Successful ventilatory management of post‐anesthetic airway collapse and hypoxemia in a dog

Abstract Objective: To report a life‐threatening complication (airway collapse) associated with a common procedure (anesthesia) and to describe its successful management. Case Summary: A dog without pre‐existing signs of respiratory disease developed hypoxemia and severe atelectasis in the post‐anesthetic recovery period and was demonstrated, by bronchoscopic examination, to have severe airway collapse. Mechanical ventilation was used to re‐expand collapsed lung units and to prevent re‐collapse. A ventilation strategy designed to minimize airway and alveolar trauma was used. The dog was successfully weaned from the ventilator and made a full recovery. Unique Information Provided: Acute, severe hypoxemia due to airway collapse occurred in the post‐operative period in a dog with no signs of pre‐existing respiratory disease. The dog was successfully managed with short‐term mechanical ventilation. High frequency jet ventilation was used for a diagnostic bronchoscopy.     

Successful cardiopulmonary resuscitation and use of short-term mechanical ventilation following inadvertent ketamine overdose in a cat

Objective: To describe the clinical manifestations and successful outcome following an inadvertent overdose of ketamine to a cat. Case summary: A 4‐year‐old neutered male domestic shorthair cat was evaluated for a urethral obstruction. Because of an inadvertent miscalculation of ketamine, 20 times the intended dose was administered intravenously, which resulted in cardiopulmonary arrest. Cardiopulmonary‐cerebral resuscitation was successful, and short‐term mechanical ventilation, fluids and intensive monitoring were utilized to achieve full recovery and subsequent discharge of the animal. New or unique information provided: Ketamine is a common anesthetic agent used in cats that is considered to have a wide therapeutic index and minimal cardiopulmonary depressant effects at recommended doses. Successful management of inadvertent ketamine overdose has been reported in children, but not in cats. Prompt CPCR and short‐term mechanical ventilation may be necessary to treat a significant ketamine overdose. In cats, yohimbine may act as a partial antagonist of ketamine.     

Treatment of a dog with severe baclofen intoxication using hemodialysis and mechanical ventilation

Objective: This case report describes the successful management of a dog with coma and respiratory depression due to severe baclofen intoxication. Case summary: A Doberman Pinscher mixed breed dog ingested 500 mg (20 mg/kg) of baclofen. Signs of severe intoxication included coma and profound respiratory muscle weakness. The dog was supported with positive pressure ventilation and treated with one session of hemodialysis. Weaning from the ventilator was achieved within 4 hours of hemodialysis, and recovery from coma occurred over the following 12–36 hours. The dog regained full neurologic function and was normal at discharge following 3 days of hospitalization. New or unique information provide: Severe central nervous system depression and respiratory depression due to baclofen intoxication can be life threatening. In addition to other supportive care, hemodialysis may hasten recovery and ventilatory support may be essential to achieve a positive outcome. With successful treatment, toxicity can be decreased and the associated life‐threatening central nervous system and ventilatory depression can resolve. Prognosis for return of normal function is excellent.     

Successful management of severe hypoventilation and hypercapnia in an alpaca (Vicugna pacos) with short‐term mechanical ventilation

Objective – To describe the successful management of an alpaca with severe hypoventilation and hypercapnia, suspected to be secondary to an anesthesia‐related event. Case Summary – A 3‐year‐old, female alpaca underwent a routine eye enucleation under general anesthesia after traumatic globe perforation. Severe hypoventilation and associated hypercapnia developed postoperatively resulting in a severe primary respiratory acidosis. The awake alpaca was supported with positive‐pressure ventilation for approximately 20 hours before successful weaning. Recovery to hospital discharge occurred over the subsequent 5 days with the alpaca regaining apparently normal respiratory function. New or Unique Information Provided – To the knowledge of the authors, this is the first report describing positive‐pressure ventilation of an alpaca in the veterinary literature. In this case of severe hypoventilation, ventilatory support was essential to the positive outcome. As South American camelids continue to increase in popularity there may be an increased demand for high‐quality and sophisticated veterinary care for these animals. Mechanical ventilation can be used to help restore and maintain normal PO₂, PCO₂, and respiratory acid‐base status in alpacas with ventilatory dysfunction.     

