Emesis in dogs: a review

Antiemetic activity of abietic acid possibly through the 5HT3 and muscarinic receptors interaction pathways

The present study was designed to evaluate the antiemetic activity of abietic acid (AA) using in vivo and in silico studies. To assess the effect, doses of 50 mg/kg b.w. copper sulfate (CuSO4⋅5H2O) were given orally to 2-day-old chicks. The test compound (AA) was given orally at two doses of 20 and 40 mg/kg b.w. On the other hand, aprepitant (16 mg/kg), domperidone (6 mg/kg), diphenhydramine (10 mg/kg), hyoscine (21 mg/kg), and ondansetron (5 mg/kg) were administered orally as positive controls (PCs). The vehicle was used as a control group. Combination therapies with the referral drugs were also given to three separate groups of animals to see the synergistic and antagonizing activity of the test compound. Molecular docking and visualization of ligand-receptor interaction were performed using different computational tools against various emesis-inducing receptors (D2, D3, 5HT3, H1, and M1-M5). Furthermore, the pharmacokinetics and toxicity properties of the selected ligands were predicted by using the SwissADME and Protox-II online servers. Findings indicated that AA dose-dependently enhances the latency of emetic retching and reduces the number of retching compared to the vehicle group. Among the different treatments, animals treated with AA (40 mg/kg) exhibited the highest latency (98 ± 2.44 s) and reduced the number of retching (11.66 ± 2.52 times) compared to the control groups. Additionally, the molecular docking study indicated that AA exhibits the highest binding affinity (- 10.2 kcal/mol) toward the M4 receptors and an elevated binding affinity toward the receptors 5HT3 (- 8.1 kcal/mol), M1 (- 7.7 kcal/mol), M2 (- 8.7 kcal/mol), and H1 (- 8.5 kcal/mol) than the referral ligands. Taken together, our study suggests that AA has potent antiemetic effects by interacting with the 5TH3 and muscarinic receptor interaction pathways. However, additional extensive pre-clinical and clinical studies are required to evaluate the efficacy and toxicity of AA.

An experimental study of consecutive administration of ropinirole and apomorphine for emesis induction in dogs

OBJECTIVE

To study the safety and effectiveness of consecutively administered ropinirole and apomorphine (both dopamine 2-like receptor agonists) for emesis induction in dogs.

DESIGN

Prospective, crossover study design.

SETTING

Institutional animal research facility.

ANIMALS

Six healthy male purpose-bred Beagle dogs.

INTERVENTIONS

Each dog received 4 treatments: (1) apomorphine infusion (21 μg/kg) over 30 minutes + ropinirole eye drops (3.75 mg/m2 ); (2) ropinirole infusion (108 μg/m2 ) over 30 minutes + apomorphine SC (100 μg/kg); (3) apomorphine SC (100 μg/kg) + ropinirole eye drops (7.5 mg/m2 ) after 30 minutes; and (4) ropinirole eye drops (7.5 mg/m2 ) + apomorphine SC (100 μg/kg) after 30 minutes. Infusions were administered via a catheter instrumented in the cephalic vein. Eye drops and SC injections were administered as described in the product inserts. Blood samples were taken for ropinirole and apomorphine concentration analysis before dosing and periodically following administrations. The washout period between the treatments was 5-7 days.

MEASUREMENTS AND MAIN RESULTS

Number of vomits and clinical signs were recorded. Alertness and heart rate were monitored in conjunction with blood sampling. The average number of vomits varied between 4.3 and 8.8 (range 1-16) following treatments. Signs of nausea, vomiting, and lethargy were seen in all individuals without significant differences between treatments. Moderate to marked, transient increase in heart rates was detected in all treatments. Infrequent noted side effects included ocular hyperemia, blepharospasms, and muscle tremors. Prior treatment with apomorphine significantly decreased the absorption of ropinirole eye drops.

CONCLUSIONS

The safety and efficacy profiles of this experimental study support that ropinirole and apomorphine could be administered consecutively in cases where the treatment using 1 substance has resulted in an incomplete evacuation of the stomach contents, and the attending veterinarian considers the use of a different agent to have benefits that outweigh the risks.

Retrospective Evaluation of Gastrointestinal Signs in Hypothyroid Dogs

Few observations about gastrointestinal (GI) signs in hypothyroid dogs (hypo-T dogs) are available. We aimed to evaluate the prevalence and characteristics of concurrent GI signs in hypo-T dogs, describe clinicopathological, hepato-intestinal ultrasound findings in hypo-T dogs, investigate changes in GI signs after thyroid replacement therapy (THRT). Medical records of suspected hypo-T dogs from two hospitals were retrospectively reviewed. The inclusion criteria were: (1) having symptoms and clinicopathological abnormalities related to hypothyroidism (i.e., mild anemia, hyperlipemia); (2) not being affected by systemic acute disease; (3) not having received any treatment affecting thyroid axis. Hypothyroidism had to be confirmed using low fT4 or TT4 with high TSH and/or inadequate TSH-stimulation test response; otherwise, dogs were assigned to a euthyroid group. Clinical history, GI signs, hematobiochemical parameters, and abdominal ultrasound findings were recorded. Hypo-T dogs were assigned to the GI group (at least 2 GI signs) and not-GI group (1 or no GI signs). Follow-up information 3-5 weeks after THRT was recorded. In total, 110 medical records were screened: 31 dogs were hypo-T, and 79 were euthyroid. Hypo-T dogs showed a higher prevalence of GI signs (44%), especially constipation and diarrhea (p = 0.03 and p = 0.001), than euthyroid dogs (24%) (p = 0.04). Among hypo-T dogs, no difference in hematological parameters between GI and non-GI groups was found. Hypo-T dogs had a higher prevalence of gallbladder alterations than euthyroid dogs (20/25; 80% and 32/61; 52% p = 0.04). The hypo-T GI group showed a significant improvement in the GI signs after THRT (p < 0.0001). Specific investigation for concurrent GI diseases in hypo-T dogs was lacking; however, improvement in GI signs following THRT supports this association between GI signs and hypothyroidism.

