Factors contributing to the decision for euthanasia of dogs with congestive heart failure

OBJECTIVE

To determine the prevalence of clinical signs that affect quality of life in dogs with congestive heart failure (CHF), and to characterize the role of these clinical signs in the decision for euthanasia.

DESIGN

Prospective study.

ANIMALS

38 dogs with CHF that had been euthanatized within the preceding 22 months.

PROCEDURE

Clinical information and factors affecting the decision for euthanasia were reviewed and recorded from medical records of dogs with CHF. Each owner was then interviewed via telephone to determine whether their dog had anorexia or other clinical signs of disease prior to euthanasia, their perception of their dogs' quality of life, and the most important factor and contributing factors that influenced the decision to euthanatize their dog.

RESULTS

Of the 38 dogs with CHF, > 70% had weakness (35 dogs), coughing (33), anorexia (32), weight loss (32), dyspnea (30), or exercise intolerance (28) reported by their owners. Factors often named by owners as most important in the decision for euthanasia were poor prognosis given by the attending veterinarian, recurrent clinical signs of CHF (ie, coughing, dyspnea, or ascites), and poor quality of life. Weakness, anorexia, and recurrent clinical signs of CHF were the most common contributing factors in the decision for euthanasia.

CLINICAL IMPLICATIONS

Anorexia, weight loss, and exercise intolerance are common in dogs euthanatized because of CHF. The importance of quality of life and poor prognosis in making a decision for euthanasia suggests that addressing these factors may improve patient management.

Amphibian pain and analgesia

Analgesics are often not provided to amphibians because the presence and severity of pain may not be recognized in these animals. In addition, there is little information on the mechanism of action of analgesic agents in amphibians. However, amphibians possess appropriate neurologic components for transmitting pain from peripheral receptors to the central nervous system and antinociceptive mechanisms to modulate pain. They are capable of displaying behavioral and physiologic modification of pain systems in response to analgesic pharmacologic agents. Therefore, pain perception in amphibians is likely analogous to that in mammals and invasive, potentially painful procedures should be accompanied by appropriate analgesia and anesthesia. Although specific doses have not been established in clinical trials, basic research into the mechanisms and regulation of endogenous opioid systems demonstrates the potential clinical benefit for the use of opioids in these animals. Other analgesics such as alpha2-agonists, ketamine, and tricaine methanesulfonate have also demonstrated analgesic potential.

Cecocolic and cecocecal intussusception in horses: 30 cases (1976-1996)

OBJECTIVE

To determine the prognosis in horses with cecocolic or cecocecal intussusception.

DESIGN

Retrospective study.

ANIMALS

30 horses with cecocolic intussusception or cecocecal intussusception.

PROCEDURE

Information on history, physical examination findings, and laboratory values was summarized from the medical records. Laboratory data included results of hematologic examination, serum biochemical analysis, and peritoneal fluid color, total nucleated cell count, and total protein concentration. A one-year follow-up via the telephone was used to determine long-term survival.

RESULTS

Horses ranged from 7 months to 30 years old, but 63% were < or = 3 years. Standardbred horses were significantly overrepresented. Twenty-six horses had acute-to-subacute disease, and 4 had a chronic wasting disease. Cecal intussusceptions were suspected on the basis of finding a mass on abdominal palpation per rectum (14 of 24 horses) and positive ultrasonographic findings (2 of 3 horses). Thirteen horses with colic for > 1 day had scant, soft feces. Six horses died or were euthanatized without undergoing surgery, and 24 were treated surgically. Six of the latter horses were euthanatized during surgery because of peritonitis, rupture of the cecum, and irreducible intussusception. All 4 horses with a chronic disease were euthanatized because of irreversible changes in the cecum. Of the 18 horses allowed to recover from surgery, 15 survived long-term. Surgical treatments were reduction, with or without partial typhlectomy (6 horses), partial typhlectomy through a colotomy and reduction (6), reduction through a colotomy and partial typhlectomy (3), partial typhlectomy for a cecocecal intussusception (1) and an ileocolostomy (2).

