Third degree atrioventricular block and acquired myasthenia gravis in four dogs.

Third degree atrioventricular block was diagnosed in 4 dogs with acquired myasthenia gravis (serum acetylcholine receptor antibody titer > 0.6 nmol/L). All 4 dogs had megaesophagus. Two dogs also had mediastinal thymomas, which were resected. One dog with thymoma received a permanent pacemaker at the same time that it underwent thymectomy; the other did not develop third degree atrioventricular block until 3 months after thymectomy. Both dogs with thymoma died of severe aspiration pneumonitis within 3 months after surgery. The third dog received a permanent pacemaker and was treated with pyridostigmine bromide, but also died of aspiration pneumonitis 1 month after the pacemaker was implanted. The fourth dog was treated with prednisolone and pyridostigmine bromide and improved, but did not become clinically normal. Because third degree atrioventricular block as well as myasthenia gravis can cause signs of weakness, acquired myasthenia gravis should be considered in dogs with idiopathic cardiac conduction disturbances. Likewise, an ECG should be evaluated in dogs with acquired myasthenia gravis.

Hematologic emergencies.

The most common life-threatening hematologic emergencies include hemorrhage and severe anemia. Successful treatment of these conditions depends on the emergency veterinarian having a thorough understanding of the possible etiologies of these conditions, and a systematic approach to diagnosis and therapy. Use of blood component therapy can be a life-saving technique in these patients. The goal of this article is to familiarize the emergency veterinarian with a systematic approach to the diagnosis and treatment of hematologic emergencies.

Pathogenesis and treatment of canine rhinitis.

Unless a systematic approach is used, evaluation of a patient with rhinitis can be frustrating to the veterinary practitioner. A complete differential list for canine rhinitis should include infectious, inflammatory, neoplastic, and traumatic causes. Other causes of rhinitis include dental disease, parasitic infestation, and ciliary dyskinesia. Diagnostic techniques that should be considered when evaluating a patient with rhinitis include obtaining a complete history, performing a thorough physical and oral examination, evaluating the patient's coagulation abilities, cytology and culture of exudate, nasal radiographs, and rhinoscopy. This article describes the pathogenesis and treatment of the various causes of canine rhinitis.

Pathogenesis and treatment of feline rhinitis.

Diagnosis and treatment of feline rhinitis, like canine rhinitis, can be a frustrating experience for the veterinary practitioner. Having sound knowledge of the possible etiologies involved and using a systematic diagnostic approach makes the workup of these challenging cases much easier. Selection of appropriate therapy based on a definitive diagnosis makes treatment rewarding. This article discusses the pathogenesis and treatment of a variety of causes of feline rhinitis.

Controversial issues in drug treatment during cardiopulmonary resuscitation.

The goal of advanced life support in CPR must be to restore and maintain respiratory and hemodynamic effectiveness, and to correct the underlying dysrhythmia. Optimal basic life-support techniques must be continued to meet these goals. Many drugs have been suggested in the treatment of cardiac arrest, but unfortunately, drug effects are inconsistent and resuscitation rates remain low. Epinephrine, atropine, lidocaine, bretylium, and naloxone remain important drugs for consideration in CPR in most animals with cardiac arrest. The best chance of survival remains in early recognition of animals susceptible to arrest and in treatment of the underlying cause.

Respiratory and cardiopulmonary arrest in dogs and cats: 265 cases (1986-1991).

Outcomes of cardiopulmonary arrest and resuscitation in clinically affected dogs and cats have not been adequately studied. We examined the records from 200 dogs and 65 cats that had received cardiopulmonary resuscitation for respiratory or cardiopulmonary arrest; none of the animals had been anesthetized or intubated at the time of arrest, and all had been hospitalized in a veterinary critical care facility. Cardiopulmonary arrest was found to be more common than respiratory arrest in dogs and cats. Hospital discharge rates for animals with cardiopulmonary arrest ranged from 4.1% for dogs to 9.6% for cats, and were consistent with those reported from studies of human beings with cardiopulmonary arrest. Hospital discharge rates for dogs and cats with respiratory arrest were 28% and 58.3%, respectively.