Influence of thoracic conformation and genetics on the risk of gastric dilatation-volvulus in Irish setters

Outcomes and complications of prophylactic incisional gastropexy in 766 dogs (2009-2019)

OBJECTIVE

To report the outcomes and complications associated with prophylactic incisional gastropexy performed in dog breeds at risk for GDV.

RESULTS

Seven hundred and sixty-six dogs underwent prophylactic incisional gastropexy of which 61 were electively performed at the time of castration or spay and 705 were adjunctively performed at the time of emergency abdominal surgery. All dogs had short-term follow-up, and 446 dogs (58.2%) had additional follow-up with a median long-term follow-up time of 876 days (range 58-4450). Only 3 dogs (0.4%) had a direct complication associated with the gastropexy site including hemorrhage causing hemoabdomen (2) and infection with partial dehiscence (1). No dogs with long-term follow-up experienced gastric dilatation (GD), gastric dilatation volvulus (GDV), or persistent GI signs following gastropexy. Results of this study found that complications directly associated with prophylactic gastropexy were rare and limited to hemorrhage causing hemoabdomen and infection with partial dehiscence. Transient postoperative GI signs may occur. Gastropexy malpositioning and bowel entrapment were not encountered. There was no occurrence of GD or GDV.

Operational Canine

Operational K9s encompass a unique population of working dogs that serve as a force multiplier in various civilian law enforcement, force protection, search and rescue, and humanitarian operations. These elite canines do not volunteer to serve, yet they are some of the most faithful and dependable operators in the field. They undoubtedly perform an invaluable service in today's society and are owed a tremendous debt of gratitude for their selfless service, loyalty, and sacrifices. This article describes the unique characteristics and occupational hazards that pertain to the community of Operational K9s.

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.

CT findings in dogs with gastric malposition: 6 cases (2016-2019)

OBJECTIVES

To describe the computed tomographic (CT) findings of gastric malposition in a group of dogs with suspected chronic gastric instability.

MATERIALS AND METHODS

A multicentre retrospective study of CT studies of dogs with abnormal gastric position in the absence of clinical signs referable to gastric dilatation and volvulus.

RESULTS

Gastric malposition was identified in six dogs as either an incidental finding or in dogs with histories of chronic and intermittent gastroenteropathy. Gastric malposition was similar in all six cases; the pyloric canal was positioned in the left cranial abdomen in close proximity to the cardia and the pyloric antrum was found either to the left or ventral to the fundus.

CLINICAL SIGNIFICANCE

Recognition of gastric malposition as an incidental or chronic finding may prevent unnecessary emergency intervention on patients presenting for unrelated conditions.

Gastric dilatation and enterotoxemia in ten captive felids

CASE DESCRIPTION 10 large felids at 8 facilities were determined or suspected to have developed gastric dilatation with or without enterotoxemia over a 20-year period. Four felids were found dead with no premonitory signs. CLINICAL FINDINGS 4 felids (2 male snow leopards [Uncia uncia], 1 male Amur tiger [Panthera tigris altaica], and 1 male Sumatran tiger [Panthera tigris sumatrae]) were found dead or died before they could be evaluated. Six felids had hematemesis (1 male and 1 female African lion [Panthera leo] and 1 male jaguar [Panthera onca]) or abdominal distention and signs of lethargy with or without vomiting (1 male African lion, 1 male Malayan tiger [Panthera tigris jacksoni], and 1 female Sumatran tiger). Gastric dilatation was radiographically and surgically confirmed in the male Malayan and female Sumatran tigers and the jaguar. TREATMENT AND OUTCOME In 3 felids with an antemortem diagnosis, the gastric dilatation resolved with decompressive laparotomy but then recurred in 1 felid, which subsequently died. Three others died at various points during hospitalization. Although Clostridium perfringens type A was recovered from 3 of the 5 felids for which microbial culture was performed, and 2 felids had a recent increase in the amount fed, no single factor was definitively identified that might have incited or contributed to the gastric dilatation. CLINICAL RELEVANCE Gastric dilatation was a life-threatening condition in the large felids of this report, causing sudden death or clinical signs of hematemesis, abdominal distention, or vomiting. Even with rapid diagnosis and surgical decompression, the prognosis was poor. Research is needed into the factors that contribute to this emergent condition in large felids so that preventive measures might be taken.