Feline adrenal disorders

Although only recently discovered, feline adrenal disorders are becoming increasingly more recognized. Feline adrenal disorders include diseases such as hyperadrenocorticism (Cushing's syndrome) and hyperaldosteronism (Conn's syndrome). The clinical signs of feline hyperadrenocorticism, which include unregulated diabetes mellitus and severe skin atrophy, are unique to the cat. Other signs of feline hyperadrenocorticism, such as potbellied appearance, polydipsia, polyuria, and susceptibility to infections are also seen in dogs with hyperadrenocorticism. Conn's syndrome has only recently been described in the cat and is in fact more common in cats than in dogs. Characterized by severe hypokalemia, hypertension, and muscle weakness, Conn's syndrome may be misdiagnosed as renal failure. The clinician should become familiar with the clinical signs of adrenal disorders in cats and the common diagnostic tests used to diagnose these syndromes in cats as they differ from those in the dog. Treatment of feline adrenal disorders may be challenging; the clinician should become familiar with common drugs used to treat adrenal disorders in cats.     

Primary hyperaldosteronism in the cat: a series of 13 cases

Thirteen cases of feline primary hyperaldosteronism were diagnosed based on clinical signs, serum biochemistry, plasma aldosterone concentration, adrenal imaging and histopathology of adrenal tissue. Two cases presented with blindness caused by systemic hypertension, whilst the remaining 11 cases showed weakness resulting from hypokalaemic polymyopathy. Elevated concentrations of plasma aldosterone and adrenocortical neoplasia were documented in all cases. Seven cases had adrenal adenomas (unilateral in five and bilateral in two) and six had unilateral adrenal carcinomas. Three cases underwent medical treatment only with amlodipine, spironolactone and potassium gluconate; two cases survived for 304 and 984 days until they were euthanased because of chronic renal failure, whilst the third case was euthanased at 50 days following failure of the owner to medicate the cat. Ten cases underwent surgical adrenalectomy following a successful stabilisation period on medical management. Five cases remain alive at the time of writing with follow-up periods of between 240 and 1803 days. Three cases were euthanased during or immediately following surgery because of surgical-induced haemorrhage. One cat was euthanased 14 days after surgery because of generalised sepsis, whilst the remaining cat was euthanased 1045 days after surgery because of anorexia and the development of a cranial abdominal mass. It is recommended that primary hyperaldosteronism should be considered as a differential diagnosis in middle-aged and older cats with hypokalaemic polymyopathy and/or systemic hypertension and should no longer be considered a rare condition.     

Primary mycoplasma pneumonia associated with reversible respiratory failure in a cat

A young adult cat was evaluated for respiratory failure. Diagnostic testing, including computed tomography and culture, documented a primary Mycoplasma species pneumonia. The cat was treated aggressively with supportive care, including mechanical ventilation and appropriate antibiotics including doxycycline, and made a complete recovery. This is a unique case in respect of the severity of the Mycoplasma species pneumonia as well as the cat's recovery from severe lung injury.     

Coma and respiratory failure due to moxidectin intoxication in a dog

Objective: To describe the clinical consequences following ingestion by a dog of a moxidectin‐containing equine deworming product. Few reports exist concerning the treatment and outcome of severe moxidectin toxicity. Treatment, known factors influencing intoxication, and prognosis are reviewed. Case summary: A 10‐month‐old female Border Collie ingested an unknown quantity of a moxidectin‐containing equine deworming product several hours before presentation. Severe neurological signs subsequently developed and included: ataxia, seizures, coma, and respiratory failure. The dog was treated with supportive care including intravenous fluids, activated charcoal, and positive pressure ventilation. Normal spontaneous respiration returned in 34 hours and the patient was discharged 58 hours after ingestion. Full recovery occurred within 1 week of intoxication. New information provided: This report describes moxidectin intoxication and associated respiratory failure in a dog that required mechanical ventilation. The dog's recovery was rapid. Despite severity of signs, the prognosis for patients with moxidectin intoxication is good with appropriate supportive care.     

