Clinicopathologic features, comorbid diseases, and prevalence of pulmonary hypertension in dogs with bronchomalacia

Abstract

Background Reports of clinicopathologic features of bronchomalacia (BM) differ because of inconsistent definitions and frequent prevalence of comorbid cardiopulmonary disease. Pulmonary hypertension (PH) secondary to BM is poorly described. Objectives Dogs with BM will be older but of any somatotype, and increased expiratory effort, ≥1 comorbid disease, and PH will be more common than in dogs without BM. Animals Client‐owned dogs (n = 210) evaluated for respiratory signs. Methods Medical records of dogs with paired inspiratory: expiratory‐breath‐hold computed tomography, tracheobronchoscopy, or both between January 2016 and December 2019 were retrospectively reviewed. Comparisons between dogs with and without BM using Mann‐Whitney rank sum or χ2 tests (P < .05 significant were made). Because of high numbers of variables, criteria with high prevalence (>25%) were identified (n = 10) for univariate analysis (P < .005 significant). Significant variables were submitted for multivariate analysis. Results Bronchomalacia was identified in 41% of dogs of all sizes/somatotypes; 38% were >10 kg. All dogs with BM had ≥1 comorbid cardiopulmonary disorder. Dogs with BM were significantly older (P < .001), smaller (P < .001), and were more likely diagnosed with tracheal or mainstem bronchial collapse (P < .001) or bronchiectasis (P < .001). Multivariate analysis confirmed associations with age, tracheal or mainstem bronchial collapse, and bronchiectasis. In dogs with BM, PH was more prevalent. Conclusions and Clinical Importance Although significantly more common in older, smaller dogs, BM occurs in dogs of all sizes and in all instances with comorbidities. Echocardiography should be considered in dogs with BM to identify PH.

Prospective evaluation of the efficacy of inhaled steroids administered via the AeroDawg spacing chamber in management of dogs with chronic cough

“…In our study, empiric diagnosis of AWC was based on physical examination and radiographic changes although neither of these variables has a high sensitivity, 2,3,30 and bronchoscopy is still considered the gold standard for AWC diagnosis 3 . Additionally, our cohort of dogs was generally older, smaller, and overweight, which is similar to the description of the cohort of dogs with bronchomalacia in prior studies 1,28,30,31 . We conclude that empiric fluticasone should be considered in dogs with advanced MMVD in which general anesthesia is considered risky and for which there exists a high clinical suspicion for AWC as the cause of chronic non‐cardiogenic cough, because there likely is a concurrent inflammatory component.…”

“…3 Additionally, our cohort of dogs was generally older, smaller, and overweight, which is similar to the description of the cohort of dogs with bronchomalacia in prior studies. 1,28,30,31 We conclude that empiric fluticasone should be considered in dogs with advanced MMVD in which general anesthesia is considered risky and for which there exists a high clinical suspicion for AWC as the cause of chronic non-cardiogenic cough, because there likely is a concurrent inflammatory component. Bronchoscopy is still recommended for definitive diagnosis of complicating conditions in dogs that are suitable anesthetic candidates.…”

Ventilator-Assisted Inspiratory and Expiratory Breath-Hold Thoracic Computed Tomographic Scans Can Detect Dynamic and Static Airway Collapse in Dogs with Limited Agreement with Tracheobronchoscopy

“…Bronchomalacia, defined as collapse of segmental/subsegmental airways [ 1 ], tends to be diffuse and may also have a marked impact on lung function. While tracheal and mainstem bronchial collapse is prevalent in middle-aged to old dogs weighing less than 10 kg [ 2 , 3 , 4 ], bronchomalacia, which is defined herein, affects dogs of all ages and weights [ 3 ]. In contrast, lobar bronchial collapse is frequently anatomically limited (e.g., only affecting one or few lobar bronchi) or has a minimal reduction in the airway caliber and contribution to the clinical signs and functional impairment.…”

“…However, the access to multiple airways may be limited due to the logistics of the examination and the effects of anesthetic drugs may alter the pattern of respiration [ 19 ]. Apnea or shallow breathing that is associated with general anesthesia in the absence of endotracheal intubation, as commonly performed in dogs during tracheobronchoscopy [ 20 ], may preclude the recognition or the severity of a dynamic AC [ 3 ]. In addition, studies comparing the diagnostic utility of I/E-BH CT to tracheobronchoscopy in dogs with an AC are lacking.…”

A One Health review of aerodigestive disease in dogs

“…Small airway diseases, affecting bronchioles <2 mm in diameter and lacking cartilage in their walls, have been described and classified in people and cats, 26,201 but are not well characterized in dogs 202‐206 . Dogs have no pathognomonic respiratory clinical signs.…”