Rebound hyperkalemia in a dog with albuterol toxicosis after cessation of potassium supplementation.

OBJECTIVE: To describe the presentation of rebound hyperkalemia as a delayed side effect of albuterol toxicity in a dog. CASE SUMMARY: A 3-year-old female neutered mixed-breed dog was presented for albuterol toxicosis that led to a severe hypokalemia, hyperlactatemia, and hyperglycemia. The dog also experienced sinus tachycardia and generalized weakness. Treatment was instituted with intravenous fluid therapy and potassium supplementation, and the dog was monitored with a continuous electrocardiogram. Resolution of hypokalemia was documented 12 hours after initial presentation, at which time fluid therapy and potassium supplementation were discontinued. There were no further periods of sinus tachycardia, but instead the dog developed ventricular ectopy with rapid couplets (instantaneous rates of 300/min). An echocardiogram revealed normal cardiac size and function. Twenty-four hours after presentation, the patient developed severe hyperkalemia, despite discontinuation of fluids and potassium supplementation for 12 hours. Serial venous and urinary electrolytes were performed for determination of the fractional excretion of electrolytes. These data confirmed rebound hyperkalemia (7.0 mmol/L), consistent with a markedly increased fractional excretion of potassium, and secondary to the release of potassium from inside the cells. Fluid therapy with dextrose supplementation was provided until 36 hours postpresentation. The hyperkalemia resolved, and the dog was discharged after 44 hours of hospitalization. NEW OR UNIQUE INFORMATION PROVIDED: This case documents rebound hyperkalemia following treatment of albuterol toxicosis in a dog. This case highlights the importance of understanding the distribution of total body potassium when treating serum hypokalemia. Transcellular shifts of potassium, as in the case of albuterol toxicosis, can lead to rebound hyperkalemia even after discontinuation of potassium supplementation. This case further explores the utility of fractional excretion of electrolytes in elucidating the etiology and management of electrolyte disturbances.

Successful management of doxorubicin overdose and extravasation in a dog with lymphoma.

A dog was hospitalized after accidental overdose and extravasation of doxorubicin. With supportive care and dexrazoxane, systemic toxicity resolved by Day 9 and extravasation injury by Day 36. This case demonstrates that, with treatment, dogs can survive doxorubicin overdose and extravasation. The report also highlights the importance of checking the dose of chemotherapeutic agents and preventing extravasation.

Gestion réussie d'une surdose à la doxorubicine et de l'extravasation chez un chien atteint d'un lymphome. Un chien a été hospitalisé après une surdose accidentelle et l'extravasation de doxorubicine. Avec des soins de soutien et de la dexrazoxane, la toxicité systémique s'est résorbée au Jour 9 et la blessure d'extravasation au Jour 36. Ce cas démontre que, avec un traitement, les chiens peuvent survivre à une surdose de doxorubicine et à l'extravasation. Ce rapport souligne aussi l'importance de la vérification de la dose d'agents chimiothérapeutiques et de la prévention de l'extravasation.(Traduit par Isabelle Vallières).

Postoperative Hemostasis Monitoring and Management.

Although postoperative hemorrhage is an understood sequela, surgery also elicits an inflammatory response that may result in a hypercoagulable state and risk for venous or arterial thromboembolism. Postoperative venous thromboembolism is well documented in humans and is multifactorial in nature; however, evidence for its presence in veterinary medicine remains sparse. There is no consensus on the ideal type, dose, and duration of thromboprophylactic therapy in the perioperative period. Regardless, coagulation perturbations secondary to surgical stress are important considerations for the perioperative patient to reduce the possible fatal risks of hemorrhage or thrombosis.

Feasibility of flotation concentration of fungal spores as a method to identify toxigenic mushrooms.

PURPOSE: Mushroom poisoning is a recurring and challenging problem in veterinary medicine. Diagnosis of mushroom exposure in animals is hampered by the lack of rapid diagnostic tests. Our study evaluated the feasibility of using flotation concentration and microscopic evaluation of spores for mushroom identification. Evaluation of this method in living animals exposed to toxigenic mushrooms is limited by ethical constraints; therefore, we relied upon the use of an in vitro model that mimics the oral and gastric phases of digestion. METHODS: In our study, mycologist-identified toxigenic (poisonous) and nontoxigenic fresh mushrooms were collected in North Carolina, USA. In phase 1, quantitative spore recovery rates were determined following magnesium sulfate, modified Sheather's sugar solution, and zinc sulfate flotation (n=16 fungal species). In phase 2, mushrooms (n=40 fungal species) were macerated and digested for up to 2 hours in a salivary and gastric juice simulant. The partially digested material was acid neutralized, filtered, and spores concentrated using zinc sulfate flotation followed by microscopic evaluation of spore morphology. RESULTS: Mean spore recovery rates for the three flotation fluids ranged from 32.5% to 41.0% (P=0.82). Mean (± standard error of the mean) Amanita spp. spore recovery rates were 38.1%±3.4%, 36.9%±8.6%, and 74.5%±1.6% (P=0.0012) for the magnesium sulfate, Sheather's sugar, and zinc sulfate solutions, respectively. Zinc sulfate flotation following in vitro acid digestion (phase 2) yielded spore numbers adequate for microscopic visualization in 97.5% of trials. The most common spore shapes observed were globose, spiked, elliptical, smooth and reticulate. CONCLUSION: Flotation can concentrate mushroom spores; however, false negative results can occur. Spore morphology could not be used to differentiate species of mushroom-forming fungi since the spore shape and surface characteristics seen in the present study were often observed with multiple species of mushroom-forming fungi.