Table 3.

Effect of the duration of dopamine infusion on the ventilatory reaction to dopamine withdrawal

		Change after dopamine withdrawal (%)
Measured parameter	Duration of dopamine infusion (min)	Subject A	Subject B
Minute ventilation	15	+11	+10
	60	+19	+50
Tidal volume	15	+11	−1
	60	+36	+60
Breathing rate	15	+1	+19
	60	−14	−7

Note that the pronounced increase in minute ventilation observed with long administration is mainly driven by an increment in tidal volume. Subject A has hypoxic ventilatory response of 0.2 l min^–1/ and subject B of 1.1 l min^–1/.