title: Temporal course of gas exchange and mechanical compensation after right pneumonectomy in immature dogs.
abstract: To determine the temporal progression and magnitude of functional compensation in immature dogs raised to maturity after extensive lung resection, we performed right pneumonectomy (R-Pnx) or right thoracotomy without pneumonectomy (Sham) in matched foxhounds at 2 mo of age. At 4, 8, 20, 40, and 60 wk after surgery, static transpulmonary pressure-lung volume relationships were determined. Lung diffusing capacity, membrane diffusing capacity, pulmonary capillary blood volume, pulmonary blood flow, septal lung tissue volume, and lung volumes were measured simultaneously by a rebreathing technique. During maturation, total lung capacity, lung volume at a given distending pressure, and compliance were lower in the R-Pnx group than in the Sham group (P < 0.05). Pulmonary viscous resistance at maturity was elevated after R-Pnx. There were no significant differences in total lung diffusing capacity, membrane diffusing capacity, pulmonary capillary blood volume, pulmonary blood flow, and septal lung tissue volume between groups. Compensation of alveolar-capillary gas exchange was complete by 4-8 wk after R-Pnx, but compensation of mechanical properties remained incomplete throughout maturation. Relative magnitude of compensation after R-Pnx was greater in immature dogs than in adult dogs studied previously by similar techniques.
authors.affiliation: Department of Medicine and Surgery, University of Texas Southwestern Medical Center, Dallas 75235-9034, USA.
authors.forename: S
authors.initials: S
authors.lastname: Takeda
authors.forename: E Y
authors.initials: EY
authors.lastname: Wu
authors.forename: M
authors.initials: M
authors.lastname: Ramanathan
authors.forename: A S
authors.initials: AS
authors.lastname: Estrera
authors.forename: C C
authors.initials: CC
authors.lastname: Hsia
mesh_terms: D000403:Airway Resistance / Q000502:physiology; D000818:Animals; D004285:Dogs; D008168:Lung / Q000502:physiology* / Q000601:surgery; D008297:Male; D011013:Pneumonectomy; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D013997:Time Factors