Retrospective analysis of incidence, clinical features, potential risk factors, and prognostic indicators for aspiration pneumonia in three brachycephalic dog breeds

In-hospital mortality in dogs with protein-losing enteropathy and associated risk factors

BACKGROUND

Risk factors associated with negative outcomes in dogs with protein-losing enteropathy (PLE) are well documented. However, mortality before hospital discharge and associated risk factors are not well described.

HYPOTHESIS/OBJECTIVES

Report the percentage of dogs with PLE that do not survive to hospital discharge and identify associated risk factors.

ANIMALS

One-hundred and seven dogs presented to a referral hospital and diagnosed with PLE caused by inflammatory enteritis, intestinal lymphangiectasia or both.

METHODS

Retrospective cross-sectional study assessing hospital records. Data on in-hospital mortality and cause were assessed, and presenting signs, treatments prescribed, neutrophil count, lymphocyte count, serum albumin, globulin, and C-reactive protein (CRP) concentrations, and histopathologic findings were compared between survivors and non-survivors.

RESULTS

In-hospital mortality was 21.5% with the most common causes including financial limitations, failure to improve and aspiration pneumonia. Factors associated with mortality during hospitalization included longer duration of hospitalization (P = .04), longer duration of clinical signs (P = .02) and an increase in serum CRP concentration after 1-3 days of in-hospital treatment (P = .02). Higher mortality was identified in Pugs (odds ratio [OR], 4.93; 95% confidence interval [CI], 1.41-17.2; P = .01) and was a result of presumptive aspiration pneumonia in 5/6 of these dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Protein-losing enteropathy in dogs has substantial mortality during hospitalization. Monitoring for improvement in CRP concentration after treatment during hospitalization may help predict survival to discharge. Pugs have increased in-hospital mortality because of aspiration pneumonia; measures to prevent, recognize, and promptly treat this complication may improve outcomes in this breed.

Recognition and Diagnosis of Underlying Disease Processes in Bacterial Pneumonia

Bacterial pneumonia can present in both dogs and cats as either acute or chronic disease, and clinical signs may suggest respiratory or systemic impairment. Aspiration pneumonia, a common form of disease, can be caused by esophageal or laryngeal disease, vomiting, or altered mentation, such as with CNS disease or general anesthesia. Bacterial pneumonia can also develop due to inhaled airway foreign bodies, reduced local immune function, or impaired clearance of respiratory secretions. Rapid identification of the etiology and associated risk factors for pneumonia can help veterinarians develop a targeted therapeutic plan and prevent recurrence of disease.

Risk factors for complicated perioperative recovery in dogs undergoing staphylectomy or folded flap palatoplasty: Seventy-six cases (2018-2022)

OBJECTIVE

To analyze risk factors for complicated perioperative recovery of dogs undergoing either staphylectomy or folded flap palatoplasty.

STUDY DESIGN

Retrospective study.

ANIMALS

Seventy-six client-owned dogs.

METHODS

Medical records of dogs that underwent either staphylectomy or folded flap palatoplasty were reviewed for signalment, brachycephalic risk (BRisk) score, history of gastrointestinal signs, laryngeal collapse grade, presence of preoperative aspiration pneumonia, intraoperative respiratory and cardiovascular complications, length of general anesthesia, number of corrected brachycephalic obstructive airway syndrome (BOAS) components, and gastrointestinal and respiratory postoperative complications. Complicated recovery was defined as requirement for prolonged oxygen treatment and/or tracheostomy or perioperative death. Penalized logistic regression was used to identify risk factors.

RESULTS

Seventy-six dogs were enrolled in the study. Multivariate penalized logistic regression identified four risk factors for complicated recovery. These include surgery type (p = .0002), age (p = .0113), laryngeal collapse grade >2 (p < .0001) and length of general anesthesia (p = .0051).

CONCLUSIONS

In this population, dogs that had staphylectomy, increasing age, laryngeal collapse grade >2 and increasing length of general anesthesia were at increased risk for perioperative complicated recovery.

CLINICAL SIGNIFICANCE

The results of this study identified risk factors for perioperative complicated recovery in dogs undergoing elongated soft palate correction and may assist in surgical planning and early prediction of complications.