Associations between gastric dilatation-volvulus in Great Danes and specific alleles of the canine immune-system genes DLA88, DRB1, and TLR5

OBJECTIVE To determine whether specific alleles of candidate genes of the major histocompatibility complex (MHC) and innate immune system were associated with gastric dilatation-volvulus (GDV) in Great Danes. ANIMALS 42 healthy Great Danes (control group) and 39 Great Danes with ≥ 1 GDV episode. PROCEDURES Variable regions of the 2 most polymorphic MHC genes (DLA88 and DRB1) were amplified and sequenced from the dogs in each group. Similarly, regions of 3 genes associated with the innate immune system (TLR5, NOD2, and ATG16L1), which have been linked to inflammatory bowel disease, were amplified and sequenced. Alleles were evaluated for associations with GDV, controlling for age and dog family. RESULTS Specific alleles of genes DLA88, DRB1, and TLR5 were significantly associated with GDV. One allele of each gene had an OR > 2 in the unadjusted univariate analyses and retained a hazard ratio > 2 after controlling for temperament, age, and familial association in the multivariate analysis. CONCLUSIONS AND CLINICAL RELEVANCE The 3 GDV-associated alleles identified in this study may serve as diagnostic markers for identification of Great Danes at risk for GDV. Additional research is needed to determine whether other dog breeds have the same genetic associations. These findings also provided a new target for research into the etiology of, and potential treatments for, GDV in dogs.

GASTRIC DILATATION VOLVULUS IN ADULT MANED WOLVES (CHRYSOCYON BRACHYURUS)

Gastric dilatation volvulus (GDV) was identified in six adult maned wolves ( Chrysocyon brachyurus ) housed at the Smithsonian Conservation Biology Institute in Front Royal, Virginia, and the Dickerson Park Zoo in Springfield, Missouri. Four individuals were found dead in their enclosures, and GDV was diagnosed postmortem based on radiographic and necropsy findings. Two individuals were diagnosed with GDV antemortem, with one wolf surviving following surgical intervention and supportive management. A concurrent splenic torsion was identified in three of six cases. Although GDV has been well documented in domestic dogs and is known to occur in maned wolves, objective, detailed case descriptions have been limited in this species. This report represents the first description of a surviving case of GDV in the maned wolf. Thorough species-specific documentation of any acutely fatal condition, such as GDV, is imperative for proper case recognition and medical management, with profound implications for species recovery efforts.

Efficacy of Incisional Gastropexy for Prevention of GDV in Dogs

Incisional gastropexy (IG) is routinely performed as either a prophylactic procedure to prevent occurrence of gastric dilatation-volvulus (GDV) or at the time of surgical correction of GDV to prevent recurrence. Despite its common use, the long-term efficacy of the IG procedure has not been reported. The hypothesis of this study was that IG performed either during surgical treatment of GDV or as a prophylactic measure would effectively prevent GDV. Medical records of 61 dogs undergoing IG following either gastric derotation for treatment of GDV or as a prophylactic procedure were evaluated retrospectively. Median follow-up time for all dogs was 717 days (range, 49–2,511 days). Of the 61 dogs, 27 had prophylactic IG performed. The remaining 34 dogs presented for GDV and had an IG performed during surgical treatment of GDV. No dog experienced GDV after IG. Recurrence of gastric dilatation (GD) alone was noted in 3 of 34 patients (8.8%) undergoing IG during surgery for GDV and in 3 of 27 patients (11.1%) treated prophylactically with IG. This study confirmed the efficacy of IG for the long-term prevention of GDV in dogs.

Evaluation of splenectomy as a risk factor for gastric dilatation-volvulus

OBJECTIVE

To evaluate whether dogs undergoing splenectomy had an increased risk of gastric dilatation-volvulus (GDV), compared with a control group of dogs undergoing enterotomy.

DESIGN

Retrospective case-control study.

ANIMALS

219 dogs that underwent splenectomy for reasons other than splenic torsion (splenectomy group; n = 172) or enterotomy (control group; 47) without concurrent gastropexy.

PROCEDURES

Medical records were reviewed for information on signalment, date of surgery, durations of surgery and anesthesia, reason for splenectomy, histopathologic findings (if applicable), whether gastropexy was performed, duration of follow-up, and date of death (if applicable). Follow-up information, including occurrence of GDV, was obtained via medical records review and a written client questionnaire.

