Gastric dilation-volvulus in dogs attending UK emergency-care veterinary practices: prevalence, risk factors and survival

Pet health insurance reduces the likelihood of pre-surgical euthanasia of dogs with gastric dilatation-volvulus in the emergency room of an Australian referral hospital

AIMS

To determine the association between the presence of pet health insurance and the risk of euthanasia at the time of diagnosis for dogs with gastric dilatation-volvulus (GDV).

METHODS

Insurance status at the time of GDV diagnosis was sought for a cohort of 147 non-referred, confirmed cases of GDV that presented to the emergency department of a university-based veterinary hospital in Australia between 2008 and 2017. Insurance status was obtained from the medical record (n=18) or after contacting the owners by phone using a standardised questionnaire (n=129). Animal, clinical and outcome data was retrospectively compiled in a research database. The primary outcome measure was whether or not the dog was euthanised before surgery. The Mantel-Haenszel procedure was used to quantify the association between the presence of pet health insurance and the risk of euthanasia at the time of diagnosis for dogs with GDV, adjusting for the confounding effect of age at the time of presentation using Bayesian methods.

RESULTS

Of the 69 dogs for which insurance information could be obtained, 10 (14%) cases were insured at the time of the GDV event and 59 (86%) cases were not. The majority of non-insured dogs (37/59; 63 (95% CI=50-74)%) were euthanised before surgery, while none (0 (95% CI=0-28)%) of the insured dogs were euthanised at that time (p<0.001). Of the 32 insured and non-insured dogs that underwent surgery, four dogs (13 (95% CI=5-28)%) did not survive to hospital discharge. Three dogs (9%) were euthanised during or after surgery and one dog (3%) experienced cardiopulmonary arrest during treatment. The majority of dogs for which insurance status was known did not survive to hospital discharge (41/69; 59%), and 90 (95% CI=7-96)% of deaths were caused by euthanasia prior to surgery. Uninsured dogs were 5.0 (95% credible interval=1.8-26) times more likely to undergo presurgical euthanasia compared with insured dogs.

CONCLUSIONS

Euthanasia prior to treatment was most common cause of death in non-referred dogs with GDV; such euthanasia was entirely absent in the cohort of dogs that were insured.

CLINICAL RELEVANCE

Financial considerations significantly contribute to mortality of dogs with GDV presented to an emergency room. Financial instruments to reduce the out-of-pocket expense for pet owners confronted with unexpected veterinary expenses have potential to reduce pet mortality.

The Effect of Pet Insurance on Presurgical Euthanasia of Dogs With Gastric Dilatation-Volvulus: A Novel Approach to Quantifying Economic Euthanasia in Veterinary Emergency Medicine

Euthanasia of companion animals in veterinary emergency medicine is a common cause of death. Euthanasia is economic when it is the consequence of the pet owner's inability to afford essential treatment while a viable medical alternative to euthanasia exists. Gastric dilatation-volvulus (GDV) is an acute life-threatening emergency condition of dogs; if left untreated, rapid death is highly likely. Surgical treatment leads to survival of around 80-90% of dogs; however, such treatment is costly. Therefore, pre-surgical euthanasia may be largely economically motivated. Having pet insurance, a financial instrument to reduce the burden of unforeseen veterinary medical costs on pet owners, would be expected to abolish the risk for pre-surgical economic euthanasia. We therefore aimed to determine whether pet insurance attenuates the risk of pre-surgical economic euthanasia in dogs with GDV. Non-referred dogs (n = 260) with GDV and known insurance status seen at 24 emergency clinics over a 2-year period were included. Relevant data (e.g., insurance status, age, comorbidities, outcome) were retrospectively extracted from a pet insurer's claim records (insured animals) or from electronic medical records of participating hospitals (non-insured animals). Forty-one percent of dogs (106 of 260 dogs) did not survive to hospital discharge; 82 (77%) of non-survivors died before surgery, all through euthanasia. The pre-surgical euthanasia rate was 10% in insured and 37% in non-insured dogs (p < 0.001). When adjusted for the effect of age, deposit size, comorbidities, and blood lactate concentration, the absence of insurance increased the odds of pre-surgical euthanasia by a factor of 7.4 (95% CI 2.0 to 37; p = 0.002). Of dogs undergoing surgery, 86% survived to hospital discharge. Overall, 80% of insured animals and 53% of non-insured animals survived to hospital discharge (p < 0.001). Thus, insurance was associated with a marked decrease in risk of pre-surgical euthanasia indicating that the cause of pre-surgical euthanasia of dogs with GDV is predominantly economic in nature. The rate of pre-surgical euthanasia in dogs with GDV may emerge as a suitable marker to quantify economic decision making of pet owners and to measure the impact of financial interventions aimed at mitigating economic duress associated with cost of veterinary emergency care.