Toxicokinetics in preclinical drug development of small-molecule new chemical entities

Toxicokinetics (TK) is an integral part of nonclinical (preclinical) safety assessment of small-molecule new chemical entities in drug development. It is employed to describe the systemic exposure of a drug candidate and/or its important metabolite(s) achieved in study animals and elucidate the relationship (proportional, over-proportional, or under-proportional) between systemic exposure and dose administered and the associated differences/similarities between male and female animals along with the possible accumulation/induction. TK data and the derived parameters are employed to propose safe starting doses for clinical use of the new drug candidate through proper extrapolation of findings in study animals to humans. This review has attempted to highlight the health authority expectations on TK assessment in supporting preclinical safety profiling of new chemical entities. A robust TK assessment requires good understanding of absorption, distribution, metabolism, and elimination processes of drug candidate, adequate TK sampling (e.g., controls where relevant), implementation of fit-for-purpose bioanalytical methods (validated or scientifically qualified) along with necessary measures to prevent mis-dosing or ex vivo contamination, and establishment of stability of the drug candidate and/or its metabolite(s) in the intended species matrix to ensure the reliability of bioanalytical and TK data. The latter provides a vital link between animal experiments and human safety.

Life-threatening gastrointestinal bleeding caused by jejunal heterotopic gastric mucosa in an adult dog: a rare case report

Background

Heterotopic gastric mucosa has been scarcely reported in the veterinary literature. Its presence can be asymptomatic or associated with various clinical signs ranging from apathy, vomiting, to abdominal pain. This report illustrates the presence of heterotopic gastric mucosa in the jejunum of an adult dog. It is the first to describe severe anemia, requiring acute blood transfusion, following intestinal hemorrhage caused by heterotopic gastric mucosa.

Case presentation

A twelve-year-old, intact male Maltese dog was presented with a history of apathy, vomiting and anemia. The dog was on a strict diet for recurrent diarrhea, food intolerance and skin allergy. Clinical examination revealed severe anemic mucous membranes and painful abdominal palpation. Blood examination confirmed severe regenerative anemia. Ultrasonography showed an intestinal neoplasm, gall bladder sludge and non-homogeneous liver parenchyma. Three-view thoracic radiographs failed to show any metastatic lesions or enlarged lymph nodes. After initial stabilization and blood transfusion, a midline exploratory laparotomy was performed. Three different masses were found in the jejunum. Resection and anastomosis of approximately 40 cm of jejunum was performed, followed by liver and lymph node biopsy and placement of an esophagostomy tube. Two days after surgery the dog started to clinically improve and was discharged from the hospital on the sixth day after surgery. Histopathology revealed the intestinal masses to be heterotopic gastric mucosa associated with intramural cystic distensions, multifocal ulceration and bleeding into the intestinal lumen. Two years after surgery, the dog did not have a recurrence of anemia or gastrointestinal signs.

Conclusions

This case demonstrates that heterotopic gastric mucosa can be considered one of the differential diagnoses in case of severe anemia due to gastrointestinal hemorrhage and suspected intestinal tumors. Although in most described cases in literature the finding seems to be incidental on necropsy, our report shows that heterotopic gastric mucosa can be the etiology of life-threatening signs. In addition, because no recurrent diarrhea episodes occurred after surgical resection of the ectopic tissue, it is likely that the heterotopic gastric mucosa was the cause of the food intolerance signs in this dog.

Treatment of Canine Oral Melanomas: A Critical Review of the Literature

Critical appraisal of the available literature for the treatment of canine oral malignant melanoma (OMM) is lacking. This critical review aimed to evaluate the current literature and provide treatment recommendations and possible suggestions for future canine OMM research. PubMed, Web of Science and Google Scholar were searched in June 2021, for terms relevant to treatment of OMM. Inclusion and exclusion criteria were applied and information on clinical response and outcome extracted. Eighty-one studies were included. The overall level of evidence supporting the various canine OMM treatment options was low. The majority of studies included confounding treatment modalities and lacked randomization, control groups and consistency in reporting clinical response and outcomes. Within these limitations, surgery remains the mainstay of therapy. Adjunctive radiotherapy provided good local control and improved median survival times (MST), chemotherapy did not offer survival benefit beyond that of surgery, while electrochemotherapy may offer a potential alternative to radiotherapy. Immunotherapy holds the most promise in extending MST in the surgical adjunctive setting, in particular the combination of gene therapy and autologous vaccination. Prospective, randomized, double-blinded clinical trials, with a lack of confounding factors and reporting based on established guidelines would allow comparison and recommendations for the treatment of canine OMM.

Clinical Applications of Substance P (Neurokinin-1 Receptor) Antagonist in Canine Medicine

Substance P binds to the Neurokinin-1 (NK-1) receptors found in the emetic center of the central nervous system (CNS) to induce emesis. Maropitant is a selective NK-1 receptor antagonist that inhibits the binding of substance P to NK-1 receptors and is commonly used to prevent and treat vomiting in dogs. This review study aimed to discuss and analyze the therapeutic potential of substance P (Neurokinin-1 receptor) antagonist with a particular focus on the drug maropitant in canine medicine. A systematic literature review was performed to identify the existing literature on the subject during the past 20 years (2001-2021) using such databases as ScienceDirect, PubMed, Scopus, and Google Scholar. The initial search identified 173 articles; however, 41 articles were selected for further analysis, based on the specific inclusion and exclusion criteria. Studies have already confirmed the role of substance P and NK-1 receptors in central pain processing, intestinal smooth muscle contraction, vasodilation, and neurogenic inflammation. Maropitant is one of the most effective veterinary antiemetic drugs that work well against peripheral and central stimuli that trigger the vomiting center. It has been already demonstrated that the therapeutic efficacy of maropitant for managing acute vomiting in dogs is associated with pancreatitis, gastritis, and parvoviral enteritis. It can also prevent and treat chemotherapy-induced emesis and delay the signs of nausea and adverse gastrointestinal effects. Regarding the broad-spectrum antiemetic activity of maropitant, it can be recommended for managing uremic vomiting in dogs. In addition, it has also exhibited an anesthetic sparing effect since the dogs treated with maropitant require a slightly lower percentage of isoflurane as an inhalational anesthetic. The NK-1 receptors are also identified in different areas of the pain pathways. Therefore, NK-1 receptor antagonists might be effective for managing visceral pain. However, further studies are required to establish the broad therapeutic potential of NK-1 receptor antagonist drugs, such as maropitant in canine medicine. It has been shown that the pain associated with the subcutaneous administration of maropitant is due to metacresol, a preservative used in some formulations. Therefore, the side effects can be eliminated by developing novel maropitant formulations specifically for dogs.

