title: Electronic nose analysis of bronchoalveolar lavage fluid.
abstract: BACKGROUND
  Electronic nose (E-nose) technology has been successfully used to diagnose a number of microbial infections. We have investigated the potential use of an E-nose for the diagnosis of ventilator-associated pneumonia (VAP) by detecting micro-organisms in bronchoalveolar lavage (BAL) fluid in a prospective comparative study of E-nose analysis and microbiology.
  
  
  METHODS
  BAL samples were collected using a blind technique from 44 patients following a minimum of 72 h mechanical ventilation. Control samples were collected from six patients mechanically ventilated on the intensive care unit (ICU) immediately following elective surgery. Quantitative microbiological culture and E-nose headspace analysis of the BAL samples were undertaken. Multivariate analysis was applied to correlate E-nose response with microbiological growth.
  
  
  RESULTS
  E-nose fingerprints correctly classified 77% of the BAL samples, with and without microbiological growth from patients not on antibiotics. Inclusion of patients on antibiotics resulted in 68% correct classification. Seventy per cent of isolates, cultured in the laboratory from the clinical samples, were accurately discriminated into four clinically significant groups.
  
  
  CONCLUSIONS
  E-nose technology can accurately discriminate between different microbial species in BAL samples from ventilated patients on ICU at risk of developing VAP with accuracy comparable with accepted microbiological techniques.
authors.affiliation: Biophotonics Research Unit, Gloucestershire Royal Hospital, Gloucester, UK.
authors.forename: Lee
authors.initials: L
authors.lastname: Humphreys
authors.forename: Robert M L'E
authors.initials: RM
authors.lastname: Orme
authors.forename: Philippa
authors.initials: P
authors.lastname: Moore
authors.forename: Napoleon
authors.initials: N
authors.lastname: Charaklias
authors.forename: Natasha
authors.initials: N
authors.lastname: Sahgal
authors.forename: Neus Planas
authors.initials: NP
authors.lastname: Pont
authors.forename: Naresh
authors.initials: N
authors.lastname: Magan
authors.forename: Nicholas
authors.initials: N
authors.lastname: Stone
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Kendall
mesh_terms: D018893:Bronchoalveolar Lavage / Q000379:methods*; D001992:Bronchoalveolar Lavage Fluid / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D053717:Pneumonia, Ventilator-Associated / Q000175:diagnosis / Q000382:microbiology*; D011446:Prospective Studies; D012680:Sensitivity and Specificity