Table 3.

Significant values obtained via cardiopulmonary exercise testing

CPET Parameter	Value
$\dot{\text{V}}$o2 peak, ml/kg/min	20.1
$\dot{\text{V}}$o2 peak, percentage predicted	72
Peak heart rate, percentage predicted beats/min	80
Peak minute ventilation, L/min	96
Indirect maximum voluntary ventilation, L/min	137
Breathing reserve, percentage predicted	30
Oxygen saturation nadir	90
Ve:$\dot{\text{V}}$co2 nadir	47
Vd:Vt at rest	0.55
Vd:Vt at peak exercise	0.56
O2 pulse peak, percent predicted	94

Definition of abbreviations: CPET = cardiopulmonary exercise testing; Vd = dead space volume; Ve:$\dot{\text{V}}$co₂ = ventilatory equivalents for carbon dioxide; $\dot{\text{V}}$o₂ = oxygen consumption; Vt = tidal volume.

Percentage predicted breathing reserve was calculated as [1 − (peak minute ventilation/indirect maximum voluntary ventilation) × 100]; indirect maximum voluntary ventilation was calculated as forced expiratory volume in 1 second × 38. $\dot{\text{V}}$o₂ peak was mildly reduced, O₂ pulse was normal, and breathing reserve was borderline. Importantly, Vd:Vt was significantly elevated. In all, these findings are consistent with hepatopulmonary syndrome and intrapulmonary vascular dilatation physiology.