Dow A C, Goodman N W
University Department of Anaesthesia, Medical School Unit, Southmead Hospital, Bristol.
Br J Anaesth. 1993 May;70(5):532-5. doi: 10.1093/bja/70.5.532.
We have assessed the effects on the pattern of breathing of changing the inspired gas from air to oxygen, by analysing the 15 breaths before and 15 breaths after the change, in 10 patients anaesthetized with propofol. Eight of 14 changes decreased tidal volume (P < 0.01) by between 16% and 30%. Nine changes increased ventilatory cycle time (P < 0.01) by between 8% and 16%. Total ventilation decreased by between 7% and 33%. The peripheral chemoreceptors are active during propofol anaesthesia, and patients should be able to respond to hypoxia.
