Computed tomographic assessment of principal bronchial anatomy in dogs of various thoracic conformations: 93 cases (2012-2017).

OBJECTIVE: To better understand spatial relationships between principal bronchi and other intrathoracic structures by use of CT images of dogs of various somatotypes. ANIMALS: 93 dogs that underwent thoracic CT. PROCEDURES: Information was collected from medical records regarding signalment and physical examination and echocardiographic findings. Two investigators recorded multiple measurements on a thoracic axial CT image from each dog. RESULTS: Thoracic height-to-width ratio (H:W) was associated with left principal bronchus (LPB) and right principal bronchus (RPB) H:W, aortic-LPB separation, focal LPB narrowing, and aortic-vertebral overlap. Thoracic H:W was not associated with dog age, weight, sex, or brachycephalic breed. Twenty-five (27%) dogs had focal LPB narrowing, compared with 5 (5%) dogs with focal RPB narrowing (P < 0.001). Ten of 25 dogs had overlap or contact between vertebrae, aorta, LPB, and heart, suggesting a cumulative compressive effect on the LPB, while 15 had LPB-aorta contact and lack of contact between the aorta and thoracic vertebrae, suggesting an aortic constrictive effect on the LPB. None had LPB narrowing without contact from surrounding structures. Inter-rater agreement was high. CLINICAL RELEVANCE: In dogs that underwent CT and were not selected for clinical suspicion of bronchial disease, principal bronchial morphology was associated with thoracic conformation. Focal LPB narrowing occurred more often than RPB narrowing. Focal LPB narrowing occurred with evidence of extraluminal compression, with or without contact between aorta and vertebrae. Brachycephalic breed could not be used for predicting thoracic H:W.

Comparison of short-, intermediate-, and long-term results between dogs with tracheal collapse that underwent multimodal medical management alone and those that underwent tracheal endoluminal stent placement.

OBJECTIVE: To compare short-, intermediate-, and long-term results between dogs with tracheal collapse (TC) that received multimodal medical management only and those that underwent tracheal endoluminal stent placement. ANIMALS: 159 dogs with TC that underwent medical management only (MM group; n = 84) or were surgically managed by stent placement (SM group; 75). PROCEDURES: Medical records of dogs with TC that underwent medical management only or stent placement at a referral hospital between September 1, 2009, and August 1, 2018, were reviewed. Data regarding signalment, information relevant to TC, and outcome were extracted from the records and aggregated into short-, intermediate-, and long-term follow-up periods for analysis. Descriptive data and median survival times (MSTs) were compared between the MM and SM groups. RESULTS: Clinical signs of dogs in the MM group generally improved during the short term but regressed and worsened over time. The proportion of dogs with malformation-type TC that underwent stent placement (38/43 [88%]) was significantly greater than the proportion of dogs with traditional-type TC that underwent stent placement (37/107 [35%]). The MST from TC diagnosis was 3.7 years for the MM group and 5.2 years for the SM group. For dogs with severe disease, the MST was 12 days for medically managed dogs and 1,338 days for dogs that underwent stent placement. CONCLUSIONS AND CLINICAL RELEVANCE: Multimodal medical management alleviated clinical signs for months to years in dogs with mild to moderate TC disease, but stent placement should be considered for dogs with severe disease.

Bacterial infection before and after stent placement in dogs with tracheal collapse syndrome.

BACKGROUND: Dogs with tracheal stents often have positive airway bacterial cultures. The pathogenicity of these organisms and risk factors for infection have not been investigated. OBJECTIVE: Describe bacterial infection in dogs with tracheal collapse before and after tracheal stent placement. ANIMALS: Fifty-three client-owned dogs. METHODS: Retrospective review of medical records of dogs receiving tracheal stents with thoracic radiographs, tracheoscopy, and endotracheal lavage. RESULTS: There was no difference between the overall prevalence of dogs with positive bacterial cultures before (31/38; 82%) or after stent placement (24/31; 77%) (P = .67). An increased number of geriatric (17/28; 61%) and traditional-type collapse (TTC) (16/26; 62%) dogs had positive pathogenic airway infections before stent placement, compared to young (8/25; 32%; P = .04) and malformation-type collapse (MTC) dogs (9/27; 33%; P = .04). After tracheal stent placement, geriatric dogs had a 52% reduction in pathogenic bacteria infection frequency (P = .02) and dogs with TTC had a 56% reduction in pathogenic bacteria infection frequency (P = .01). Significant risk factors for pathogenic infection included a history of pneumonia (OR = 3.6; 95% CI, 0.28-43.36) and cardiac disease (OR = 1.25; 95% CI, 0.16-9.92) in geriatric dogs, and hepatomegaly in young dogs (OR = 1.5; 95% CI, 0.12-19.44). CONCLUSIONS AND CLINICAL IMPORTANCE: Tracheal stent placement does not increase the overall rate of pathogenic bacterial infection in dogs with tracheal collapse and can decrease the rate of subsequent pathogenic infections in geriatric dogs and dogs with TTC that require tracheal stenting. Airway culture and cytology should be performed in all dogs undergoing tracheal stent placement.