Identification of Genetic Susceptibility Factors Associated with Canine Gastric Dilatation-Volvulus

Canine gastric dilatation-volvulus (GDV) is a common life-threatening condition occurring primarily in large and giant breeds with a 3.9% to 36.7% lifetime risk. The genetic correlates of GDV have not previously been systematically explored. We undertook an inter-breed genome-wide association analysis (GWAS) of 253 dogs from ten breeds including 106 healthy dogs and 147 dogs with at least one GDV episode. SNP array genotyping followed by imputation was conducted on 241 samples to identify GDV-associated single-nucleotide polymorphisms (SNPs) and copy number variations (CNVs). A subset of 33 dogs (15 healthy dogs and 18 GDV patients from the three most represented breeds) was characterized by whole genome sequencing (WGS). After genome-wide Bonferroni correction, we identified a significant putatively protective intergenic SNP (rs851737064) across all breeds. The signal was most significant in Collies, German Shorthaired Pointers, and Great Danes. Subsequent focused analysis across these three breeds identified 12 significant additional putatively protective or deleterious SNPs. Notable significant SNPs included those occurring in genes involved in gastric tone and motility including VHL, NALCN, and PRKCZ. These data provide important new clues to canine GDV risk factors and facilitate generation of hypotheses regarding the genetic and molecular underpinnings this syndrome.

Lifespan of companion dogs seen in three independent primary care veterinary clinics in the United States

Background

The privately owned companion dog is an emerging model in comparative medicine, notably because it shares the human environment including its risk factors, is affected by many analogous age-related diseases, receives comparable medical care, and has excellent veterinary medical data available.

Past studies of dog lifespan have used academic, corporate or insurance data. While independent primary care data exist for the UK, none have as of yet been published for the US. This study analyzed data from three independent primary care US veterinary hospitals and identified factors that influence lifespan and mortality in a cohort of n = 20,970 privately owned dogs using Kaplan-Meier survival estimators and Cox Proportional Hazards modelling, including body size as a covariate.

Results

As previously reported, body size was negatively correlated with lifespan. Gonadectomy was associated with a longer lifespan, with the effect being stronger in females than in males. This lifespan advantage was conserved in gonadectomized female dogs that lived to at least ages 5 and 8 years. We did not find significant differences in lifespan between purebred and mixed breed dogs; however, breeds with larger effective population sizes and/or lower inbreeding coefficients had median survival times 3–6 months longer than breeds with smaller effective population sizes or higher inbreeding coefficients, indicating that these measures of genetic diversity may be affecting breed lifespans. We also found that dog breeds belonging to the “Mountain” ancestral group had median survival times that were 3.5–4.6 years shorter than other purebred dog groups, which remained significant even when correcting for body size.

Conclusions

Our findings show that it is possible to obtain and analyze data from independent veterinary clinics in the US, an approach that could be useful for studies of comparative epidemiology under the One Health and One Welfare paradigms. We also show that the lifespan effects of gonadectomy are not identical between the sexes and should be investigated separately by sex in future analyses. More research is needed to further clarify the influence of age at gonadectomy, as well as the factors leading to the observed differences in lifespan in the “Mountain” ancestral group and in dog breeds of varying inbreeding coefficients and effective population sizes.

Retrospective analysis of 736 cases of canine gastric dilatation volvulus

OBJECTIVE

To identify factors influencing the survival of confirmed gastric dilatation volvulus (GDV) cases presented to a specialist referral and emergency hospital.

METHODS

Clinical records of confirmed GDV cases admitted to two specialist referral and emergency centres in Sydney (Animal Referral Hospital (ARH) Homebush and ARH Baulkham Hills) between July 1999 and July 2019 were searched.

RESULTS

A total of 736 GDV cases were reviewed, of which 460 dogs were surgically treated and 276 dogs were humanely killed. The survival rates of patients operated on by general surgeons and specialists were 81.7% and 88.7%, respectively. Both incisional gastropexy and belt-loop gastropexy were clinically effective in treating GDV, with no significant difference in survival rates. Intraoperative mortality rates for general surgeons and specialists were 7.0% and 2.9%, respectively. The odds of mortality in dogs operated on by general surgeons were 2.03 times those operated on by specialist surgeons. The odds of mortality in dogs presented between 3:00 and 9:00 am were 3.57 times those of dogs presented between 9:00 am and 9:00 pm. The odds of mortality in dogs where the duration from presentation to completion of surgery was more than 3 h were 2.53 times those of dogs where time lapsed was equal or less than 3 h.

CONCLUSION

The results suggested that admission time was statistically significantly related to the survival rate. Dogs operated on by specialist surgeons had a significantly higher survival rate compared to those operated on by general surgeons. Clinicians should aim to stabilise and complete surgical correction of GDV as soon as possible to decrease the mortality.

The pattern of mortality in dogs with gastric dilatation and volvulus

INTRODUCTION

The primary study objective was to characterize the pattern of in-hospital mortality in dogs with gastric dilatation and volvulus (GDV), with a focus on preoperative nonsurvival.

MATERIALS AND METHODS

A retrospective review of medical records from a 10-year period was undertaken at a university teaching hospital. Data collected included signalment, physical examination parameters at hospital presentation, blood lactate concentration, and outcome.