Induction of emesis with apomorphine using a novel gingival administration method in dogs

OBJECTIVE

To describe a novel method of inducing emesis in the dog using gingival administration of apomorphine, compare the efficacy of inducing emesis with gingival apomorphine to conjunctival apomorphine, and describe adverse effects associated with the gingival route.

DESIGN

Retrospective study from January 2017 to September 2018.

SETTING

Independent all-hours primary and secondary emergency and critical care referral center.

ANIMALS

Five hundred fifty-eight client-owned dogs.

MEASUREMENTS AND MAIN RESULTS

The medical records of dogs presenting for induction of emesis were searched. Dogs receiving either gingival or conjunctival apomorphine were included in the study. A short online survey was sent to clients whose dogs received gingival apomorphine. Apomorphine was administered conjunctivally in 430 (77.1%) dogs and gingivally in 128 (22.9%) dogs. There was no difference between route of administration and success of emesis (p = 0.29). A total of 14 clients responded to the survey, and diarrhea, lethargy, hyperactivity, and sedation were reported as adverse effects of gingival apomorphine administration. No clients sought veterinary attention for any of the adverse effects reported.

CONCLUSIONS

Gingival administration of apomorphine is easy, appears to be safe, and is an effective method of inducing emesis in the dog. Gingival administration of apomorphine may be considered in cases where parenteral administration is not feasible and could replace conjunctival administration in compliant dogs.

The use of ondansetron for the treatment of nausea in dogs with vestibular syndrome

Background

Vestibular syndrome is often accompanied by nausea. Drugs currently approved for its treatment have been developed to stop vomiting but not nausea. The efficacy of 5-HT₃ receptor antagonists to reduce nausea has been described for chemotherapy, but not for nausea secondary to vestibular disorders.

Methods

Sixteen dogs with vestibular syndrome-associated nausea were included in the open-label, multicentre study. The intensity of nausea-like behaviour was analysed before ondansetron administration (0.5 mg/kg i.v.) and 2 h afterwards, using a validated 5-point-scale. The occurrence and frequency of salivation, lip licking, restlessness, vocalisation, lethargy, and vomiting were assessed.

Results

All dogs initially showed signs of nausea, whereas only 31% showed vomitus. The intensity of nausea was significantly reduced in all dogs (p ≤ 0.0001) 2 h after ondansetron administration, including the clinical signs of nausea analysed in 11 dogs (salivation [p = 0.0078], lip licking [p = 0.0078], restlessness [p = 0.0039], and lethargy [p = 0.0078]) except for vocalisation (p > 0.9999).

Conclusions

The results provide preliminary evidence of the potential benefit of ondansetron in the treatment of nausea, which was present in all examined dogs. Vomiting was only observed in 5 dogs indicating that nausea can occur separately and should not be perceived only as a preceding stimulation of the vomiting centre.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02931-9.

Outbreak of Severe Vomiting in Dogs Associated with a Canine Enteric Coronavirus, United Kingdom

The lack of population health surveillance for companion animal populations leaves them vulnerable to the effects of novel diseases without means of early detection. We present evidence on the effectiveness of a system that enabled early detection and rapid response a canine gastroenteritis outbreak in the United Kingdom. In January 2020, prolific vomiting among dogs was sporadically reported in the United Kingdom. Electronic health records from a nationwide sentinel network of veterinary practices confirmed a significant increase in dogs with signs of gastroenteric disease. Male dogs and dogs living with other vomiting dogs were more likely to be affected. Diet and vaccination status were not associated with the disease; however, a canine enteric coronavirus was significantly associated with illness. The system we describe potentially fills a gap in surveillance in neglected populations and could provide a blueprint for other countries.

Dopamine receptors in emesis: Molecular mechanisms and potential therapeutic function

Dopamine is a member of the catecholamine family and is associated with multiple physiological functions. Together with its five receptor subtypes, dopamine is closely linked to neurological disorders such as schizophrenia, Parkinson's disease, depression, attention deficit-hyperactivity, and restless leg syndrome. Unfortunately, several dopamine receptor-based agonists used to treat some of these diseases cause nausea and vomiting as impending side-effects. The high degree of cross interactions of dopamine receptor ligands with many other targets including G-protein coupled receptors, transporters, enzymes, and ion-channels, add to the complexity of discovering new targets for the treatment of nausea and vomiting. Using activation status of signaling cascades as mechanism-based biomarkers to foresee drug sensitivity combined with the development of dopamine receptor-based biased agonists may hold great promise and seems as the next step in drug development for the treatment of such multifactorial diseases. In this review, we update the present knowledge on dopamine and dopamine receptors and their potential roles in nausea and vomiting. The pre- and clinical evidence provided in this review supports the implication of both dopamine and dopamine receptor agonists in the incidence of emesis. Besides the conventional dopaminergic antiemetic drugs, potential novel antiemetic targeting emetic protein signaling cascades may offer superior selectivity profile and potency.

Successful implementation of an enhanced recovery after surgery (ERAS) protocol reduces nausea and vomiting after infratentorial craniotomy for tumour resection: a randomized controlled trial

BACKGROUND

Infratentorial craniotomy patients have a high incidence of postoperative nausea and vomiting (PONV). Enhanced Recovery After Surgery (ERAS) protocols have been shown in multiple surgical disciplines to improve outcomes, including reduced PONV. However, very few studies have described the application of ERAS to infratentorial craniotomy. The aim of this study was to examine whether our ERAS protocol for infratentorial craniotomy could improve PONV.

METHODS

We implemented an evidence-based, multimodal ERAS protocol for patients undergoing infratentorial craniotomy. A total of 105 patients who underwent infratentorial craniotomy were randomized into either the ERAS group (n = 50) or the control group (n = 55). Primary outcomes were the incidence of vomiting, nausea score, and use of rescue antiemetic during the first 72 h after surgery. Secondary outcomes included postoperative anxiety level, sleep quality, and complications.