CLINICAL IMPLICATIONS

Cecal intussusception has a good prognosis with surgical correction without delay. Reduction through colotomy has a high success rate. Bypass by ileocolostomy should be used as a last resort.

Field immobilization and euthanasia of American opossum

Seventeen recently trapped opossum, Didelphis virginiana, (median weight 2.45 kg; range = 1.6-5.0 kg; quartiles = 1.8-3.3 kg) were immobilized with either telazol (15 or 30 mg/kg) or a mixture of medetomidine (100 micrograms/kg), butorphanol (0.2 mg/kg), and ketamine HCl (10 mg/kg) based on estimated weights. Anesthetized animals were subjected to cardiac puncture for blood withdrawal and toe pinch. Euthanasia was accomplished by intracardiac administration of 1 ml of concentrated pentobarbital sodium/phenytoin solution. Weights were underestimated for 14 of 17 animals, but were within 0.5 kg of the actual weight. Both drug combinations provided rapid and calm immobilization. Median time to recumbency for the medetomidine-butorphanol-ketamine group (n = 5) was 6 min (range = 4-10 min; quartiles = 6 and 8 min). The median time to recumbency was not statistically different for the low (n = 6) and high dose (n = 6) telazol groups, 3 and 3.5 min respectively (quartiles 3; 3.5 and 4; 5.5 min). The stronger heart beat with telazol immobilization facilitated cardiac puncture. All five animals administered the medetomidine-butorphanol-ketamine mixture and three of six animals given the low telazol dose reacted to cardiac puncture. Only one of six animals given the estimated 30 mg/kg dose of telazol reacted slightly to cardiac puncture. We conclude that 30 mg/kg telazol provides sufficient immobilization and analgesia to allow accurate cardiac puncture of the opossum if the procedure is performed within 5 to 10 min of recumbency. Intracardiac administration of concentrated pentobarbital sodium/phenytoin solution followed by bilateral thoracotomy provides appropriate euthanasia suitable for field situations.

Generalised amyloidosis in two Siamese cats: spontaneous liver haemorrhage and chronic renal failure

Two cases are reported, illustrating the antemortem diagnosis of systemic amyloidosis in Siamese cats. A cat presenting with inappetence and depression was diagnosed as having systemic amyloidosis with spontaneous haemorrhage from the liver. In another cat from the same breeding cattery, chronic renal failure due to systemic amyloidosis was an incidental finding. Little treatment was possible in either case and both were later euthanased. The two cats had similar renal and hepatic pathology but different signs of disease.

Unilateral cerebral necrosis resembling feline ischemic encephalopathy in an African lion (Panthera leo)

In November 1996, a 14-yr-old captive male African lion (Panthera leo) had sudden onset of left-sided hemiparesis and mydriasis of the left eye. After 24 hr of supportive care, the lion showed no improvement and was euthanized. At necropsy, the right cerebral hemisphere was diffusely and irregularly swollen and malacic. Histopathology revealed extensive acute necrosis and edema of the portion of the right cerebral hemisphere that received blood from the right middle cerebral artery. Gross and histopathologic cerebral findings resembled those of feline ischemic encephalopathy.

Demographic and needs assessment survey of animal care and control agencies

OBJECTIVE

To characterize demographic and needs assessment information for animal care and control agencies in Ohio.

DESIGN

Mail survey.

SAMPLE POPULATION

222 animal care and control agencies.

PROCEDURE

A questionnaire was mailed to animal care and control agencies in Ohio. Data were collected for 1996.

RESULTS

Of 222 agencies contacted, 180 (81%) responded. Agencies estimated that they spent $28.4 million ($2.47/person). Approximately 339,207 animals were taken in, comprising 214,143 (63%) dogs, 114,877 (34%) cats, and 10,187 (3%) wildlife or other species. Of these animals, a fourth were adopted, about a tenth were reclaimed by their owners, and two thirds were euthanatized. Approximately 302,589 animal control complaints were received, and 22,053 (7%) citations were issued. One hundred three (57%) agencies reported 25,564 cruelty complaints; criminal charges were filed for 543 (2%) cases, with 445 (82%) resulting in guilty verdicts. Among 155 agencies that provided information, 87 (56%) had spay/neuter policies. Only 69 of 178 (39%) agencies reported an association with a veterinarian. Less than half (64/150; 43%) of the agencies administered vaccinations, and 69 of 152 (45%) treated animals for intestinal parasites. The top 5 things needed by agencies were capital/facility improvements, increased funding, improved legislation for animals, educational needs, and veterinary services.

