ABSTRACT: This article explores respiratory problems in brachycephalic breeds thal have brachycephalic obstructive airway syndrome (BOAS), focussing on the English Bultdog. Findings from primary research highlight the congenital nature of BOAS in the English Bulldog, and suggest the need for reconstructive surgery early on in life.

Postoperatively. the percentage of dogs showing all degrees of improvement is shown to be consistently high Recent media interest has revealed a number of concerns from breeders, the general public, the Kennel Club and the veterinary profession. Amendments to breed standards are a necessity to prevent continued breeding of dogs with compromised airways.

This article is based on my dissertation which looked at brachycephalic dogs and the upper respiratory problems from which they suffer. The English Bulldog was the focussed breed and brachycephalic obstructive airway syndrome (BOAS) the primary respiratory disorder.

History of the Bulldog

Brachycephalic breeds, such as the English Bulldog, have unfortunately retained some undesirable traits as a consequence of breeding standards that have caused their head shape to change drastically and become distorted into the abnormal shape it is today. As a result they suffer from a number of respiratory problems.

Bulldogs were originally bred for bull- baiting – their head and body shape aiding them in the fierce and ferocious sport. Bull-baiting, which is thought to have taken place between the 13th and 18th centuries, began by using large mastiff dogs, but they proved too slow and cumbersome. Bulldogs were bred over a period of time as a breed that carried the majority of body weight near the head, ensuring that when the bull shook them they were less likely to break their backs.

In the 19th century, an Act of Parliament made bull-baiting illegal and as a consequence the number of Bulldogs decreased significantly. A group of individuals with an interest in the breed were able to protect it and, as a result, the first Bulldog club in the world – prior even to the Kennel Club – evolved.1

Welfare issues

The BBC’s programme Pedigree Dogs Exposed revealed a significant number of health issues in a variety of breeds, one of which was the English Bulldog.2 In the programme, a Bulldog breeder was interviewed and tried to justify the appearance and conformation of the dogs by referring back to the original purpose of the breed – bull-baiting.

The breeder claimed that the excess skin folds (known as flews) on their face were to channel the bull’s blood away from their eyes and nose and the receding nose meant that their breathing was not impeded whilst hanging on to a bull. The extension of the lower jaw aided them in grasping the bull’s muzzle more successfully than if both the maxilla and mandible were level.1

These anatomical deformities are, of course, no longer a requirement but are perpetuated by breeders who still conform to the breed standard.

It is imperative for us to recognise cases in which the welfare of the animal is no longer the main priority. In the case of breeding brachycephalic dogs, such as the Pekingese, Pug and Bulldog, it would appear that the health and welfare of these breeds has been discounted. Over time, the selective breeding of these dogs has become more focussed on cosmetic appearance in preference to anatomical soundness.

It is clear that the head shape is by no means suitable for the breed as evidenced by the need to provide assistance, both during mating and parturition. Breed standards obtained from the Kennel Club website for the English Bulldog have not been amended since 2003. Interestingly, the nostrils are described as large, wide and open. But despite this, a high number of Bulldogs are bred with stenotic nares.

Figure 1: The drastic change in the skull shape of the English Bulldog between 1890 and 1935

Literature review

The literature review demonstrated a higher incidence of brachycephalic obstructive airway syndrome in English Bulldogs in comparison with other brachycephalic breeds. All the papers calculated a mean age of occurance of less than three years for the English Bulldog – less than one year in a select few. The consistently younger age in this breed was unsurprising given the congenital nature of BOAS.

The literature also indicated the need for surgical intervention in order to improve the length and quality of life in brachycephalic breeds. Postoperatively, the percentage of dogs showing all degrees of improvement was consistently high. Combined airway surgery was also demonstrated to be the most beneficial approach.

A paper on hypoplasia of the trachea, published in 1992 by Coyne & Fingland, found the Bulldogs to be the most commonly affected breed and also that individuals are usually less than a year old at the time of diagnosis.3 If tracheal hypoplasia is the sole condition affecting the animal, it is often tolerated, but when associated with stenotic nares, elongated soft palate or everted saccules, the upper airway distress is exacerbated. The extent  to which the hypoplastic trachea gives rise to dyspnoea is inconclusive owing to other concurrent respiratory diseases.3

Figure 2: A Pug following widening of the stenotic nares – the left side having been widened and held together by a suture

In 1987, a study on sleep-disordered breathing in the Bulldog found evidence of sleep-disordered breathing being documented in seven English Bulldogs, all of which had a form of upper airway obstruction.4

The English Bulldog was over represented in these studies, highlighting breed prevalence for this condition. Surgery for stenotic nares or everted laryngeal saccules appears to be more effective when combined with soft palate resection. Soft palate resection alone would also appear to be successful.

Figures 3 & 4 illustrate the appearance before and after a soft palate resection.

Figures 3 & 4; Appearance before and after a soft palate resection

Nursing care for the brachycephalic patient

The intensive nursing care required for dyspnoeic patients can be challenging and time consuming.

Obesity may be an additional factor, as this will increase the strain on their respiratory system, particularly during any form of exercise; and weight regulation is an important aspect of client education and has been discussed in the research. Aspiration pneumonia was a predisposing factor for the dogs in one study – a preventive measure for which was weight loss.5

Conservative treatment of BOAS was discussed in a study and included, weight loss, keeping the animal cool, oxygen therapy and cage rest. Unfortunately, palliative methods do not eliminate the problem, so surgery is still highly recommended.6

Exercise intolerance was a common clinical sign for all dogs mentioned in the literature, a
nd this is exacerbated by obesity. Preoperative weight loss should, theoretically, improve recovery following corrective surgery and the veterinary nurse can play a significant role in facilitating this.

