Objective:To describe a case of documented serum sickness in a dog following administration of a single dose of a novel antivenin crotalidae polyvalent. Case Summary:A 4-year-old female neutered mixed breed dog developed recurrent signs of hypersensitivity (swelling, edema, urticaria/hives, gastrointestinal signs, vasculitis) at 1 and 2 weeks following administration of a single unit of a novel antivenin crotalidae polyvalent plasma product. Both episodes were treated with antihistamines and glucocorticoids and signs improved rapidly, with a prolonged course of glucocorticoids and antihistamines administered following the second occurrence. Diagnosis of serum sickness was based on clinical appearance of delayed hypersensitivity following exposure to novel biologic product, absence of other inciting cause of hypersensitivity, complement testing, and skin biopsies confirming vasculitis. New or Unique Information Provided:This case documents the first report of delayed hypersensitivity with a novel antivenin plasma product. This is the only case report of serum sickness to a single unit of antivenin. Additionally, the dog developed recurrence of hypersensitivity following the initial episode at 1 week; appropriate identification and prolonged treatment could have prevented recurrence and additional hospitalization. Cost and benefit analysis should be considered with antivenin administration. K E Y W O R D Sanatomy, anesthesiology, cardiovascular, coagulation, fluid balance

ObjectiveTo report the development of a tension pneumomediastinum during mechanical ventilation of a young Irish Wolfhound with aspiration pneumonia.Case SummaryA 9‐month‐old intact female Irish Wolfhound was presented for clinical signs consistent with aspiration pneumonia. Evaluation of her pedigree and clinical signs prompted suspicion of Irish Wolfhound rhinitis bronchopneumonia syndrome as a contributing factor. Despite supportive care for bronchopneumonia, progressive hypoxemia and increased work of breathing required mechanical ventilation (MV). Development of a pneumothorax 36 hours after initiation of MV necessitated bilateral thoracostomy tubes. Cardiovascular decline persisted despite resolution of the pneumothorax and 1 hour later the dog was humanely euthanized. On necropsy, severe pneumomediastinum was identified without other evidence of barotrauma. Necropsy results suggested tension pneumomediastinum as the cause of pneumothorax and cardiovascular deterioration.New or Unique Information ProvidedPneumomediastinum has not been described in dogs receiving MV. This case highlights the importance of rapid detection of pneumomediastinum during MV, as the complication can quickly become life‐threatening.

To report the incidence and type of peripheral intravenous catheter complications in hospitalised dogs.MethOds: A prospective, observational trial was performed. Peripheral intravenous catheters were monitored for complications. Complications were documented and classified as extravasation, phlebitis, dislodgement, occlusion and line breakage. If phlebitis was present, the Visual Infusion Phlebitis Scale was used to assign a grade (0 to 5). Fisher's exact test was used to compare the type of complications between the critical care unit and the intermediate care unit. A univariate logistic model was used to compare the incidence of complications between the critical care unit and the intermediate care unit and adjusted odds ratios were used to compare the groups.Results: The incidence of peripheral intravenous catheter complications was 24.2% in the Critical Care Unit and 13.1% in the Intermediate Care Unit, with an overall incidence of 19.9%. Phlebitis was the most common peripheral intravenous catheter complication in the Critical Care Unit, and line breakage was the most common complication in the Intermediate Care Unit. Length of hospitalisation and weight had a significant effect on the likelihood of complication. In a multivariable logistic regression model, the odds of a peripheral intravenous catheter complication was not significantly higher in CCU than IMCU, accounting for length of hospitalisation and weight (adjusted odds ratio, 1.84; 95% confidence interval, 0.98 to 3.48).clinical significance: Peripheral intravenous catheter complications are common in hospitalised dogs and may result in an increased expense for owners, failure to deliver prescribed treatments, venous depletion (lack of peripheral vessels for intravenous catheter placement) and pain experienced by the patient. Techniques to reduce peripheral intravenous catheter complications should be further evaluated and may include the use of peripheral intravenous catheter placement and maintenance checklists, use of force-activated separation devices, or patient sedation.

OBJECTIVE To determine whether shock index (SI) positively correlates with percentage blood loss and negatively correlates with cardiac output (CO) in a canine hemorrhagic shock model and whether SI and metabolic markers may be used as end point targets for resuscitation. ANIMALS 8 healthy Beagles. PROCEDURES Between September and December 2021, dogs underwent general anesthesia for experimental induction of hypotensive shock, with the total volume of blood removed, CO, heart rate, systolic blood pressure, base excess, blood pH, and concentrations of hemoglobin, lactate, ionized calcium recorded, and SI calculated at 4 time points (TPs): after anesthetic induction when the dog had been stable for 10 minutes (TP1), 10 minutes after the mean arterial pressure stabilized to a target of 40 mm Hg following jugular removal of up to 60% blood volume to induce hemorrhagic shock (TP2), 10 minutes after autotransfusion of 50% of the removed blood (TP3), and 10 minutes after autotransfusion of the remaining 50% of the removed blood (TP4). RESULTS Mean SI increased between TP1 (1.08 ± 0.35) and TP2 (1.90 ± 0.73) and did not return to the prehemorrhage values for TP3 or TP4. SI correlated positively with percentage blood loss (r = 0.583) and negatively with CO (r = –0.543). CLINICAL RELEVANCE An increase in SI may support diagnosis of hemorrhagic shock; however, SI cannot be used as the sole end point of resuscitation. Significant differences in blood pH, base excess, and lactate concentration suggested they may be useful markers of hemorrhagic shock and need for blood transfusion.