RESULTS

Over the entire 72 h post-craniotomy observation period, the cumulative incidence of vomiting was significantly lower in the ERAS group than in the control group. Meanwhile, the incidence of vomiting was significantly lower in the ERAS group on postoperative days (PODs) 2 and 3. Notably, the proportion of patients with mild nausea (VAS 0-4) was higher in the ERAS group as compared to the control group on PODs 2 or 3. Additionally, the postoperative anxiety level and quality of sleep were significantly better in the ERAS group.

CONCLUSION

Successful implementation of our ERAS protocol in infratentorial craniotomy patients could attenuate postoperative anxiety, improve sleep quality, and reduce the incidence of PONV, without increasing the rate of postoperative complications.

TRIAL REGISTRATION

ChiCTR-INR-16009662, 27 Oct 2016, Clinical study on the development and efficacy evaluation of Enhanced Recovery After Surgery (ERAS) in Neurosurgery.

Preclinical toxicity evaluation of JD5037, a peripherally restricted CB1 receptor inverse agonist, in rats and dogs for treatment of nonalcoholic steatohepatitis

JD5037 is a novel peripherally restricted CB1 receptor (CB1R) inverse agonist being developed for the treatment of visceral obesity and its metabolic complications, including nonalcoholic fatty liver disease and dyslipidemia. JD5037 was administered by oral gavage at 10, 40, and 150 mg/kg/day dose levels for up to 34 days to Sprague Dawley rats, and at 5, 20, and 75 mg/kg/day dose levels for 28 consecutive days to Beagle dogs. In rats, higher incidences of stereotypic behaviors were observed in 10 mg/kg females and 40 mg/kg males, and slower responses for reflex and sensory tests were observed only in males at 10 and 40 mg/kg during neurobehavioral testing. Sporadic minimal incidences of decreased activity (males) and seizures (both sexes) were observed in rats during daily clinical observations, without any clear dose-relationship. Male dogs at 75 mg/kg during treatment period, but not recovery period, had an increased incidence of gut associated lymphoid tissue hyperplasia and inflammation in the intestine. In both species, highest dose resulted in lower AUCs indicative of non-linear kinetics. Free access to food increased the plasma AUC∞ by ~4.5-fold at 20 mg/kg in dogs, suggesting presence of food may help in systemic absorption of JD5037 in dogs. Based on the study results, 150 mg/kg/day in rats, and 20 and 75 mg/kg/day doses in male and female dogs, respectively, were determined to be the no-observed-adverse-effect-levels (NOAELs).

Ropinirole eye drops induce vomiting effectively in dogs: a randomised, double-blind, placebo-controlled clinical study

There is a need for an effective and safe emetic agent that dog owners could easily administer to their dogs following veterinary advice in cases of potential poisoning. As a response to this need, a randomised, double-blind, multi-site, clinical field study was performed to assess the efficacy, safety and usability of ropinirole eye drops to induce vomiting in dogs. Ropinirole (target dose 3.75 mg/m²) was applied to eyes of 100 dogs, and 32 dogs received placebo. The drug was administered by the dog owner at a veterinary clinic under the supervision of a veterinarian and led to vomition in 95% of the ropinirole-treated dogs within 30 min. The median time to first vomit was 10 min (range: 3–37 min). None of the dogs receiving placebo vomited in this time period. All owners were able to administer the product and 96% of them assessed the administration to be very easy or easy, which was confirmed by the observing veterinarian. Some ocular signs were seen both with ropinirole and placebo, hyperaemia being the most common. All observed signs were transient and in most cases mild. Ropinirole eye drops provided an effective, safe and reliable means to induce emesis in dogs.

Spotlight on the perioperative use of maropitant citrate

Neurokinin-1 (NK-1) receptors are present in both the central nervous system and peripheral tissues. Substance P (SP) is the major ligand and is involved in multiple processes including pain transmission, vasodilation, modulation of the inflammatory response, as well as the sensory neuronal transmission involved in stress, anxiety, and emesis. The involvement of NK-1 and SP in the vomiting reflex has led to the development of NK-1 antagonists to prevent and treat vomiting in human and veterinary medicine. Maropitant is a potent, selective neurokinin (NK-1) receptor antagonist that blocks the pharmacologic action of SP in the central nervous system. Maropitant is available in both an injectable and tablet formulation and approved for use in dogs and cats for the treatment and prevention of vomiting from a variety of clinical causes and motion sickness. When administered prior to anesthetic premedication, maropitant prevents or significantly decreases the incidence of opioid-induced vomiting and signs of nausea in dogs and cats. Maropitant has also been shown to improve postoperative return to feeding and food intake in dogs. The minimum alveolar concentration of sevoflurage is decreased in both dogs and cats by maropitant, indicating a potential role as an adjunct analgesic, especially for visceral pain. This article will review the background information and literature, including clinical recommendations with respect to the perioperative use of maropitant in canine and feline veterinary patients.

Comparative efficacy of metoclopramide, ondansetron and maropitant in preventing parvoviral enteritis-induced emesis in dogs

The aim of the study was to evaluate the efficiencies of selected anti‐emetic drugs (metoclopramide, ondansetron and maropitant) in preventing vomiting in the treatment of canine parvoviral enteritis. We designed a randomized, prospective clinical study. PVE quick ELISA test‐positive dogs between 4 and 12 months of age were included in the study. Each of metoclopramide, ondansetron, maropitant and control group had 8 dogs. Metoclopramide and ondansetron were administered as 0.5 mg/kg doses three times a day via intravenous route, and maropitant was administered as 1 mg/kg doses once a day subcutaneously. The number and severity of daily vomitings were recorded. All dogs were treated and monitored for five days; treatments were continued until all animals healed. Metoclopramide, ondansetron and maropitant decreased the severity of vomiting from the first day and the vomiting numbers from the third day in PVE treatment. Obtained results showed that maropitant can be used successfully such as metoclopramide and ondansetron, which are frequently used for PVE treatment. At the same time, it was discovered that metoclopramide, ondansetron and maropitant were equally effective in reducing the frequency and severity of vomiting.

Altered states part 2: addressing nausea in canine research subjects

Nausea and emesis can occur for multiple reasons. While research staff can readily empathize with this type of discomfort, proper assessment and treatment can be challenging. In order to provide optimal care for canine research subjects, it is critical that institutions develop a treatment plan and take preemptive measures to control nausea and emesis when they occur.

