Appendix

Symbols	Definition	Units
[CO2]a	Arterial CO2 content	%
[CO2]v	Venous partial CO2 content	%
ABP	Arterial blood pressure	mmHg
FRC	Functional residual capacity	ml
HR	Heart rate	beats min−1
PETCO2	End-tidal partial CO2 pressure	mmHg
M-PETCO2	Model output end-tidal partial CO2 pressure	mmHg
PkCO2	Lung compartment k partial CO2 pressure	mmHg
PtcCO2	PCO2 of blood draining the lungs	mmHg
Q	Cardiac output	l min−1
RQ	Respiratory quotient	unitless
R-R	Respiratory rate	min−1
SV	Stroke volume per breath	ml
TRESP	Respiratory interval	s
Va	Arterial blood volume	ml
Vcap	Lung capillary blood volume	ml
VD	Anatomical dead space	ml
VE	Ventilation	l min−1
V̇o2	Pulmonary O2 uptake	ml min−1
V/Q	Ventilation/perfusion ratio	unitless
VT	Tidal volume	ml
Vv	Venous blood volume	ml