Brachycephalic patients requiring surgery are poor anaesthetic and postoperative risks.7 Preoperative examination highlighted two important factors to consider when handling brachycephalic patients – minimal restraint to prevent stress and access to oxygen therapy if cyanosis becomes apparent.

An oxygen cage is the preferred choice, as the inspired oxygen concentration can be closely controlled and is the least stressful method of administration.8 These patients routinely require arterial blood sampling to measure blood gas until normal readings are seen.8 Experience in correct sampling technique is a necessity, including the placement of arterial catheters to reduce stress to patient. Recognising signs of dyspnoea, such as open mouth breathing, are also essential; along with knowledge of tracheostomy tubes which may be used as a temporary measure if dyspnoea worsens.8

Figure 5 illustrates the positioning of the patient for surgery. The veterinary nurse must be competent at setting this up.

Figure 5: The positioning of the patient for surgery

The veterinary nurse should be confident in the interpretation and use of peri operative pulse oximetry and capnography to identify anomalies. Further improvements in surgical technique and peri-anaesthetic management will continue to reduce mortality rates following surgery and the veterinary nurse will play a critical role in the monitoring of anaesthesia.6

In the literature, the importance of postoperative critical nursing care for these patients was given great emphasis. Postoperative nursing care involves monitoring of vital parameters, particularly respiratory rate and core body temperature. Hypothermia prevention should be a standard precautionary measure following anaesthesia, and hyperthermia prevention owing to the tendency of brachycephalic patients to overheat.

Reduced volumes of food should be fed from a raised source. Additionally, monitoring levels of pain and exercise restriction are important nursing considerations. The poor confirmation of the airway means that constant observation is required for the first 48 hours postoperatively in order to minimise the occurrence of complications, such as gagging, vomiting and coughing, which could all lead to respiratory distress.

Finally, the literature stresses the importance of discussing the reoccurrence of clinical signs with owners, to avoid high expectations postoperatively.

Further research and education

The limited volume of papers in the literature would appear to indicate that further research should be implemented on BOAS. Despite being documented for over three decades, cases are still being referred to specialist surgeons for reconstructive surgery.

There is no doubt that surgical technique and critical nursing care could all be improved to prevent fatalities and improve postoperative recovery, but ideally the need for surgery needs to be eliminated.

Part of a veterinary nurses work is to act as an educational facilitator’ for the General Public and progressively to improve its realisation that there are trained people to help pet owners to understand more about their pets’ health and well-being. As a consequence, clients will better understand the role of the Veterinary Nurse.

Conclusion

It is not suggested that the English Bulldog should be banned as a breed, but strict breeding programmes must be developed to eliminate the anatomical and physiological abnormalities previously described. However, some would argue that the quality of life of these dogs is so compromised, that to ban breeding is the only way forward.9

Despite the availability of effective surgical techniques, prevention by means of responsible breeding is better than cure. 3

Author

Daniella Sines Bsc(Hons) RVNS

Daniella graduated as a veterinary nurse from the Royal Veterinary College, London, in July 2009, after completing a four-year degree programme. She developed a keen interest in referral nursing after spending many placements at the Queen Mother Hospital as a student, which subsequently led to her joining North Downs Specialist Referrals in September 2009. In her final year, she compiled a dissertation on brachycephalic obstructive airway syndrome.

To cite this article use either

DOI: 10.1111/j.2045-0648.2010.00022.x or Veterinary Nursing Journal Vol 26 pp 92-95

References

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2.   Pedigree dogs exposed one-off documentary televised on BBC1 on 19/08/2008,

3.   COYNE, B. E. and FINGLAND, R. B. 119921 Hypoplasia of the trachea in dogs: 103 cases [1974-19901' Journal of the American Veterinary Medical Association. 201 (5): 768-771,

4.   HENDRICKS, J. C.. KLINE. L. R„ KOVALSKI, R. J„ O'BRIEN, J. A.. MORRISON, A. R and PACK. A. I. (19871 The English Bulldog: a natural model of sleep-disordered breathing' American Physiological Society, pp1344-1350.

5.   L0RINS0N, D. and 8RIGHT, R. M [19971] Brachycephalic airway obstruction syndrome – a review of 118 cases' Canine Practice, 2215-61:18-21

6.   TORREZ, C, V. and HUNT. G. B. [2006] Results of surgical correction of abnormalities associated with brachycephalic airway obstruction syndrome in dogs in Australia’ Journal of Small Animal Practice 47: 150-154.

7.   FOSSUM, T. W. 120071 Small Animal Surgery, 3rd edition, China. Elsevier.

8.   TSENG. L. W. and WADDELL, L. S. [20001 Approach to the patient in respiratory distress' Topics in Companion Animal Medicine, 15121: 53-62.

9.   ROONEY, N, and SARGAN, D. (20091 Pedigree dog breeding in the UK: a major welfare concern? lonlinel, available from: http://www.rspca.org.uk/pedigreedogs, [accessed 06/04/091.

Veterinary Nursing Journal • Vol 26 • March 2011 •