Fluid and Electrolyte Therapy During Vomiting and Diarrhea

Fluid therapy is generally the most life saving and important therapeutic measure in a critical pet suffering from dehydration due to gastrointestinal losses (vomiting and/or diarrhea). Fluid therapy should be personalized to the patient's history, complaint, physical examination and laboratory findings. It is directed to the patients needs and modified based of the physical and laboratory findings until fluid therapy resuscitation end points are achieved.

Evaluation of an outpatient protocol in the treatment of canine parvoviral enteritis

OBJECTIVE

To compare 2 treatment protocols (standard in-hospital versus modified outpatient) in affecting the duration of treatment or survival of dogs with parvoviral enteritis.

DESIGN

Prospective, randomized study.

SETTING

University teaching hospital.

ANIMALS

Client-owned dogs with naturally acquired parvovirus were randomized to receive either an inpatient (n = 20) or outpatient (n = 20) treatment protocol.

INTERVENTIONS

Both groups received intravenous (IV) fluid resuscitation and correction of hypoglycemia at hospital admission. Following stabilization, basic inpatient interventions included administration of IV fluids, administration of cefoxitin (22 mg/kg IV q 8 h), and maropitant (1 mg/kg IV q 24 h). Basic outpatient interventions (provided in-hospital) included administration of subcutaneous (SC) fluid (30 mL/kg q 6 h), administration of maropitant (1 mg/kg SC q 24 h) and cefovecin (8 mg/kg SC once). Using daily electrolyte and glucose evaluations, dextrose and potassium supplementation was provided intravenously (inpatients) or orally (outpatients) as indicated. Rescue criteria were used in both groups for analgesia and nausea. All dogs were syringe fed a commercial canine convalescence diet (1 mL/kg PO q 6 h) until voluntary appetite returned.

MEASUREMENTS AND MAIN RESULTS

Protocol success, defined as survival to hospital discharge, was 90% (18/20) for the inpatient group compared to 80% (16/20) for the outpatient group (P = 0.66). There was no difference detected in duration of hospitalization for inpatient dogs (4.6 ± 2 days) versus outpatient dogs (3.8 ± 1.8 days, P = 0.20). Metabolic disturbances were frequent in the outpatient group, with 50% of dogs requiring dextrose supplementation and 60% of dogs requiring potassium supplementation.

CONCLUSIONS

An outpatient protocol may be a reasonable alternative for dogs that cannot receive standard in-hospital treatment for parvoviral enteritis. Diligent supportive care and monitoring are still required to optimize treatment of dogs with parvoviral enteritis in an outpatient setting.

Therapeutic Management of Feline Chronic Gingivostomatitis: A Systematic Review of the Literature

Feline chronic gingivostomatitis (FCGS) is a disease characterized by protracted and potentially debilitating oral inflammation in cats, the etiology of which is currently unknown. The purpose of this review is to apply an evidence-based medicine approach to systematically review and critically evaluate the scientific literature reporting the outcome of medical and surgical management of FCGS. Those articles meeting inclusion criteria were reviewed and assigned an "Experimental Design Grade" (EDG) and an "Evidence Grade" (EG) in order to score relative strength of study design and produced data. Studies were evaluated and compared, especially highlighting the treatments, the outcomes, and the therapeutic success rates. This review found a lack of consistency between articles' data, rendering direct comparison of results unreliable. The field of FCGS research, and ultimately patient care, would benefit from standardizing studies by adopting use of a consistent semi-quantitative scoring system and extending follow-up duration. Future researchers should commit to large prospective studies that compare existing treatments and demonstrate the promise of new treatments.

Scientific and Regulatory Policy Committee

Recommendations (best practices) are provided by the Society of Toxicologic Pathology’s Adversity Working Group for making consistent interpretations of test article–related effects as “adverse” and assigning a “no observed adverse effect level” (NOAEL) in nonclinical toxicity studies. Adverse is a term indicating “harm” to the test animal, while nonadverse indicates lack of harm. Adverse findings in the study reports should be defined in relation to effects on the test species used and within the context of the given study. Test article–related effects should be described on their own merits, and decisions to consider them as adverse or nonadverse should be justified. Related effects may be discussed together; in particular, markers of toxicity that are not in and of themselves adverse ideally should be discussed in conjunction with the causal toxicity to determine adversity. Adverse findings should be identified in subreports (clinical data, pathology data, etc.) if sufficient information is available, and/or in the final study report as individual or grouped findings, but study NOAELs should be established at the level of the overall study report. Interpretations such as “not biologically relevant” or “not toxicologically important” should be avoided unless defined and supported by scientific rationale. Decisions defining adverse findings and the NOAEL in final study reports should combine the expertise of all contributing scientific disciplines. Where possible, use of NOAELs in data tables should be linked to explanatory text that places them in context. Ideally, in nonclinical summary documents, NOAELs from multiple studies are considered together in defining the most important adverse responses in the most sensitive species. These responses are then considered along with an understanding of their likely mechanisms, as well as other information such as variability in species sensitivity, comparative pathology, reversibility and progression, kinetics, and metabolism of the test substance to help assess human risk.

Effect of combined doses of Δ(9)-tetrahydrocannabinol (THC) and cannabidiolic acid (CBDA) on acute and anticipatory nausea using rat (Sprague- Dawley) models of conditioned gaping

RATIONALE

Δ(9)-Tetrahydrocannabinol (THC) and cannabidiolic acid (CBDA) found in cannabis both reduce the distressing symptom of nausea, but their combined effects are not understood.

OBJECTIVE

The potential of combined doses of THC and CBDA to reduce acute nausea and anticipatory nausea in rodent models was assessed.

MATERIALS AND METHODS

For acute nausea, the potential of cannabinoid pretreatment(s) to reduce LiCl-induced nausea paired with saccharin was evaluated in a subsequent drug free taste reactivity test, followed by a taste avoidance test. For anticipatory nausea, the potential of the cannabinoid pretreatment(s) to reduce the expression of LiCl-induced contextually elicited conditioned gaping was evaluated.