Objective To determine the success rate and complications associated with inducing emesis in dogs that have ingested foreign material. Design Retrospective case series, 2010–2014. Setting Private practice and referral center. Animals Sixty‐one client‐owned dogs that had emesis induced for the treatment of ingestion of foreign material. Interventions None. Measurements and Main Results Emesis was successfully induced in 59 of 61 (97%) dogs administered an emetic. Of those 59 dogs, 46 (78%) produced the foreign body. There were no complications reported in any of the dogs in which emesis was successfully induced. Dogs in which emesis was successfully induced were likely to produce the foreign body (P = 0.01). Conclusion Based on the results of this study, emesis appears to be a safe and effective means for the removal of certain gastric foreign bodies in dogs.

The purpose of this study was to evaluate the pharmacokinetics of intravenous (IV) ondansetron in a population of hospitalized dogs exhibiting clinical signs of nausea. The causes of nausea included pancreatitis, gastroenteritis, endocarditis, chemotherapyinduced nausea, diabetes mellitus and ketoacidosis, acute kidney injury with aspiration pneumonia, pyometra, uroabdomen, neoplasia, and hepatopathy. Twenty-four dogs were randomly assigned to one of the following IV ondansetron protocols: 1 mg/ kg q12h, 0.5 mg/kg q12h, 1 mg/kg q8h, 0.5 mg/kg q8h. Serum was collected at 0, 0.25, 0.5, 1, 2, 4, 8, 16, and 24 h after the first dose, and nausea scores were recorded at multiple time points. Ondansetron and arginine vasopressin (AVP) concentrations were measured via high-performance liquid chromatography coupled to tandem mass spectrometry and ELISA, respectively. Noncompartmental pharmacokinetic modeling and dose interval modeling were performed. Ondansetron displayed linear pharmacokinetics. In the 0.5 mg/kg group, mean C max = 214 ng/ml, AUC 0-8h = 463 ng/ ml*h, and calculated half-life was 1.9 h. In the 1 mg/kg group, mean C max = 541 ng/ml, AUC 0-8h = 1057 ng/ml*h and calculated half-life was 1.6 h. Serum ondansetron concentrations were not significantly different between dogs that required rescue antinausea medication (non-responders) and dogs that did not require rescue therapy (responders). In total, 83.3% of patients in the 0.5 mg/kg q8h, 0.5 mg/kg q12h, and 1 mg/kg q8h groups had improvement in nausea scores. In total, 66.7% of patients in the 1 mg/kg q12h group had improvement in nausea scores. In total, 33% of patients had resolution of nausea in the 0.5 mg/kg q8h, 1 mg/kg q8h, and 1 mg/kg q12h groups, and 16% of patients had resolution of nausea in the 0.5 mg/kg q12h group. AVP concentrations were highly variable and did not correlate with nausea scores.Nausea scores significantly decreased regardless of dosage protocol. AVP was not a reliable biomarker of nausea in this group of dogs.

OBJECTIVE To assess the diagnostic value of the ultrasonographic description of a splenic mass or nodule as cavitated in dogs with nontraumatic hemoabdomen. ANIMALS 106 dogs with a nontraumatic hemoabdomen that underwent abdominal ultrasonography and splenectomy with histologic examination of splenic lesions between 2005 and 2018. PROCEDURES Medical records were reviewed for abdominal ultrasonographic and histologic findings. Diagnostic performance of ultrasonographic description of a splenic mass or nodule as cavitated as evidence of hemangiosarcoma or any malignancy was evaluated. RESULTS Ultrasonographic description of splenic lesions as cavitated had poor diagnostic utility in predicting presence of hemangiosarcoma or malignancy. Sensitivity and specificity of this test were 41.9% (95% CI, 30.5% to 54.3%) and 51.2% (95% CI, 36.8% to 65.4%), respectively, for detecting hemangiosarcoma, with positive and negative predictive values of 55.3% (95% CI, 41.2% to 68.6%) and 37.9% (95% CI, 26.6% to 50.8%), respectively. Results were similar for detecting malignancy. Cavitated lesions outside of the spleen were too rare for statistical analysis to be of value. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that relying on ultrasonographic description of cavitation to diagnose splenic lesions as malignant in dogs with nontraumatic hemoabdomen is unfounded. Other preoperative diagnostic tests may be more valuable in determining short- and long-term prognoses.

OBJECTIVE To determine whether the use of a force-activated separation device (FASD) lowers the incidence risk of peripheral intravenous catheter (PIVC) complications in hospitalized dogs. ANIMALS 367 dogs that were hospitalized and received IV fluids between January 11 and March 25, 2021. PROCEDURES A prospective, randomized controlled clinical trial was performed. Dogs hospitalized and receiving IV fluids for at least 24 hours were randomized to the FASD group or control group. PIVCs were placed following a standardized protocol. Dogs in the FASD group had the FASD device attached to their PIVC according to manufacturer instructions. For both groups, all PIVC complications were documented, and each complication was classified as extravasation, phlebitis, dislodgement, occlusion, or line breakage. RESULTS Results from 367 dogs (FASD group = 180, control group = 187) underwent analysis. The proportion of PIVC complications was significantly (P = .004) lower for the FASD group (8.9% [16/180]) versus the control group (24.6% [46/187]). Following adjustment for differences in hospitalization time, the odds of a dog in the FASD group having a PIVC complication was approximately one-third the odds of those in the control group (OR, 0.33; 95% CI, 0.17 to 0.63; P = .001). CLINICAL RELEVANCE Results indicated that the use of a FASD in hospitalized dogs receiving IV fluids is warranted to lower the incidence of PIVC complications and may also limit patient discomfort, owner expense, and staff time devoted to managing PIVC complications. Further research investigating its use in cats and other species should be considered.