Complications and outcome following staphylectomy and folded flap palatoplasty in dogs with brachycephalic obstructive airway syndrome

OBJECTIVE

To compare the prevalence of pre-, intra-, and postoperative variables and complications associated with staphylectomy (S) and folded flap palatoplasty (FFP).

STUDY DESIGN

Retrospective study.

SAMPLE POPULATION

Client-owned dogs (n = 124).

METHODS

Medical records of S and FFP dogs from a veterinary teaching hospital were reviewed between July 2012 and December 2019. Signalment, clinical pre-, intra-, and postoperative data were collected and reviewed. Median (interquartile range) was reported.

RESULTS

A total of 124 dogs among 14 breeds underwent surgical treatment for an elongated soft palate with either a S (n = 64) or FFP (60). FFP dogs without concurrent non-airway procedures were associated with longer duration of surgery (p = .02; n = 63; S, median = 51 min [34-85]; FFP, median = 75 min [56.25-94.5]) and anesthesia (p = .02; n = 63; S, median = 80 min [66-125]; FFP, median = 111 min [91-140.8]). Neither soft palate surgery was associated with the occurrence of anesthetic complications (p = .30; 99/120; S, 49; FFP, 50), postoperative regurgitation (p = .18; 27/124; S, 17; FFP, 10), or with hospitalization duration (p = .94; n = 124; S, median = 1 day [1]; FFP, median = 1 [1]). Postoperative aspiration pneumonia (9/124; S, 4; FFP, 5) and major complications were rare (5/124; S, 3; FFP, 2).

CONCLUSION

S and FFP had similar anesthetic and perioperative complications, although FFP dogs had longer anesthetic and operative times.

CLINICAL SIGNIFICANCE

Although FFP took longer, no other clinically significant differences were appreciated between S and FFP procedures. Because of limitations inherent in study design, surgeons should continue to use clinical judgment when deciding on a procedure.

Respiratory compromise in French bulldogs presented with intervertebral disc extrusion

BACKGROUND

French bulldogs hospitalised for the management of intervertebral disc extrusion (IVDE) are frequently affected by respiratory compromise, typically brachycephalic-associated upper respiratory obstruction and/or aspiration events. We evaluated the occurrence of such respiratory compromise events in French bulldogs presented to two referral hospitals.

METHODS

Clinical data for French bulldogs diagnosed with IVDE were retrospectively collated, including severity of neurological deficits, neuroanatomical localisation, diagnosis, details of respiratory compromise, treatment and outcome.

RESULTS

A total of 306 dogs diagnosed with IVDE were included. Sixty dogs (19.6%) experienced respiratory compromise, of which 31 dogs (10.1%) progressed to cyanosis, collapse or respiratory arrest.

LIMITATIONS

The study was limited by its retrospective nature. Furthermore, the duration of hospitalisation was not evaluated and the decision for euthanasia was often multifactorial.

CONCLUSION

One in five French bulldogs presented with IVDE experienced respiratory compromise. The detrimental welfare effects of this warrant further discussion.

A Review of Clinical Outcomes, Owner Understanding and Satisfaction following Medial Canthoplasty in Brachycephalic Dogs in a UK Referral Setting (2016-2021)

Brachycephalic breeds have increased in popularity despite growing awareness of their predisposition to a wide range of conformation-related diseases. The extreme facial conformation of many popular brachycephalic breeds compromises their ocular surface health, increasing the risk of painful corneal ulceration. Medial canthoplasty (MC) is a surgical procedure to address ocular abnormalities in brachycephalic dogs, which are collectively referred to as brachycephalic ocular syndrome (BOS). This study retrospectively reviewed the records of dogs recommended MC at a referral hospital between 2016 and 2021. A questionnaire was designed to identify owners' perceptions pre- and post-operatively. From 271 brachycephalic dogs recommended MC, 43.5% (118/271) underwent surgery and 72.0% (85/118) were Pugs. The majority of dogs (73.7%, 87/118) that underwent surgery had current or historical corneal ulceration. Follow-up was available in 104 dogs, of which 5.7% (6/104) had corneal ulceration post-operatively. Sixty-four owners completed the questionnaire and reported post-operative corneal ulceration in 12.5% of dogs (8/64), reduced ocular discharge (70.8%, 34/48), reduced ocular irritation (67.7%, 21/31) and less periocular cleaning (52.5%, 32/61). Owners were satisfied with the clinical (85.9%, 55/64) and cosmetic (87.5%, 56/64) outcome. In conclusion, MC has high clinical relevance for the surgical management of BOS, restoring functional conformation and improving the quality of life of affected dogs.