RESULTS

Reasons for splenectomy included splenic neoplasia, nonneoplastic masses, infarction, traumatic injury, and adhesions to a gossypiboma. Incidence of GDV following surgery was not significantly different between dogs of the splenectomy (14/172 [8.1 %]) and control (3/47 [6.4%]) groups. Median time to GDV for the 17 affected dogs was 352 days (range, 12 to 2,368 days) after surgery. Among dogs that underwent splenectomy, sexually intact males had a significantly higher incidence of GDV (4/16) than did castrated males and sexually intact or spayed females (10/156). Incidence of GDV among sexually intact male dogs did not differ between groups.

CONCLUSIONS AND CLINICAL RELEVANCE

Results did not support a recommendation for routine use of prophylactic gastropexy in dogs at the time of splenectomy. Other patient-specific risk factors should be assessed prior to recommending this procedure.

A time series model of the occurrence of gastric dilatation-volvulus in a population of dogs

Background

Gastric dilatation-volvulus (GDV) is a life-threatening condition of mammals, with increased risk in large breed dogs. The study of its etiological factors is difficult due to the variety of possible living conditions. The association between meteorological events and the occurrence of GDV has been postulated but remains unclear. This study introduces the binary time series approach to the investigation of the possible meteorological risk factors for GDV. The data collected in a population of high-risk working dogs in Texas was used.

Results

Minimum and maximum daily atmospheric pressure on the day of GDV event and the maximum daily atmospheric pressure on the day before the GDV event were positively associated with the probability of GDV. All of the odds/multiplicative factors of a day being GDV day were interpreted conditionally on the past GDV occurrences. There was minimal difference between the binary and Poisson general linear models.

Conclusion

Time series modeling provided a novel method for evaluating the association between meteorological variables and GDV in a large population of dogs. Appropriate application of this method was enhanced by a common environment for the dogs and availability of meteorological data. The potential interaction between weather changes and patient risk factors for GDV deserves further investigation.

Meteorological influence on the occurrence of gastric dilatation-volvulus in military working dogs in Texas

Gastric dilatation-volvulus (GDV) is a life-threatening condition in dogs and other species in which the stomach dilates and rotates on itself. The etiology of the disease is multi-factorial, but explicit precipitating causes are unknown. This study sought to determine if there was a significant association between changes in hourly-measured temperature and/or atmospheric pressure and the occurrence of GDV in the population of high-risk working dogs in Texas. The odds of a day being a GDV day, given certain temperature and atmospheric pressure conditions for that day or the day before, was estimated using logistic regression models. There were 57 days in which GDV(s) occurred, representing 2.60% of the days in the 6-year study period. The months of November, December, and January collectively accounted for almost half (47%) of all cases. Disease risk was negatively associated with daily maximum temperature. An increased risk of GDV was weakly associated with the occurrence of large hourly drops in temperature that day and of higher minimum barometric pressure that day and the day before GDV occurrence, but extreme changes were not predictive of the disease.

Nutritional risks to large-breed dogs: from weaning to the geriatric years

Distinctive risk factors for disease are identifiable throughout life stages of large- and giant-breed dogs. From weaning to maturity, improper nutrition is linked to developmental skeletal diseases. As large dogs mature, skeletal diseases and obesity can lead to osteoarthritis. These dogs are difficult to manage when orthopedic or osteoarthritic disease affects mobility and quality of life, thereby increasing the risk of early death. Gastric dilatation and volvulus is another disease that is leading cause of death in large- and giant-breed dogs. Management of health, including proper nutrition, exercise, and weight control, provides the best opportunity for successful aging of large- and giant-breed dogs.

Risk factors associated with short-term outcome and development of perioperative complications in dogs undergoing surgery because of gastric dilatation-volvulus: 166 cases (1992–2003)

OBJECTIVE

To evaluate risk factors associated with death and development of perioperative complications in dogs undergoing surgery for treatment of gastric dilatation-volvulus (GDV).

DESIGN

Retrospective case series.

ANIMALS

166 dogs.

PROCEDURES

Records of dogs with confirmed GDV that underwent surgery were reviewed. Logistic regression was performed to identify factors associated with development of complications (ie, hypotension, arrhythmias, gastric necrosis necessitating gastrectomy, disseminated intravascular coagulation, peritonitis, sepsis, postoperative dilatation, postoperative vomiting, and incisional problems) and with short-term outcome (ie, died vs survived to the time of suture removal).