CLINICAL IMPLICATIONS

In Ohio in 1996, 9.9% of dogs and 4.5% of cats received care or assistance from animal care and control agencies. Only 39% of animal care and control agencies have an association with a veterinarian.

Canine mesenchymal chondrosarcoma of the ribs

The tumor of the thoracic cavity, which arose from the ribs, was diagnosed as mesenchymal chondrosarcoma. No distant metastasis was observed. Histologically, the tumor was characterized by the nests of well-defined cartilaginous tissue within a proliferation of primitive mesenchymal cells. Additionally, the deformed blood vessels compressed by the proliferating mesenchymal cells exhibited clear stag-horn appearance. Immunohistochemically, most neoplastic cells that formed multifocal cartilaginous islands were positive for S-100 protein, while the surrounding mesenchymal cells were negative. This is the first report of canine mesenchymal chondrosarcoma of the ribs.

Program for surveillance of causes of death of dogs, using the Internet to survey small animal veterinarians

OBJECTIVE

To develop a prototype program for surveillance of causes of death of dogs, using resources developed for the World Wide Web, to enable collection of data from veterinarians in small animal practice and dissemination of results in a timely manner at minimal expense.

DESIGN

Epidemiologic survey.

SAMPLE POPULATION

Small animal veterinarians who were members of NOAH, Veterinary Information Network (VIN), or VetPlus-L.

PROCEDURE

Internet electronic communications and Web pages were used for solicitation and collection of data, dissemination of results, and follow-up discussions with participants. Data were stored in a relational database.

RESULTS

25 veterinarians actively submitted case material. On the basis of analysis by region and school of veterinary medicine attended, these veterinarians were representative of all small animal practitioners in the United States. During the 6-month study, 621 case reports were submitted. Analysis of results included determination of number of dogs, with proportions calculated for primary reason for death, primary clinical sign, and breed, as well as creation of a map depicting distribution of the practitioners. Additional data were obtained for analysis to provide information of interest.

CLINICAL IMPLICATIONS

A national database representative of dogs examined by small animal practitioners would be a valuable source of information. Rapidly and easily accessible return of information and results is important for any surveillance system. The program described here appears to be a successful method for collecting data from practitioners.

Comparison of five regimens for oral administration of medication to induce sedation in dogs prior to euthanasia

OBJECTIVE

To compare regimens for oral administration of medication to induce sedation in dogs prior to euthanasia.

DESIGN

Prospective randomized clinical study.

ANIMALS

37 dogs.

PROCEDURE

Groups and medications were as follows: group 1, acepromazine (n = 8); group 2, tiletamine-zolazepam (8); group 3, tiletamine-zolazepam and acepromazine (8); group 4, tiletamine-zolazepam and butorphanol (6); and group 5, pentobarbital sodium (7). Capsules or tablets were placed in each dog's food. Sedation was scored at 3-minute intervals after consumption of medication for at least 60 minutes. Dogs with signs of persistent or progressive sedation were observed for 90 minutes.

RESULTS

Only 2 dogs in group 1 became slightly ataxic. All group-2 dogs were slightly ataxic, and 4 of 8 became laterally recumbent (mean time to lateral recumbency, 62 minutes). Seven of 8 group-3 dogs became sternally recumbent, and 6 of these dogs became laterally recumbent (mean, 48.6 minutes). Four of 6 group-4 dogs were slightly or moderately ataxic, and 1 of these dogs became laterally recumbent (mean, 48 minutes). One dog in group 5 was not affected by the medication, but all other group-5 dogs became laterally recumbent (mean, 59 minutes).

