Journal of Applied Physiology, Vol 61, Issue 6 2230-2237, Copyright © 1986 by American Physiological Society
Ventilatory response during CO2 inhalation after airway anesthesia with lidocaine
T. Y. Sullivan, E. L. DeWeese, P. L. Yu and G. R. Aronoff
Airway anesthesia with inhaled aerosolized lidocaine has been associated
with increases in minute ventilation (VE) and mean inspiratory flow rate
(VT/TI) during CO2 inhalation. However, it is unclear whether these
increases are local effects of the anesthesia or systemic effects of
absorbed and circulating lidocaine. To evaluate this 20 normal subjects
were treated on separate days with aerosolized lidocaine, intravenous
lidocaine, aerosolized control solution, or intravenous control solution,
and the effects of each treatment on VE and VT/TI were determined and
compared during room-air breathing and inhalation of 5% CO2-95% O2. None of
the treatments altered VE or VT/TI during room-air breathing. Aerosolized
lidocaine produced small (5.9-6.0%) increases in VE and VT/TI during CO2
inhalation, but these effects were not present after intravenous lidocaine
despite equivalent lidocaine blood levels. We concluded that the increases
in VE and VT/TI after aerosolized lidocaine were local effects of airway
anesthesia rather than systemic effects of absorbed and circulating
lidocaine.
