How To Manage Cases of BOAS
It was only a few weeks ago when the BBC highlighted the suffering endured by some of the increasingly popular brachycephalic breeds of dog as a result of their extreme facial anatomy. I was pleased to see it was one of the most read BBC stories of the day, and I hope it will have educated many dog owners about the problems faced by these ever popular breeds. Currently vets are seeing these brachycephalic dogs with increased frequency and Jane Ladlow, European Specialist in Small Animal Surgery, discussed how she would assess and manage cases of Brachycephalic Obstructive Airway Syndrome (BOAS) within last week’s coffee morning webinar at Cambridge University.
Jane’s discussion centred around the three most commonly encountered brachycephalic breeds, the bulldog, French bulldog and pug, and explained that each breed had different features contributing to their BOAS. For example, bulldogs are more likely to have pharyngeal lesions which include an over long soft palate and hypertrophied tonsils. These malformations lead to a difficulty in swallowing and breathing and affected bulldogs often have a low pitch respiratory noise. Pugs are more likely to have laryngeal lesions which cause inspiratory distress and produce a higher pitched noise centred around their larynx. Finally the French bulldog is more likely to have nasal deformities leading to stertor which is a low pitched noise originating from the nose.
Endoscopy, rhinoscopy and CT evaluation were all diagnostics discussed within this webinar proving useful alongside history and physical examination for diagnosing BOAS. Jane also performs whole body barometric plethysmography (WBBP) on her patients which is available at Cambridge University and helps to measure a number of parameters used to assess BOAS within an individual in a non-stressed environment. These parameters, alongside results from a three minute exercise tolerance test, help to determine a measure known as the BOAS index which helps score the severity of the condition within an affected patient.
Jane has been able to obtain this BOAS index data from a number of breeds to help determine the prevalence of BOAS in pugs, French bulldogs and bulldogs. From the data obtained, it was found that 60% of pugs, 46% of French bulldogs and, perhaps somewhat surprisingly, 40% of bulldogs are suffering with BOAS. She was also able to determine that being overweight played a very important factor in the severity of BOAS in pugs but less so in French bulldogs and bulldogs. She also found that 90% of dogs affected by BOAS had stenotic nostrils.
Secondary changes which occur as a result of BOAS were also discussed and included the development of a sliding hiatus hernia, oesophageal reflux and sleep apnoea. Oesophageal reflux develops as a result of breathing in excess air which causes distension of the stomach, leading to gastrin release and hyperacidity. Jane advises over 80% of these cases should settle down once surgery had been performed to correct their BOAS. Sleep apnoea is more often seen in French bulldogs and bulldogs where they enter a deep sleep only to be interrupted by sleep apnoea multiple times a night. This could have a real impact on a patient’s quality of life and interestingly Jane placed monitors on patients before and after they had corrective surgery only to find that treated patients became significantly less active at night presumably because their sleep apnoea had resolved.
The surgical correction of patients suffering from BOAS was discussed with Jane outlining a number of modern surgical techniques explained through videos and pictures which can only be really appreciated by watching this webinar. Given that BOAS is such a vast subject matter to cover, the amount of information delivered within the space of half an hour was quite incredible. If you want an update on this hot topic and time is precious (and let’s face it when is it not) then last week’s webinar led by Jane should offer you all you need to know and a bit more!