RESULTS

Short-term mortality rate was 16.2% (27/166). Risk factors significantly associated with death prior to suture removal were clinical signs for > 6 hours prior to examination, combined splenectomy and partial gastrectomy, hypotension at any time during hospitalization, peritonitis, sepsis, and disseminated intravascular coagulation. Partial gastrectomy was not a significant risk factor for death but was for peritonitis, disseminated intravascular coagulation, sepsis, and arrhythmias. Age, gastrectomy, and disseminated intravascular coagulation were risk factors for development of hypotension. Use of a synthetic colloid or hypertonic saline solution was associated with a significantly decreased risk of hypotension.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that the prognosis for dogs undergoing surgery because of GDV is good but that certain factors are associated with an increased risk that dogs will develop perioperative complications or die.

Gastric Dilatation–volvulus as Complication after Surgical Removal of a Splenic Haemangiosarcoma in a Dog

An 8-year-old crossbreed dog presented after one episode of acute collapse due to rupture of a splenic haemangiosarcoma. Following splenectomy the dog recovered well. Two days after discharge the dog re-presented because of gastric dilatation-volvulus (GDV) that eventually led to his death. Splenectomy to remove a voluminous splenic tumour may predispose to GDV and dogs may benefit from concurrent prophylactic gastropexy.

Gastric dilatation-volvulus in dogs

Gastric dilatation-volvulus (GDV) is a disease in which there is gross distension of the stomach with fluid or gas and gastric malpositioning. It causes pathology of multiple organ systems and is rapidly fatal. It is common in large- and giant-breed dogs. The disease appears to have a familial predisposition. Thoracic depth/width ratio also appears to predispose dogs to GDV. Implicated dietary factors include dietary particle size, frequency of feeding, speed of eating, aerophagia and an elevated feed bowl. A fearful temperament and stressful events may also predispose dogs to GDV. Abdominal distension, non-productive retching, restlessness, signs of shock, tachypnoea and dyspnoea are possible clinical signs. Initial treatment includes treatment of shock and gastric decompression. Surgical treatment should be performed promptly. There are no studies comparing the use of different anaesthetic agents in the anaesthetic management of GDV. Pre-medication with an opioid/benzodiazepine combination has been recommended. Induction agents that cause minimal cardiovascular changes such as opioids, neuroactive steroidal agents and etomidate are recommended. Anaesthesia should be maintained with an inhalational agent. Surgical therapy involves decompression, correction of gastric malpositioning, debridement of necrotic tissue, and gastropexy. Options for gastropexy include incisional, tube, circumcostal, belt-loop, incorporating, and laparoscopic gastropexy. Expected mortality with surgical therapy is 15-24%. Prognostic factors include mental status on presentation, presence of gastric necrosis, presence of cardiac arrhythmia and plasma lactate levels. Prophylactic gastropexy should be considered in dogs identified as being at high risk.

Prospective evaluation of laparoscopic-assisted gastropexy in dogs susceptible to gastric dilatation

OBJECTIVE

To determine long-term outcome associated with laparoscopic-assisted gastropexy in prevention of gastric dilatation-volvulus (GDV) in susceptible dogs and to evaluate use of laparoscopy to correct GDV.

DESIGN

Prospective study.

ANIMALS

25 client-owned large-breed dogs.

PROCEDURE

23 dogs susceptible to GDV were referred as candidates for elective gastropexy. These dogs had a history of treatment for gastric dilatation, clinical signs of gastric dilatation, or family members with gastric dilatation. Laparoscopic-assisted gastropexy was performed. One year after surgery, abdominal ultrasonography was performed to evaluate the attachment of the stomach to the abdominal wall. Two dogs with GDV were also treated with laparoscopic-assisted derotation of the stomach and gastropexy.

RESULTS

None of the dogs developed GDV during the year after gastropexy, and all 20 dogs examined ultrasonographically had an intact attachment. Another dog was euthanatized at 11.5 months for unrelated problems. Two dogs with GDV successfully underwent laparoscopic-assisted gastropexy after the stomach was repositioned.

CONCLUSIONS AND CLINICAL RELEVANCE

Laparoscopic-assisted gastropexy resulted in a persisting attachment between the stomach and abdominal wall, an absence of GDV development, and few complications. Dogs with a high probability for development of GDV should be considered candidates for minimally invasive gastropexy. Carefully selected dogs with GDV can be treated laparoscopically.