Is reprocessing after disuse a safety procedure for bronchoscopy?: A cross-sectional study in a teaching hospital in Rome.

A bacteriological assessment of flexible bronchoscopes that were stored after a reprocessing procedure was performed to determine whether reprocessing removes microbiological contamination and whether the instruments could be used safely after extended storage without repeating the disinfection before bronchoscopy. The microbiological quality of manual and automated reprocessed bronchoscopes was examined by collecting a pre-reprocessing and a post-reprocessing liquid sample from the stored instruments' channels. A qualitative microbiological analysis was performed to evaluate bacterial contamination. Among the 264 pre-reprocessing bronchoscopes, 10 were contaminated (13 human flora strains and 1 environmental strain were detected). After reprocessing, 8 were decontaminated and 2 remained contaminated. Furthermore, 12 other bronchoscopes had a new contamination post-reprocessing (11 human flora and 3 environmental strains were detected). In addition, 2 sampled bronchoscopes were contaminated both pre- and posttreatment. Our findings support the suggestion that reprocessing after storage can be avoided in the safe usage of the instrument if earlier decontaminations are performed correctly. Having found that reprocessing could contaminate bronchoscopes, additional studies are needed to identify the risk factors for contamination and avoid controversial suggestions for first-use reprocessing.

Effects of acute hypoventilation and hyperventilation on exhaled carbon monoxide measurement in healthy volunteers.

BACKGROUND: High levels of exhaled carbon monoxide (eCO) are a marker of airway or lung inflammation. We investigated whether hypo- or hyperventilation can affect measured values. METHODS: Ten healthy volunteers were trained to achieve sustained end-tidal CO2 (etCO(2)) concentrations of 30 (hyperventilation), 40 (normoventilation), and 50 mmHg (hypoventilation). As soon as target etCO(2) values were achieved for 120 sec, exhaled breath was analyzed for eCO with a photoacoustic spectrometer. At etCO(2) values of 30 and 40 mmHg exhaled breath was sampled both after a deep inspiration and after a normal one. All measurements were performed in two different environmental conditions: A) ambient CO concentration = 0.8 ppm and B) ambient CO concentration = 1.7 ppm. RESULTS: During normoventilation, eCO mean (standard deviation) was 11.5 (0.8) ppm; it decreased to 10.3 (0.8) ppm during hyperventilation (p < 0.01) and increased to 11.9 (0.8) ppm during hypoventilation (p < 0.01). eCO changes were less pronounced than the correspondent etCO(2) changes (hyperventilation: 10% Vs 25% decrease; hypoventilation 3% Vs 25% increase). Taking a deep inspiration before breath sampling was associated with lower eCO values (p < 0.01), while environmental CO levels did not affect eCO measurement. CONCLUSIONS: eCO measurements should not be performed during marked acute hyperventilation, like that induced in this study, but the influence of less pronounced hyperventilation or of hypoventilation is probably negligible in clinical practice.