Ventilation during bronchoscopy

An evaluation of the jet injector (sanders) technique for bronchoscopy in paediatric patients

“…Another concern has been the possible occurrence of excessive pressures, especially in children where bronchoscopes tend to fit snugly, if the proximal end is accidentally obstructed. 4 In such a circumstance it should be theoretically possible to produce intrathoracic pressures equal to the driving pressure (138-345 kPa or 20-50 psi). However, this was not the case with the Sanders adapter because of multiple vent holes in the side and its rough surface.…”

“…Relationship of maximal inflation pressure to the angle at which the jet is inserted into tapered bronchoscopes (3,4,5,and 6 mm ID). cannula, the inflation pressure increased 24 per cent at a depth of 8 cm but then decreased drastically to -40 per cent with further insertion of the cannula.…”

“…4 Jardine, Harrison and Healy have also explored in a lung model the influence of changes in "patient" airway resistance and lung compliance on entrainment ratios and the resulting delivered oxygen concentrations and tidal volume, s These investigations have clarified many of the inter-relationships affecting the operation of jet injector systems and provided the knowledge required for their safe effective use. However, reports of the application of the jet injector technique in a paediatric population are fragmentary.…”

Technique of ventilation during endolaryngeal surgery under general anaesthesia

“…The transtracheal approach is preferred over the puncture of the cricothyroid membrane; it brings the jet further away from the larynx, avoiding the chance that it may accidentally be grasped by a biopsy forceps and it makes it possible to enter the trachea more tangentially, thus avoiding kinking of the needle between tissue planes, Occasionally it may be desirable to puncture the trachea some distance below the cricoid in order to bypass a subglottic lesion. 4 The use of a curved plastic cannula, as proposed by Jacobs" would appear to have some advantages over a straight needle, but such a cannula is presently not available.…”

Technical report evaluation of the jet injector in paediatric fibreoptic bronchoscopes

“…The Sanders venturi system has been used in such cases in both adults and children. [2][3][4] When jet ventilation is used in bronchoscopy, peak inflation pressures and peak flow rates are influenced by the driving pressure, the inside diameter of the injector, the diameter of the bronchoscope, and the leak around the bronchoscope. 2'5'6 In a study of the Sanders injector with paediatric bronchoscopes we demonstrated that the distance of the injector from the proximal end of the bronchoscope and the angle of the jet from the axial line are also important in small-diameter bronchoscopes.…”