Intubation-related Reflex Atelectasis of Lung Lobes During Computed Tomography in Two Dogs

In dogs, transient perioperative atelectasis is predominantly attributed to passive mechanisms, including compressive and resorptive atelectasis ( De Monte et al., 2013 De Monte V. Grasso S. De Marzo C. et al. Effects of reduction of inspired oxygen fraction or application of positive end-expiratory pressure after an alveolar recruitment maneuver on respiratory mechanics, gas exchange, and lung aeration in dogs during anesthesia and neuromuscular blockade. Am J Vet Res. 2013; 74: 25-33 Crossref PubMed Google Scholar ). This typically manifests as small areas of atelectasis ( De Monte et al., 2013 De Monte V. Grasso S. De Marzo C. et al. Effects of reduction of inspired oxygen fraction or application of positive end-expiratory pressure after an alveolar recruitment maneuver on respiratory mechanics, gas exchange, and lung aeration in dogs during anesthesia and neuromuscular blockade. Am J Vet Res. 2013; 74: 25-33 Crossref PubMed Google Scholar ). By contrast, large areas of atelectasis (e.g., lobar) during anesthesia are rare, with some cases in humans attributed to reflex bronchoconstriction induced by vagal nerve stimulation following mechanical stimulation of the laryngeal mucosa ( De Takats et al., 1942 De Takats G. Fenn G.K. Jenkinson E.L. Reflex pulmonary atelectasis. J Am Med Assoc. 1942; 120: 686-690 Crossref Google Scholar ; Yoo et al., 2009 Yoo K.Y. Kim S.J. Jeong C.W. et al. Recurrent attacks of post-intubation right upper lobe atelectasis. Acta Anaesthesiol Taiwan. 2009; 47: 212-215 Crossref PubMed Scopus (0) Google Scholar ; Uzman et al., 2012 Uzman S. Toptaş M. Yanaral T.U. Right upper lobe atelectasis after tracheal extubation in a morbidly obese patient. Am J Case Rep. 2012; 13: 146-168 Crossref PubMed Scopus (1) Google Scholar ). This letter describes suspected intubation-related reflex atelectasis causing unilateral lung atelectasis in two dogs.