RESULTS

Combined subthreshold doses of THC (0.01 and 0.1 mg/kg) and CBDA (0.01 and 0.1 μg/kg) reduced acute nausea. Higher doses of THC (1.0, 10 mg/kg) or CBDA (1.0, 10 μg/kg) alone, as well as these combined doses also reduced acute nausea. THC (10 mg/kg) interfered with conditioned taste avoidance, an effect attenuated by CBDA (10 μg/kg). On the other hand, combined subthreshold doses of THC (0.01 and 0.1 mg/kg) and CBDA (0.01 and 0.1 μg/kg) did not suppress contextually elicited conditioned gaping in a test for anticipatory nausea. However, higher doses of THC (1.0, 10 mg/kg) or CBDA (1.0, 10 μg/kg) alone, as well as these combined doses, also reduced anticipatory nausea. Only at the highest dose (10 mg/kg) did THC impair locomotor activity, but CBDA did not at any dose.

CONCLUSIONS

Combined subthreshold doses of THC:CBDA are particularly effective as a treatment for acute nausea. At higher doses, CBDA may attenuate THC-induced interference with learning.

Ondansetron and promethazine have differential effects on hypothermic responses to lithium chloride administration and to provocative motion in rats

We recently reported that provocative motion (rotation in a home cage) causes hypothermic responses in rats, similar to the hypothermic responses associated with motion sickness in humans. Many stimuli inducing emesis in species with an emetic reflex also provoke hypothermia in the rat, therefore we hypothesized that a fall in body temperature may reflect a “nausea-like” state in these animals. As rats do not possess an emetic reflex, we employed a pharmacological approach to test this hypothesis. In humans, motion- and chemically-induced nausea have differential sensitivity to anti-emetics. We thus tested whether the hypothermia induced in rats by provocative motion (rotation at 0.7 Hz) and by the emetic LiCl (63 mg/kg i.p.) have a similar differential pharmacological sensitivity. Both provocations caused a comparable robust fall in core body temperature (−1.9 ± 0.3°C and −2.0 ± 0.2°C for chemical and motion provocations, respectively). LiCl⁻induced hypothermia was completely prevented by ondansetron (2mg/kg, i.p., a 5-HT₃ receptor antagonist that reduces cancer chemotherapy-induced nausea and vomiting), but was insensitive to promethazine (10 mg/kg, i.p., a predominantly histamine-H₁ and muscarinic receptor antagonist that is commonly used to treat motion sickness). Conversely, motion-induced hypothermia was unaffected by ondansetron but promethazine reduced the rate of temperature decline from 0.20 ± 0.02 to 0.11 ± 0.03°C/min (P < 0.05) with a trend to decrease the magnitude. We conclude that this differential pharmacological sensitivity of the hypothermic responses of vestibular vs. chemical etiology in rats mirrors the observations in other pre-clinical models and humans, and thus supports the idea that a “nausea-like” state in rodents is associated with disturbances in thermoregulation.

Effects of maropitant, acepromazine, and electroacupuncture on vomiting associated with administration of morphine in dogs

OBJECTIVE

To evaluate effects of maropitant, acepromazine, and electroacupuncture on morphine-related signs of nausea and vomiting in dogs and assess sedative effects of the treatments.

DESIGN

Randomized controlled clinical trial.

ANIMALS

222 dogs.

PROCEDURES

Dogs received 1 of 6 treatments: injection of saline (0.9% NaCl) solution, maropitant citrate, or acepromazine maleate or electroacupuncture treatment at 1 acupoint, 5 acupoints, or a sham acupoint. Morphine was administered after 20 minutes of electroacupuncture treatment or 20 minutes after injectable treatment. Vomiting and retching events and signs of nausea and sedation were recorded.

RESULTS

Incidence of vomiting and retching was significantly lower in the maropitant (14/37 [37.8%]) group than in the saline solution (28/37 [75.7%]) and sham-acupoint electroacupuncture (32/37 [86.5%]) groups. The number of vomiting and retching events in the maropitant (21), acepromazine (38), 1-acupoint (35), and 5-acupoint (34) groups was significantly lower than in the saline solution (88) and sham-acupoint electroacupuncture (109) groups. Incidence of signs of nausea was significantly lower in the acepromazine group (3/37 [8.1%]) than in the sham-acupoint group (15/37 [40.5%]). Mean nausea scores for the saline solution, maropitant, and sham-acupoint electroacupuncture groups increased significantly after morphine administration, whereas those for the acepromazine, 1-acupoint electroacupuncture, and 5-acupoint electroacupuncture groups did not. Mean sedation scores after morphine administration were significantly higher in dogs that received acepromazine than in dogs that received saline solution, maropitant, and sham-acupoint electroacupuncture treatment.

CONCLUSIONS AND CLINICAL RELEVANCE

Maropitant treatment was associated with a lower incidence of vomiting and retching, compared with control treatments, and acepromazine and electroacupuncture appeared to prevent an increase in severity of nausea following morphine administration in dogs.

Management of acute pancreatitis in dogs: a critical appraisal with focus on feeding and analgesia

Knowledge about acute pancreatitis has increased recently in both the medical and veterinary fields. Despite this expansion of knowledge, there are very few studies on treatment interventions in naturally occurring disease in dogs. As a result, treatment recommendations are largely extrapolated from experimental rodent models or general critical care principles. General treatment principles involve replacing fluid losses, maintaining hydrostatic pressure, controlling nausea and providing pain relief. Specific interventions recently advocated in human medicine include the use of neurokinin-1 antagonists for analgesia and early interventional feeding. The premise for early feeding is to improve the health of the intestinal tract, as unhealthy enterocytes are thought to perpetuate systemic inflammation. The evidence for early interventional feeding is not supported by robust clinical trials to date, but in humans there is evidence that it reduces hospitalisation time and in dogs it is well tolerated. This article summarises the major areas of management of acute pancreatitis in dogs and examines the level of evidence for each recommendation.

Feline gastrointestinal eosinophilic sclerosing fibroplasia: 13 cases and review of an emerging clinical entity

OBJECTIVE

Feline gastrointestinal eosinophilic sclerosing fibroplasia (FGESF) is a recently described inflammatory disease of cats affecting stomach or intestines and draining regional lymph nodes. This study presents clinical and laboratory data on 13 newly described cases from Australia (11) and the UK (two).