Uveitis associated with septic peritonitis in a cat

Objective – To report a case of bilateral uveitis believed to be a consequence of septic peritonitis in a 19‐month‐old cat. Case Summary – Bilateral anterior uveitis with suspicion of extension to the posterior segment was documented in a previously healthy young cat during hospitalization for severe septic peritonitis. Based on medical history and other findings uveitis was believed to result from concurrent abdominal sepsis, due either to metastatic seeding of bacterial organisms or to effects of bacterial toxins and inflammatory mediators on the blood‐aqueous barrier. The cat was surgically and medically managed, and made a full recovery with respect to both his ocular and his abdominal disease. New or Unique Information Provided – Ocular complications secondary to systemic sepsis are well documented in people but seldom reported in the veterinary literature. To the authors' knowledge this is the first report of uveitis linked to septic peritonitis in any veterinary species and the first to report sepsis‐related uveitis in a cat. Ocular inflammatory disease in the context of critical illness deserves attention as a potential significant source of morbidity. The development of ocular inflammatory disease may serve as a sentinel lesion for systemic sepsis and other life‐threatening conditions.     

What is your diagnosis? Abdominal mass aspirate in a cat with an increased Na:K ratio

Abstract: A 13‐year‐old domestic shorthair cat was presented for evaluation of pollakiuria. Laboratory abnormalities included mild hypercholesterolemia, moderate hypertriglyceridemia, and a mild increase in the Na:K ratio (43, reference interval 32–41). Abdominal ultrasonography revealed urinary calculi and a soft tissue mass between the right caudate liver lobe and the right kidney. Surgery was done to remove the cystic calculi, and aspirates of the mass were obtained. Cytologic specimens contained a population of large, round to angular cells with round nuclei, coarse irregularly stippled chromatin, 1–2 prominent round to angular nucleoli, and abundant pale basophilic cytoplasm distended by numerous well‐delineated vacuoles. Rare binucleated cells and micronuclei, and moderate anisocytosis, anisokaryosis, and anisonucleoleosis were noted. The cytologic interpretation was adrenal neoplasia, consistent with adrenal carcinoma. Approximately 4 months later, the cat developed vomiting, dehydration, weakness, and cervical ventroflexion. Serum biochemical alterations at that time included marked hypokalemia (2.4 mmol/L, reference interval 3.4–5.6 mmol/L) and a markedly increased Na:K ratio (65, reference interval 32–41). Mean systolic blood pressure was 205 mmHg. Surgical removal of the mass was accomplished via right adrenalectomy and a diagnosis of adrenal carcinoma was confirmed histologically. Plasma aldosterone concentration (measured preoperatively) was 1358 pmol/L (reference interval 194–388 pmol/L). Primary hyperaldosteronism caused by a functional adrenal carcinoma is an uncommon condition in cats.     

Use of abdominal ultrasonography in the diagnosis of primary hyperaldosteronism in a cat

A 13-year-old castrated male cat was examined because of a 2-week history of weakness, cervical ventroflexion, and dysphagia. Clinicopathologic abnormalities included hypokalemia and high serum creatine kinase activity. Abdominal ultrasonography revealed a 15-mm spherical mass in the area of the left adrenal gland. Plasma aldosterone concentration was high, and plasma renin activity was low. Findings were diagnostic of primary hyperaldosteronism. The cat responded well to intravenous and oral potassium supplementation while in the hospital. The owner declined surgery; therefore, repeated follow-up abdominal ultrasonography was recommended. The cat did well clinically with medical management alone until day 334, when it was lost to follow-up.     

