Pulmonary Gas Exchange and Exercise Capacity in Adults Born Preterm

Rationale: Preterm birth, and its often-required medical interventions, can result in respiratory and gas exchange deficits into childhood. However, the long-term sequelae into adulthood are not well understood.Objectives: To determine exercise capacity and pulmonary gas exchange efficiency during exercise in adult survivors of preterm birth.Methods: Preterm (n = 14), very low birth weight (<1,500 g) adults (20–23 yr) and term-born, age-matched control subjects (n = 16) performed incremental exercise on a cycle ergometer to volitional exhaustion while breathing one of two oxygen concentrations: normoxia (fraction of inspired oxygen, 0.21) or hypoxia (fraction of inspired oxygen, 0.12).Measurements and Main Results: Ventilation, mixed expired gases, arterial blood gases, power output, and oxygen consumption were measured during rest and exercise. We calculated the alveolar-to-arterial oxygen difference to determine pulmonary gas exchange efficiency. Preterm subjects had lower power output at volitional exh...