A retrospective study on parapneumonic effusion in 130 dogs with a clinical diagnosis of pneumonia

Objective

To screen the occurrence of parapneumonic effusion in dogs.

Methods

Medical records were searched for dogs with a presumptive diagnosis of bacterial pneumonia from 2017 to 2021 at the Liege university teaching hospital. Bacterial pneumonia was presumptively diagnosed based on compatible clinical signs and findings; thoracic radiographs compatible with bacterial bronchopneumonia; and either increased serum C-reactive protein (CRP) levels, a positive bronchoalveolar lavage culture or a positive clinical evolution in response to antibiotic therapy. Patients diagnosed with parasitic or other non-bacterial inflammatory pneumonia or with pulmonary neoplasia were excluded. Signalment, clinical findings, and outcome were recorded.

Results

One hundred and thirty dogs were included in the study, of which 44 dogs (33.8%) developed a parapneumonic effusion. Four of these dogs (4/44; 9%) had thoracocentesis performed, displaying a modified transudate (2) or septic exudate (2).

Conclusions

Although parapneumonic effusion in dogs with a presumptive diagnosis of bacterial pneumonia appears to be rather common (33.8%), thoracocentesis or chest tube placement was rarely performed. Furthermore, the outcome of dogs with and without parapneumonic effusion appears to be similar.

Computed tomographic findings in dogs with suspected aspiration pneumonia: 38 cases (2014‐2019)

OBJECTIVES

To describe computed tomographic (CT) findings in dogs diagnosed with aspiration pneumonia and to assess for any correlation with patient outcome.

MATERIALS AND METHODS

Retrospective analysis of 38 cases with a presumptive diagnosis of aspiration pneumonia at two UK referral centres. Medical records were reviewed for signalment, history, physical examination and clinicopathologic data. CT examinations of the thorax were reviewed by the European College of Veterinary Diagnostic Imaging board-certified radiologist for all dogs to describe the characteristics and distribution of the pulmonary lesions.

RESULTS

The most common CT findings were lung lobe consolidation associated with air bronchograms (100%) followed by ground-glass attenuation (89.4%), bronchial wall thickening (36.8%), bronchiolectasis (31.5%) and bronchiectasis (15.7%). Large-breed dogs were overrepresented. Duration of hospitalisation ranged between 0 and 8 days (mean 3 days). Overall, 89.4% of dogs survived the aspiration event and were discharged from the hospital. The four dogs that did not survive to discharge had five or more lobes affected on CT.

CLINICAL SIGNIFICANCE

CT findings in dogs with aspiration pneumonia are described. CT is a useful imaging modality to diagnose aspiration pneumonia.

A Comparative Assessment of the Diagnosis of Swallowing Impairment and Gastroesophageal Reflux in Canines and Humans

Swallowing impairment is a highly prevalent and clinically significant problem affecting people and dogs. There are myriad causes of swallowing impairment of which gastroesophageal reflux is the most common in both species. Similarities in anatomy and physiology between humans and canines results in analogous swallowing disorders including cricopharyngeus muscle achalasia, esophageal achalasia, hiatal herniation, and gastroesophageal reflux with secondary esophagitis and esophageal dysmotility. Accordingly, the diagnostic approach to human and canine patients with swallowing impairment is similar. Diagnostic procedures such as swallowing fluoroscopy, high-resolution manometry, pH/impedance monitoring, and endolumenal functional luminal imaging probe can be performed in both species; however, nasofacial conformation, increased esophageal length, and the difficulty of completing several of these procedures in awake dogs are inherent challenges that need to be considered. Human patients can convey their symptoms and respond to verbal cues, whereas veterinarians must rely on clinical histories narrated by pet owners followed by comprehensive physical examination and observation of the animal eating different food consistencies and drinking water. Dogs may also be unwilling to drink or eat in the hospital setting and may be resistant to physical restraint during diagnostic procedures. Despite the species differences and diagnostic challenges, dogs are a natural animal model for many oropharyngeal and esophageal disorders affecting people, which presents a tremendous opportunity for shared learnings. This manuscript reviews the comparative aspects of esophageal anatomy and physiology between humans and canines, summarizes the diagnostic assessment of swallowing impairment in both species, and discusses future considerations for collaborative medicine and translational research.