Idiopathic hyperaldosteronism in a dog

Idiopathic hyperaldosteronism was diagnosed in an 8-year-old castrated male Yorkshire Terrier, based on increased concentration of plasma aldosterone, hypertension, hypernatremia, decreased natriuresis, hypokalemia, and hyperkaluria. Unilateral adrenalectomy was performed after visualization of a nodule on the right adrenal gland. Hyperplasia of the zona glomerulosa and increased postoperative aldosterone concentrations supported the diagnosis of idiopathic hyperaldosteronism.     

Congenital lobar emphysema in a kitten

A five‐month‐old ragdoll cat presented with severe respiratory signs, unresponsive to medical therapy. Hyperinflation of the right middle lung lobe was diagnosed with radiography and computed tomography. Lung lobectomy following a median sternotomy led to full recovery. Histopathological analysis revealed lobar emphysema and, based on the animal's age, congenital lobar emphysema was considered the most likely diagnosis.     

Full recovery after cardiac arrest secondary to accidental iatrogenic venous air embolism in a cat

Objective – To describe the successful management of cardiac arrest following accidental venous air embolism (VAE) in a cat. Case Summary – A 3‐year‐old spayed female domestic shorthair cat, weighing 4 kg, was presented for continuation of its chemotherapy protocol. The cat was inadvertently administered approximately 5.5 mL of air IV during initiation of fluid therapy. Immediate cardiac arrest resulted and CPR successfully achieved return of spontaneous circulation. The cat was discharged 5 days later and is reportedly clinically normal 7 months post‐discharge. New or Unique Information Provided – VAE has been rarely reported in the veterinary literature. This is the first report of a cat surviving cardiac arrest secondary to VAE.     

Extravasation injury associated with parenteral nutrition in a cat with presumptive gastrinomas

Objective – To describe the pathologic consequences of parenteral nutrition (PN) extravasation into the mediastinum of a cat. Case Summary – An 8‐year‐old domestic short hair cat with persistent vomiting and anorexia was initiated on PN for nutritional support. PN was being administered at a rate of 12.9 mL/h when inadvertent jugular catheter migration resulted in thrombophlebitis and cellulitis and 40–80 mL of PN extravasated into the SC and mediastinal tissues. The cat was euthanized 36 hours after the extravasation of PN due to poor prognosis related to the gastric complications associated with a presumed primary gastrinoma. Grossly there was excessive mediastinal lymphatic drainage and pronounced edema in the cervical SC and mediastinal tissue. Histopathologic examination of the PN‐extravasated area revealed a severe mixed inflammatory reaction, represented by a severe neutrophilic and mild histiocytic infiltrate with lymphoplasmacytic perivascular cuffing. No bacterial agents were observed or cultured from this area. Unique Information Provided – This is the first case report of a foreign body‐type reaction due to extravasation of PN (extravasation injury) in a cat. Extravasation of PN is not without pathologic consequence, and can result in a severe inflammatory reaction in affected tissues.     

Use of a Baerveldt gonioimplant for secondary glaucoma in a horse

This case report describes the surgical placement of a Baerveldt glaucoma shunt in the right eye of a 14‐year‐old Arabian gelding. The glaucomatous right eye was refractory to aggressive medical and repeated surgical therapies yet maintained functional vision. Despite the need for intensive post operative management and continued daily topical therapy, shunt placement surgery was successful at maintaining normotension and vision for a period of 402 days. This is the first report of long‐term successful glaucoma filtration surgery in this species. Further studies are warranted to evaluate long‐term success of glaucoma shunt placement in equine glaucoma cases.     

Regression of hypertrophic osteopathy in a cat after surgical excision of an adrenocortical carcinoma

A 12-year-old, spayed, female domestic shorthair cat was diagnosed with severe and extensive hypertrophic osteopathy of the appendicular skeleton. Diagnostic ultrasound detected a mass lesion in the right adrenal gland. A right adrenalectomy was performed, and histopathological examination confirmed an adrenocortical carcinoma. No radiographic evidence of pulmonary metastasis was found on initial presentation or recheck thoracic radiographs taken 15 weeks later. Almost complete regression of periosteal new bone formation occurred 15 weeks following the successful surgical removal of the adrenal tumor.