CLINICAL IMPLICATIONS

Of the medications evaluated, tiletamine-zolazepam and acepromazine at dosages of approximately 20 mg/kg (9.1 mg/lb) and 2 mg/kg (0.91 mg/lb), respectively, or pentobarbital sodium alone (63.2 +/- 5.1 mg/kg [28.7 +/- 2.3 mg/lb]) most consistently induced profound sedation and lateral recumbency after oral administration to dogs.

Comparison of four regimens for intraoral administration of medication to induce sedation in cats prior to euthanasia

OBJECTIVE

To compare 4 regimens for intraoral administration of medication to induce sedation in cats prior to euthanasia.

DESIGN

Prospective randomized clinical study.

ANIMALS

36 cats.

PROCEDURE

Cats were assigned to 4 groups (9 cats/group). Cats in each group were given the following medications: group 1, detomidine (0.5 mg/kg [0.23 mg/lb] of body weight); group 2, ketamine hydrochloride (5 mg/kg [2.3 mg/lb]); group 3, detomidine (0.5 mg/kg) and ketamine (5 mg/kg); and group 4, detomidine (0.5 mg/kg) and ketamine (10 mg/kg [4.5 mg/lb]). All medications were administered by squirting the drug or drug combination into the mouth of a cat, using a syringe or, for intractable cats, a remote delivery device. Cats were evaluated for degree of sedation at 3-minute intervals for 60 minutes.

RESULTS

Of the 9 cats in group 1, 7 assumed lateral recumbency. Mean (+/- SD) interval from administration of medication to lateral recumbency was 15 +/- 3 minutes. For group-2 cats, 1 cat achieved sternal recumbency (sternally recumbent and unable to stand), whereas the remaining 8 cats achieved mild to moderate degrees of sedation. For group 3, 6 of 9 cats assumed lateral recumbency (mean, 16.5 +/- 3.7 minutes). For group 4, all 9 cats assumed lateral recumbency (mean, 17 +/- 8 minutes).

CLINICAL IMPLICATIONS

Analysis of results of this study indicated that a combination of detomidine (0.5 mg/kg) and ketamine (10 mg/kg) administered intraorally provide an effective and reliable method for sedating cats.

Peripheral neuroblastoma and primitive neuroectodermal tumor in Japanese black cattle

Peripheral neuroblastoma was found in a 1-year-old, male, Japanese black cattle (Case 1) and primitive neuroectodermal tumor was noted in 7-year-old, female, Japanese black cattle (Case 2). In Case 1, neoplastic tissue was replaced the right cranial vault and nasopharynx. A large, soft mass approximately 18 cm in diameter was also observed in the right mandibulopharyngeal area. In Case 2, a neoplastic mass of about 15 cm in diameter was found in the mandibulopharyngeal area. Histopathologically, massive necrosis showing a pseudopalisade arrangement was frequently observed in Case 1. On the contrary, Homer & Wright rosette formations of tumor cells were prominent in Case 2. Immunohistochemically, the proliferating cells in Case 1 were positive for vimentin, S-100, and neurofilament (NF) and those in Case 2 showed intense immunoreactivity for NF and neuron specific enolase, but were negative for vimentin and S-100. The different degrees of differentiation of the neoplastic cells originating from the neuroectoderm, might be reflected in their different morphological and immunohistochemical features.

[Cancer eye in cattle: 21 cases (1990-1996)]

Between 1990 and 1996, 21 cows suffering from cancer eye had been admitted to the Clinic for Food Animals and Horses, University of Bern. Case history and localization and dimension of the tumor at admission were evaluated. Treatment consisted of bulbus extirpation in 17 of 21 cows. In two cows, cryosurgery was performed, while two cows were slaughtered for economic reasons. Telephone follow-up inquiries were performed between 10 and 84 months after surgery. Mean survival time after surgery was 15 months. Recurrence of the tumor was evident in six cases within 2 to 14 months after surgery. We recommend bulbus extirpation in cows with cancer eye to extend productive life.

[Therapy or euthanasia? How far may (and should) the veterinarian go in the treatment of an animal?]

