinical diagnosis of VAP is imprecise. Cumbersome microbiological identification and antimicrobial sensitivity testing techniques delay treatment and are associated with increased morbidity, mortality and antimicrobial resistance. W e hypothesized that rapid microbiological detection and sensitivity reporting from mini-BAL samples obtained during surveillance of at-risk mechanically ventilated (MV) adults would reduce time to initiation of targeted treatment for VAP compared with a clinical and quantitative-culture guided approach. Methods. Adult MICU patients with identified surrogate were included within 72 hours of intubation and if anticipated to require MV for >48h. Moribund state or pregnancy were exclusions. Surveillance mini-BAL (Combicath, Plastimed) was performed on Day 1, 3, 5, 7 and 10 of MV. Samples were processed for both a) routine respiratory quantitative microbiological culture (QCx) and sensitivity assays (> 48h result availability) and b) rapid (<8 hour) flowcell/surface-capture and automated microscopy (MADM). Viable bacteria were identified using growth analysis enhanced by a focused VAP antibody panel (S. aureus, P. aeruginosa, A. baumannii). Untypable organisms were also reported. Sensitivity was assessed using growth analysis. Attending physicians were blinded to MADM results. Results. 77 miniBALs (median 2; Range 1-7 per patient) were performed on 33 MV patients (Median age 55, range 26-84 years; 30% Female; 52% active smokers, Median APACHE II 21 (IQR 16-24). 20 (61%) patients had diffuse or patchy CXR infiltrates and 3 patients had no infiltrates on enrollment. 70 BAL samples were tested using MADM. 12 samples grew ≥ 1 bacterial type at >104 CFU/mL by QCx. 8 samples contained mixed respiratory bacteria. 7 samples contained VAP associated bacteria (4 S. aureus (incl 1 auxotroph and 3 MRSA), 2 S. maltophilia, 1 K. pneumoniae). MADM identified 3 of 4 target organisms accurately and antimicrobial response enabled identification of 2 of 2 S. maltophilia. A K. pneumoniae sample was reported untypable. Auxtrophic growth precluded testing for 1 S. aureus sample. Antimicrobial response matched in 5 samples (3 MRSA, 2 S. maltophilia). 14 samples grew ≥ 1 bacterial type at < 104 CFU/mL by QCx. 10 samples contained mixed respiratory bacteria, 3 samples yeast, 2 samples lactose fermenting GNB, 1 sample non lactose fermenting GNB, 1 sample H. influenzae, beta lactamase positive, 1 sample H. species, not influenzae, 1 sample Beta hemolytic Streptococcus. None of the patients having bacteria detected by QCx at <104 CFU/mL developed clinical VAP. In 98% of samples MADM was concordant with QCx-negative samples. MADM detected a enteric organism (10 5)) in one sample negative by QCx. One VAP was diagnosed by clinical criteria. MADM based ID would have resulted in important and earlier antibiotic change/addition in 63% of mini-BAL samples with above threshold target organisms by QCx. Conclusions. MADM is 100% specific and had 85% identification consisten...

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