Differential changes of alveolar gas concentrations during anesthetic induction of a patient with an absent right pulmonary artery.

Abstract

A 38-yr-old man with congenital right pulmonary artery agenesis, whose right lung was perfused with collateral systemic arterial blood, presented for right pneumonectomy. Because of a likely difference in gas exchange between the two lungs, we sampled end-tidal gases from each lung individually, as well as from the common gas outlet of a double-lumen endobronchial tube. Our results indicated a higher end-tidal CO2 from the left, normally perfused, lung than from the right, systemically perfused, lung. We also determined uptake of sevoflurane from each lung, demonstrating a more rapid uptake in the left lung than in the right. In conclusion, we report the rare case of unilateral pulmonary artery agenesis with systemic arterial collateralization and characterize the differences in gas exchange.