OBSERVATIONS

The disease was most often observed in middle-aged cats (median 7 years of age; interquartile range 5-9 years). Ragdolls (7/13) and males (9/13) were overrepresented. Cats generally had a long history of vomiting and/or diarrhoea. Lesions were typically large, hard, non-painful, easily palpable and most commonly situated near the pylorus or ileocaecocolic junction. Lesions were heterogeneous ultrasonographically and on sectioning at celiotomy or necropsy. Masses were hard and 'gritty' on fine-needle aspiration due to internal trabeculae made up of mature collagen bundles. Bacteria were commonly detected within masses (9/13 cases) using either culture or conventional light microscopy and a panel of special stains, and/or fluorescence in situ hybridisation (FISH), although detection often required a diligent search of multiple tissue sections. A consistent bacterial morphology could not be appreciated among the different cases.

OUTCOME

Patients were treated with a variable combination of cytoreduction (debulking and biopsy, to complete surgical resection), immunosuppressive therapy and antimicrobial agents. Many cats had a poor outcome, which was attributable to late diagnosis combined with suboptimal management. It is hoped that suggestions outlined in the discussion may improve clinical outcomes and long-term survival in future cases.

Preclinical Safety of the Root Extract of Polygala tenuifolia Willdenow in Sprague-Dawley Rats and Beagle Dogs

The root of Polygala tenuifolia Willdenow has been used for the treatment of insomnia, depression, and amnesia. However, the toxicological properties of the herb have been overlooked, because it has been used for a long time for various purposes. In this study, we evaluated the preclinical safety of the root extract in rats and beagle dogs. First, the acute oral toxicity was tested in both rats and dogs. In the rats, only one female of 2 g/kg died, but no treatment-related death or clinical and gross findings were observed after the administration. No toxicological changes or mortalities related to the test substance were also observed after the administration in the dogs. Although vomiting, discoloration, or hemorrhage was found in some dogs, there were no serious abnormalities. Second, the subchronic toxicity was investigated in the rats. Two animals were found dead in the female group of 1,000 mg/kg/day, but there were no abnormal findings associated with the test substance. There also were no adverse effects on the clinical signs, body weight, and hematological and biochemical findings. Therefore, our results showed that the acute or subchronic toxicity of the root extract of Polygala tenuifolia might not be toxic to rats and dogs.

Nausea: current knowledge of mechanisms, measurement and clinical impact

Nausea is a subjective sensation, which often acts as a signal that emesis is imminent. It is a widespread problem that occurs as a clinical sign of disease or as an adverse effect of a drug therapy or surgical procedure. The mechanisms of nausea are complex and the neural pathways are currently poorly understood. This review summarises the current knowledge of nausea mechanisms, the available animal models for nausea research and the anti-nausea properties of commercially available anti-emetic drugs. The review also presents subjective assessment and scoring of nausea. A better understanding of the underlying mechanisms of nausea might reveal potential clinically useful biomarkers for objective measurement of nausea in species of veterinary interest.

Effectiveness and adverse effects of the use of apomorphine and 3% hydrogen peroxide solution to induce emesis in dogs

OBJECTIVE

To determine the effectiveness and adverse effects of apomorphine and 3% hydrogen peroxide solution used for emesis in dogs.

DESIGN

Prospective observational study.

ANIMALS

147 dogs that received apomorphine (IV or placed in the conjunctival sac) or 3% hydrogen peroxide solution (PO) to induce emesis after exposure to toxic agents.

PROCEDURES

Data regarding signalment; agent information; type, dose, route, and number of emetic administrations; whether emesis was successful; number of times emesis occurred; percentage of ingested agent recovered; and adverse effects were collected via telephone during American Society for the Prevention of Cruelty to Animals Animal Poison Control Center operations and stored in a database for analysis. Mann-Whitney and Fisher exact tests were used to evaluate emetic success rates.

RESULTS

Apomorphine and 3% hydrogen peroxide solution successfully induced emesis in 59 of 63 (94%) and 76 of 84 (90%) of dogs, respectively. Mean time to onset of emesis after the first dose of emetic was 14.5 and 18.6 minutes when hydrogen peroxide (n = 37) and apomorphine (31) were used, respectively, with mean durations of 42 and 27 minutes, respectively. Mean estimates for recovery of ingested agents were 48% for hydrogen peroxide and 52% for apomorphine. Adverse effects were reported in 16 of 112 (14%) dogs for which information was available.

CONCLUSIONS AND CLINICAL RELEVANCE

3% hydrogen peroxide solution and apomorphine effectively induced emesis in dogs when used as directed. Emesis occurred within minutes after administration and helped recover substantial amounts of ingested agents. Adverse effects of both emetics were considered mild and self-limiting.

Mechanisms, causes, investigation and management of vomiting disorders in cats: a literature review

Vomiting is a common presenting complaint in feline practice. This article differs from previous reviews in that it is an evidence-based review of the mechanisms, causes, investigation and management of vomiting in the domestic cat. Published evidence was reviewed, and then used to make recommendations for clinical assessment, diagnosis, antiemetic drug treatment, dietary management and monitoring of cats presenting with vomiting. The strength of the evidence on which recommendations are made (and areas where evidence is lacking for cats) has been highlighted throughout.

Canine serum amyloid A (SAA) measured by automated latex agglutination turbidimetry is useful for routine sensitive and specific detection of systemic inflammation in a general clinical setting

Canine serum amyloid A (SAA) is a useful diagnostic marker of systemic inflammation. A latex agglutination turbidimetric immunoassay (LAT) was validated for automated measurements. The aim of the study was to evaluate the clinical applicability of SAA measured by the LAT. SAA was measured in 7 groups of dogs with and without systemic inflammation (n=247). Overlap performance was investigated. Diagnostic performance was compared to body temperature and leukocyte markers. Clinical decision limits for SAA were estimated. In dogs with neurological, neoplastic or gastrointestinal disorders (n=143), it was investigated whether a higher proportion of SAA positive dogs could be detected in cases of complications with risk of systemic inflammation. Significantly higher concentrations of SAA were measured in dogs with (range [48.75; 5,032 mg/l]), compared to dogs without systemic inflammation [0; 56.4 mg/l]. SAA was a more sensitive and specific marker of systemic inflammation (area under the receiver-operating characteristic curve (AUC) 1.00), compared to body temperature (0.6) and segmented neutrophils (best performing leukocyte marker, 0.84). A clinical decision limit of 56.4 mg/l was established giving close to perfect discrimination between dogs with and without systemic inflammation. Higher proportions of SAA-positive dogs were observed in dogs with neurological, neoplastic and gastrointestinal disorders with complications known to increase risk of systemic inflammation, compared to uncomplicated cases. The automated LAT makes SAA applicable as a relevant diagnostic marker of systemic inflammation in dogs for routine random-access real-time use in a general clinical setting.