Veterinarians are often faced with the question of whether they should treat or--in accordance with the animal owner--to end the life of a pet animal. This situation can be described as a moral dilemma. Can this moral dilemma be solved? The author argues that we have special moral obligations to care for pet animals. The special, quasi-personal relationships between pet animal and animal owners provide veterinarians in most cases with moral reasons to carry out the treatment.

Right-sided heart failure in a dog with primary cardiac rhabdomyosarcoma

A seven-year-old, female German shepherd mixed-breed dog was presented with weakness, inappetence, and a distended abdomen. Right-sided heart failure with pleural, pericardial, and abdominal effusions; dyspnea; and tachycardia were identified. The radiographic and electrocardiographic examinations did not allow a conclusive diagnosis. Echocardiographic findings included a mass in the wall of both the right atrium and right ventricle, partially occupying the right heart cavities. A diagnosis of cardiac tumor was made, and the owner elected euthanasia. The necropsy confirmed a tumor mass located in the right atrium and right ventricle. A definitive diagnosis of primary cardiac rhabdomyosarcoma was based on histopathological and immunohistochemical analyses.

Congenital interruption of the portal vein and caudal vena cava in dogs: six case reports and a review of the literature

OBJECTIVE

To describe six dogs with congenital abnormalities involving the portal vein, caudal vena cava, or both.

ANIMALS

Six client-owned dogs with congenital interruption of the portal vein or the caudal vena cava, or both.

METHODS

Portal vein and caudal vena cava anatomy was evaluated by contrast radiography and visualization at surgery. Vascular casts or plastinated specimens were obtained in three animals.

RESULTS

Portal blood shunted into the caudal vena cava in four dogs and the left hepatic vein in one. Two of these five dogs also had interruption of the caudal vena cava with continuation as azygous vein, as did an additional dog, in which the portal vein was normally formed. Portal vein interruption was present in 5 of 74 (6.8%) dogs with congenital portosystemic shunts evaluated at the Veterinary Teaching Hospital during the study period.

CONCLUSIONS

Serious malformations of the abdominal veins were present in more than 1 in 20 dogs with single congenital portosystemic shunts.

CLINICAL RELEVANCE

Veterinarians involved in diagnosis and surgery for portosystemic shunts should be aware of these potential malformations, and portal vein continuity should be evaluated in all dogs before attempting shunt attenuation.

Diabetes mellitus in a koala (Phascolarctos cinereus)

OBJECTIVE

To describe a case of diabetes mellitus in a koala (Phascolarctos cinereus).

DESIGN

A case report with controls.

PROCEDURES

We describe clinical and laboratory findings in a 6-year-old, free-living, female koala presented with traumatic injury and subsequently found to have polydipsia, hyperglycaemia and glucosuria. Over a 5 week period, serum biochemical analyses, haematological examinations, urinalyses, measurement of serum insulin and fructosamine concentrations, necropsy, histopathological examination of a range of tissues and immunohistochemical examination of the pancreas for insulin-containing cells were done. For reference purposes, serum insulin and fructosamine concentrations were determined in four and two healthy koalas, respectively, and three healthy koalas' pancreases were examined histologically and immunohistochemically.

RESULTS

The koala had persistent hyperglycaemia, hyperlipidaemia, hyponatraemia, hypochloraemia and glucosuria. Serum insulin concentration of the diabetic koala was only marginally smaller than that of healthy koalas, but all concentrations were smaller than reference concentrations in dogs and people. Fructosamine concentration did not allow the diabetic koala to be distinguished from healthy koalas and concentrations of all koala analytes were greater than expected for healthy dogs and people. Histopathological examination revealed extensive degeneration of pancreatic islet cells and fatty infiltration of hepatocytes. Immunoperoxidase staining revealed decreased or absent insulin in the beta calls of the affected koala.

CONCLUSION

Clinical signs, clinicopathological results and histopathological changes were consistent with diabetes mellitus. The pathogenesis of the condition could not be determined but may have been related to the administration of a parenteral corticosteroid preparation, the stress of capture or tissue damage and inflammation.