Correspondence  |   October 2007
Pressure-support Ventilation in the Operating Room
Author Affiliations & Notes
  • Jan Ehrenwerth, M.D.
  • *Yale University, School of Medicine, New Haven, Connecticut.
Article Information
Correspondence   |   October 2007
Pressure-support Ventilation in the Operating Room
Anesthesiology 10 2007, Vol.107, 670-671. doi:
Anesthesiology 10 2007, Vol.107, 670-671. doi:
In Reply:—
We appreciate Dr. Feldman's comments on our editorial.1 Before extubating patients in the operating room, the anesthesiologist typically evaluates the patient's respiratory effort, tidal volume, and respiratory rate, as well as the patient's oxygen saturation and carbon dioxide elimination. To compensate for the difficulties of breathing through an endotracheal tube and the breathing circuit, we frequently apply continuous positive airway pressure using the adjustable pressure-limiting valve on the anesthesia machine. Knowing that continuous positive airway pressure is functionally a combination of pressure-support ventilation and positive end-expiratory pressure, the level of support is typically minimal. If the level of support were significant, the patient could be falsely judged as ready for extubation. At the conclusion of the procedure, the adjustable pressure-limiting valve is usually fully opened so that the patient's respiratory performance can be evaluated with zero support. If the pressure-support ventilation mode is used until the patient is extubated, we think that the anesthesiologist may get a false sense of security regarding the patient's readiness for extubation. Although this is a common practice in the intensive care unit, we are not sure whether the same practice applies to the operating room. Patients in the operating room temporarily have an acute change in their respiratory status, whereas intensive care unit patients have a more prolonged weaning period before extubation.
Although using the pressure-support ventilation mode with the ventilator in the operating room may be new for some anesthesiologists, anesthesiology residents are familiar with it from their training in the intensive care unit. We think that it is important to emphasize to our residents the need to first look at the patient and do a clinical assessment before relying on mechanical devices. Therefore, the question is still whether there is enough benefit to the patient to justify the increase in cost to add the pressure-support ventilation mode.
*Yale University, School of Medicine, New Haven, Connecticut.
Tantawy H, Ehrenwerth J: Pressure-support ventilation in the operating room: Do we need it? Anesthesiology 2006; 105:872–3Tantawy, H Ehrenwerth, J