Interventional treatment of benign nasopharyngeal stenosis and imperforate nasopharynx in dogs and cats: 46 cases (2005-2013).

OBJECTIVE To determine outcome for dogs and cats with benign nasopharyngeal stenosis or an imperforate nasopharynx that underwent balloon dilatation or metallic stent placement. DESIGN Retrospective case series. ANIMALS 15 dogs and 31 cats. PROCEDURES Medical records were retrospectively reviewed, and data on signalment, history, clinical signs, lesion location, treatment, and outcome were obtained. Patients were excluded if < 6 months of follow-up information was available. RESULTS 5 dogs and 22 cats underwent balloon dilatation, and results were successful in 11 (0 dogs and 11 cats) of the 27 (41%). Stents were placed in 34 patients (including 15 in which balloon dilatation had been unsuccessful). Uncovered stents were placed in 30 patients, and results were successful in 20 (67%). Covered stents were placed in 11 patients (including 7 in which uncovered stent placement was unsuccessful), and results were successful in all 11. Twenty-three of the 34 (68%) patients in which stents were placed developed complications. The most common complications were tissue ingrowth (n = 10), chronic infection (7), and stent fracture (5) for the 30 patients with uncovered stents and chronic infection (8) and oronasal fistula (3) for the 11 patients with covered stents. Overall, outcome was successful in 36 of the 46 (78%) patients (median follow-up time, 24 months; range, 2 to 109 months). CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that in dogs and cats, nasopharyngeal stenosis and imperforate nasopharynx can be successfully treated with balloon dilatation or stent placement, but that there was a high risk of failure with balloon dilatation alone and a high risk of complications regardless of procedure.

Effect of cross-match on packed cell volume after transfusion of packed red blood cells in transfusion-naïve anemic cats.

BACKGROUND: Novel feline RBC antigens might contribute to decreased efficacy of RBC transfusion and increased incidence of acute transfusion reactions (ATR). OBJECTIVES: To examine the effect of major cross-match in transfusion-naïve anemic cats on the incidence of acute immunologic transfusion reaction and transfusion efficacy for up to 24 hours after transfusion. ANIMALS: Forty-eight client owned transfusion-naïve anemic cats. METHODS: Prospective, randomized, controlled study. All transfusion-naïve cats receiving packed red blood cells (pRBC) transfusions from January 2016 to August 2017 were eligible for inclusion. Cats in the study group received cross-match and blood type compatible pRBCs and cats in the control group received noncross-matched blood type compatible pRBCs. Incidence of ATR and change in PCV after transfusion was recorded. RESULTS: No significant difference in incidence of transfusion reactions between cross-matched and noncross-matched groups (CM+ 4/24; 17%, CM- 7/24; 29%, P = .16). No significant difference between groups in mean change in PCV after transfusion scaled to dose of pRBCs administered at any time point after transfusion (immediate: CM+ 0.62 ± 0.59, CM- 0.75 ± 0.48, P = .41; 1 hour: CM+ 0.60 ± 0.66, CM- 0.74 ± 0.53, P = .43; 12 hours: CM+ 0.70 ± 0.55, CM- 0.66 ± 0.60, P = .81; 24 hours: CM+ 0.64 ± 0.71, CM- 0.55 ± 0.48, P = .70). CONCLUSIONS AND CLINICAL IMPORTANCE: Our results do not support use of the major cross-match test to increase efficacy of, and to decrease adverse events associated with, RBC transfusion in AB blood typed transfusion-naïve cats.