Clinical use of a new frameless optical neuronavigation system for brain biopsies: 10 cases (2013-2020)

OBJECTIVES

The aim of the retrospective study was to describe the brain biopsy procedure using a new frameless optical neuronavigation system and to report diagnostic yield and complications associated with the procedure.

MATERIALS AND METHODS

The medical records for all dogs with forebrain lesions that underwent brain biopsy with a frameless optical neuronavigation system in a single referral hospital between 2013 and 2020 were retrospectively analysed. Following data were collected: signalment, neurological signs, diagnostic findings, number of brain biopsy samples, sampled region, complications, duration of hospitalisation, whether the samples were diagnostic and histopathological diagnoses. The device consists of a computer workstation with navigation software, an infrared camera, patient tracker and reflective instruments. The biopsy needle was equipped with reflective spheres, so the surgeon could see the position of the needle during sampling the intracranial lesion free handed through a mini-burr hole.

RESULTS

Ten dogs were included. Absolute diagnostic yield based on specific histopathological diagnosis was 73.9%. Three dogs had immune-mediated necrotizing encephalitis, two dogs showed a necrotizing leukoencephalitis and two dogs a meningoencephalitis of unknown origin. In two dogs, the brain specimen showed unspecific changes. In one dog, the samples were non-diagnostic. Seven dogs showed no neurological deterioration, one dog mild temporary ataxia and two dogs died within 36 hours post brain biopsy.

CLINICAL SIGNIFICANCE

In these 10 dogs, the frameless optical neuronavigation system employed was useful to gain diagnostic brain biopsy samples. Considering the mortality rate observed, further studies are needed to confirm the safety of this procedure and prove its actual clinical effectiveness.

Circumferential esophageal hiatal rim reconstruction for treatment of persistent regurgitation in brachycephalic dogs: 29 cases (2016-2019)

OBJECTIVE

To describe a technique for circumferential esophageal hiatal rim reconstruction and to report outcomes in brachycephalic dogs with persistent regurgitation treated with the technique.

ANIMALS

29 client-owned brachycephalic dogs.

PROCEDURES

Dogs that had undergone circumferential esophageal hiatal rim reconstruction between January 1, 2016, and December 31, 2019, for treatment of persistent regurgitation were identified through a search of the medical record database of The Animal Hospital at Murdoch University. Circumferential esophageal hiatal rim reconstruction involved apposition of the medial margins of the left and right pars lumbalis dorsal to the esophagus (reconstructing the dorsal margin) and ventral to the esophagus (reducing the ventral hiatal aperture and completing the circumferential reconstruction). Data collection from the medical records included preoperative, intraoperative, and postoperative (short- and long-term outcomes [≤ 14 days and ≥ 6 months, respectively]) data.

RESULTS

In all dogs, substantial laxity of the left and right pars lumbalis and failure of dorsal coaxial alignment were observed, and circumferential esophageal hiatal rim reconstruction and esophagopexy were performed. Results of short-term follow-up indicated reduced regurgitation frequency; however, 7 of 29 dogs continued to have mild regurgitation, which was attributed to esophagitis and resolved with medical management. Long-term follow-up information was available for 19 dogs: regurgitation had resolved in 16 dogs and occurred once weekly in 3 dogs. No ongoing medication was required for any dog.

CONCLUSIONS AND CLINICAL RELEVANCE

Circumferential hiatal rim reconstruction combined with esophagopexy substantially reduced regurgitation frequency in dogs of the present study, and we recommend that this procedure be considered for brachycephalic dogs presented with a history of regurgitation unresponsive to medical management.