Assessment of anti-depressant effect of nelumbinis semen on rats under chronic mild stress and its subchronic oral toxicity in rats and beagle dogs

BACKGROUND

Previously, we examined the antidepressant effects of Nelumbinis Semen (NS). In this study, we assessed the anti-depressant effects of NS in the forced swimming test and chronic mild stress (CMS) models of depression and its oral toxicity in rats and dogs.

METHODS

In the forced swimming test, NS was intraperitoneally injected before 24 h, 5 h and 1 h of forced swimming test. And the rats were forced to swim for 5 min, the duration of immobility was observed. In CMS models, animals were exposed to a variety of CMS for 8 weeks in order to induce depression-like symptoms. They were treated with NS for the last four weeks of the 8-week CMS and then an open field test was conducted. The anti-depression effects were evaluated based on a measured index, which consisted of visiting counts, start latency, rearing number and grooming time. In the toxicological studies, NS was administered to rats by gavages for 13 weeks at doses of 0, 500, 1000, and 2000 mg/kg/day. To assess the toxicity of NS in beagle dogs, NS was administered orally for 28 days at doses of 0, 500, 1000, 2000 and 4000 mg/kg/day.

RESULTS

400 mg/kg of NS had the lowest immobility times in forced swimming test. And NS significantly reversed the decreased visiting counts, rearing number and grooming time caused by CMS. In addition, NS treatment significantly decreased the start latency. No treatment-related toxicity was detected during 13 weeks administration in rats and 28 days administration in dogs.

CONCLUSIONS

Based on the results of this study and previous reports that have examined the anti-depressive effects of NS, NS holds great promise for use in the treatment of depression without causing any adverse effects or toxicities.

Infarto agudo do miocárdio e injeção intramiocárdica experimental em cães: estudos clínico, enzimático, eletrocardiográfico e ecocardiográfico

Os eventos isquêmicos em cães são incomuns, porém podem estar sendo subnotificados. Avaliou-se o infarto agudo do miocárdio (IAM) clinicamente, por meio de eletrocardiografia (ECG), eletrocardiografia contínua (EC), ecocardiografia (ECO), enzima creatina quinase (CK), enzima creatina quinase fração MB (CK-MB) e anátomo-histologicamente em cães sem raça definida, e observou-se a ocorrência de arritmias após injeção intramiocárdia por EC. O IAM foi obtido após a ligadura da coronária descendente anterior. Os animais apresentaram ao ECO dilatação da câmara esquerda e aumento do índice de desempenho miocárdico. Ao ECG houve desnivelamento de ST nas derivações pré-cordiais V1 e V2. No EC observaram-se arritmias ventriculares graves e supradesnivelamento de ST. As enzimas CK e CK-MB aumentaram significativamente, sendo que os picos de CK-MB e de CK ocorreram seis horas e 12 horas, respectivamente, após o IAM. Na análise histológica constatou-se infarto da parede inferior do ventrículo esquerdo e substituição do tecido muscular por tecido fibroso. Avaliou-se a injeção intramiocárdica por EC que pode servir como via terapêutica cardíaca, não sendo observado aumento das arritmias ventriculares após a injeção no miocárdio infartado. O infarto em cães pode ser detectado pelos exames cardíacos disponíveis, e a injeção intramiocárdica é uma via terapêutica cardíaca possível.

Treatment of extrahepatic congenital portosystemic shunts in dogs - what is the evidence base?

A variety of surgical treatments and medical therapies are recommended for dogs with extrahepatic congenital portosystemic shunts (CPSS). The objective of this review was to assess the evidence base for the management of extrahepatic CPSS in dogs. An online bibliographic search was performed in November 2010 to identify articles relating to the question "Which of the treatment options for extrahepatic CPSS in dogs offers the best short- and long-term outcomes?" Articles were assigned a level of evidence based on a modified grading system. Thirty-eight articles were included in the review. Thirty-six articles were classified as grade 4 and two as grade 5. The timings and methods of assessment of short- and long-term outcomes varied widely between studies. One prospective study (grade 4a) showed that surgically treated dogs survived significantly longer than medically treated dogs. Four retrospective studies (grade 4b) compared the outcome of two surgical techniques but there were no statistically significant differences between treatment groups in terms of complications or outcome. The review found that the evidence base for the treatment of extrahepatic CPSS is weak. There is a lack of evidence of short- and long-term outcomes to recommend one treatment over another.

First-choice therapy for dogs presenting with diarrhoea in clinical practice

Computerised referral histories were reviewed for dogs admitted to the University of Liverpool Small Animal Teaching Hospital between January 2000 and December 2008 with diarrhoea among the clinical signs. A total of 371 cases presenting to the referring veterinary surgeon were included in the study, and information was compiled regarding signalment, clinical signs and treatment given at the initial consultation. Various breeds, ages and sexes were represented. Antibacterials were used in 263 (71 per cent) cases, steroids in 71 (19 per cent) cases and miscellaneous antidiarrhoeal products (including probiotics, prebiotics, adsorbents and antimotility drugs) in 98 (26 per cent) cases. Other drugs used included antiemetics (48 of 371 [13 per cent] cases), gastric protectants (37 of 371 [10 per cent] cases) and sulfasalazine (26 of 371 [7 per cent] cases). Antibacterial administration was positively associated with hyperthermia (odds ratio [OR]=2.97, P=0.012) and anorexia (OR=2.17, P=0.0075), but negatively associated with both weight loss (OR=0.55, P=0.036) and tenesmus (OR=0.43, P=0.035). In contrast, use of antidiarrhoeal products was positively associated with the presence of faecal mucus (OR=1.77, P=0.043), and negatively associated with vomiting (OR=0.57, P=0.025) and weight loss (OR=0.52, P=0.033).