1. Air entrainment during high-frequency jet ventilation in a model of upper tracheal stenosis† 
P.W. Buczkowski, F.N. Fombon, E.S. Lin, W.C. Russell, J.P. Thompson 
British Journal of Anaesthesia 
Volume 99, Issue 6, Pages (December 2007)
DOI: /bja/aem312
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

2. Fig 1
Lung–trachea model with dimensions. ASV, TSV, and BSV configurations aimed to simulate supraglottic, transglottic, and transtracheal ventilation, respectively, in the clinical situation. The detachable model pharynx was used in the second set of experiments (Table 1).
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

3. Fig 2
Peak distal airway pressures during ASV and BSV were very similar with and without simulated pharynx. Data shown as mean (95% CI).
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

4. Fig 3
Mean (95% CI) minute volumes during ASV, TSV, and BSV (Experiment 2 set 1;  1). Minute volumes were greater during ASV compared with between BSV and TSV at equivalent stenosis diameters. During ASV, there was a non-linear relationship between minute volume and diameter of stenosis. Minute volume was highest at around 4–5.5 mm stenosis diameters and decreased at smaller and greater diameters. In contrast, minute volume was more or less constant during BSV and TSV.
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

5. Fig 4
The presence of model pharynx produced little change in minute volume during ASV or BSV. Data shown as mean (95% CI).
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

6. Fig 5
Balance gas concentrations recorded during BSV or TSV were negligible, in contrast to high concentrations measured during ASV (Experiment 3 set 1;  1). Data shown as mean (95% CI).
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

7. Fig 6
The addition of a model pharynx (in set II) resulted in significant reduction in balance gas concentrations during ASV but had no effect on the (negligible) concentrations during BSV. Data shown as mean (95% CI).
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions

8. Fig 7
Oxygen concentrations recorded during ASV with simulated pharynx (Experiment 3 set II; Table 1). The observed increase in oxygen concentrations during ASV with simulated pharynx was associated with reduction in balance gas concentrations and preserved minute volume (Fig. 4) suggesting the entrainment of oxygen, which was used as the driving gas. Data shown as mean (95% CI).
British Journal of Anaesthesia  , DOI: ( /bja/aem312)
Copyright © 2007 British Journal of Anaesthesia Terms and Conditions