RESULTS

A total of 498 dogs were included. Overall, 319 (64.1%) survived to discharge and 179 (35.9%) were nonsurvivors. Of the nonsurvivors, 149 (31.3% of all dogs) were euthanized and 30 (6%) died. Of those dogs euthanized, the majority (n = 116) were euthanized at the time of hospital presentation prior to surgery (ie, without intent to treat). When dogs that were euthanized prior to surgery were excluded, 83.5% of dogs survived to discharge. Median group age was higher in those euthanized than in the group of dogs that survived to discharge.

CONCLUSIONS

Preoperative euthanasia and hence nonsurvival without intent to treat accounted for the majority of GDV mortality in this study. Given the high rate of nonsurvival without intent to treat it is likely that efforts focused at disease prevention will ultimately affect a much greater improvement in overall disease mortality than those focused on improving treatment.

Pre- and post-surgical evaluation of plasma lactate concentration in 45 dogs with gastric dilatation-volvulus: A preliminary study

This preliminary study was designed to contribute to the evaluation of reliability of plasma lactate concentration (PLC) and its clearance as predictive and prognostic factors of gastric necrosis and clinical outcome of dogs affected by gastric dilatation-volvulus (GDV). Main aims of the study were: 1) to evaluate the prognostic reliability of PLC at presentation (T0) in dogs with GDV, 2) to compare the obtained data and considerations with the veterinary literature, and 3) to introduce the possible validity of PLC values at 24 (T24) and 48 (T48) hours after surgery as a predictive factor.

Dogs with GDV were retrospectively evaluated. PLC at T0, T24 and T48 were recorded and correlated to the presence or absence of macroscopic necrosis of the stomach and to outcome.

Forty-five dogs met the inclusion criteria. Significant differences were not detected in the mean values between the initial PLC in dogs with and without necrosis of the gastric wall, as well as between surviving and non-surviving dogs; these values were not associated with higher risk of gastric necrosis or death.

At T24 and T48 no significant differences were recorded between necrosis and non-necrosis, and surviving and non-surviving categories.

A median plasma lactate concentration clearance from arrival to T24 ≥ 50% was identified in both groups (with and without necrosis), and this parameter failed in identifying dogs that survived to discharge.

In conclusion, the results presented here failed to detect PLC at T0 and its clearance at T24 as prognostic factors in this population of dogs with GDV.

Longevity and mortality in Kennel Club registered dog breeds in the UK in 2014

Background

The domestic dog is one of the most diverse mammalian species, exhibiting wide variations in morphology, behaviour and morbidity across breeds. Therefore, it is not unexpected that breeds should also exhibit variation in mortality and longevity. While shorter longevity per se may not necessarily be a welfare issue, a generally foreshortened lifespan in a breed that is accompanied by a high prevalence of a particular cause of death may reveal potentially serious welfare concerns and highlight scope to improve breed welfare. Survey data gathered directly from owners offer useful insights into canine longevity and mortality that can support the overall evidence base for welfare reforms within breeds.

Results

Mortality data on 5663 deceased dogs registered with the UK Kennel Club were collected from an owner-based survey. The most commonly reported causes of death were old age (13.8%), unspecified cancer (8.7%) and heart failure (4.9%); with 5.1% of deaths reported as unknown cause. Overall median age at death was 10.33 years (interquartile range: 7.17–12.83 years). Breeds varied widely in median longevity overall from the West Highland Terrier (12.71 years) to the Dobermann Pinscher (7.67 years). There was also wide variation in the prevalence of some common causes of death among breeds, and in median longevity across the causes of death.

Conclusion

Substantial variation in the median lifespan and the prominent causes of death exists across breeds. This study has identified some breeds with both a low median lifespan and also a high proportional mortality for one or more specific causes of death that should be considered as both potential welfare concerns as well as opportunities for improvement.

Electronic supplementary material

The online version of this article (10.1186/s40575-018-0066-8) contains supplementary material, which is available to authorized users.

VetCompass Australia: A National Big Data Collection System for Veterinary Science

VetCompass Australia is veterinary medical records-based research coordinated with the global VetCompass endeavor to maximize its quality and effectiveness for Australian companion animals (cats, dogs, and horses). Bringing together all seven Australian veterinary schools, it is the first nationwide surveillance system collating clinical records on companion-animal diseases and treatments. VetCompass data service collects and aggregates real-time, clinical records for researchers to interrogate, delivering sustainable and cost-effective access to data from hundreds of veterinary practitioners nationwide. Analysis of these clinical records will reveal geographical and temporal trends in the prevalence of inherited and acquired diseases, identify frequently prescribed treatments, revolutionize clinical auditing, help the veterinary profession to rank research priorities, and assure evidence-based companion-animal curricula in veterinary schools. VetCompass Australia will progress in three phases: (1) roll-out of the VetCompass platform to harvest Australian veterinary clinical record data; (2) development and enrichment of the coding (data-presentation) platform; and (3) creation of a world-first, real-time surveillance interface with natural language processing (NLP) technology. The first of these three phases is described in the current article. Advances in the collection and sharing of records from numerous practices will enable veterinary professionals to deliver a vastly improved level of care for companion animals that will improve their quality of life.