Free
Correspondence  |   July 2000
Revisiting the ASA Guidelines for Management of a Difficult Airway
Author Notes
  • Professor of Anesthesia
  • University of California, San Diego, Medical Center
  • Department of Anesthesiology
  • San Diego, California
Article Information
Correspondence
Correspondence   |   July 2000
Revisiting the ASA Guidelines for Management of a Difficult Airway
Anesthesiology 7 2000, Vol.93, 297. doi:
Anesthesiology 7 2000, Vol.93, 297. doi:
In Reply:—
The suggestion by Candido et al.  1 to change the words in the title of my editorial from “Potential Great Danger” to “Prohibitive Danger” is the result of a poor risk–benefit analysis. No one disputes the great benefit and small risk of having a stylet already in situ  in the trachea should the planned or unplanned need for reintubation arise (“simple concept”). What is disputed is the risk–benefit of using the stylet for jet ventilation. The benefit of having a safe ventilatory and oxygenating mechanism already in situ  in the trachea in case reintubation is unsuccessful is also obvious (“simple concept”). My editorial simply pointed out the many ways in which the risk of jet ventilation can be  greatly increased and, conversely, the many ways in which the risk of jet ventilation can be  greatly decreased. Therefore, if one jets with a 25-psi and 0.5-s inspiratory time through a relatively small airway exchange catheter (AEC) inserted no more than 26 cm in an adult, the ventilation risk is small. Figure 1 and the legend of figure 1 of the letter to the editor by Candido et al.  , which shows some displacement of subcutaneous tissue caused by a sustained (?) 25-psi jet from a large AEC, is misleading because the arm is richly endowed with adipose tissue and the flows over a very short period of time from this system are well-known. 2 The tidal volume from a 25-psi, 0.5-s jet from a large AEC into a lung with static compliance of 50 ml/cm H2O is approximately 350–400 ml. 2 The title of my editorial does not need to be changed; what needs to be changed is the mindset and knowledge of practitioners who use AECs about how to achieve the optimally low risk–benefit ratio of AECs.
References
Benumof JL: Airway exchange catheters: Simple concept, potentially great danger. A nesthesiology 1999; 91:342–4Benumof, JL
Gaughan SD, Benumof JL, Ozaki G: Quantification of the jet function of a jet stylet. Anesth Analg 1992; 74:580–5Gaughan, SD Benumof, JL Ozaki, G