Naslov
Stabilization of the congestive heart failure patient in the ER

Autori
Torti, Marin

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, prošireni sažetak, stručni

Izvornik
Book of Abstracts of the 2nd International Veterinary Specialties Symposium - Emergency Treatments in Small Animals / Matičić, Dražen - Zagreb : Hrvatska akademija znanosti i umjetnosti (HAZU), 2017, 4-5

Skup
2nd International Veterinary Specialties Symposium - Emergency Treatments in Small Animals

Mjesto i datum
Zagreb, Hrvatska, 27.06.207

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
congestive heart failure, dog, cat, stabilization, treatment

Sažetak
Emergency veterinarians commonly care for canine and feline patients with congestive heart failure (CHF). Depending on the primary cause and severity of the cardiac disease, clinical signs can vary from patient to patient and are not pathognomonic for cardiovascular disease. Clinical signs in patients with CHF may include weakness and exercise intolerance, cough, lethargy, inappetence, vomiting, tachypnea, respiratory distress, syncope, or collapse. CHF is often presumptively diagnosed based on a patient's primary presenting complaints, signalment, a thorough history, and physical examination findings. In dogs the most common cause of CHF are acquired heart diseases, in the majority of cases degenerative mitral valve disease and dilated cardiomyopathy. One must not forget that congenital heart diseases, most often patent ductus arteriosus, as well as bacterial endocarditis and myocarditis can lead to the development of CHF. Also, severe cardiopulmonary dirofilariasis or cardiac tamponade can also potentially lead to the development of CHF. Cardiomyopathies are the far most common cause of CHF in cats. The most common form of feline cardiomyopathy is hypertrophic cardiomyopathy, followed by restrictive/unclassified cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy, the rarest form of feline cardiomyopathies. Other possible causes of CHF in cats include hyperthyroidism, myocarditis/endocarditis, and acquired valvular disease. Generally speaking, the key elements of successful CHF patient stabilization include avoidance of stressful situations, rest, oxygen supplementation, intensive diuresis and/or paracentesis. Other possible interventions include heart rate control (usage of antiarrhythmic drugs), positive inotropic support, and antithrombotic therapy. Fluid therapy is almost never a therapeutic option in CHF patient, the only exception being severely dehydrated patient where fluids are used extremely judiciously. Emergency stabilisation is directed toward management of congestion, and often includes oxygen therapy, minimisation of stress, and aggressive diuretic therapy. Cats in congestive heart failure often present with pleural effusion, so in cases of moderate to large volumes of pleural effusion thoracentesis is indicated. The goal of thoracentesis should not be complete removal of effusion but to relieve signs of respiratory distress. Furosemide is probably the most important drug for the management of acute CHF and currently is the diuretic of choice for management of severe pulmonary oedema in dogs and cats. In animals with acute severe CHF, high doses of furosemide are often required, given as intravenous bolus or continuous rate infusion. The definitive dose of furosemide required by an individual animal is hard to define, but for dog doses of up to 4 mg/kg, and cat 3 mg/kg every 1-2 hours are required. Continued use of furosemide commonly causes azotaemia and electrolyte depletion (hypokalaemia). In animals with CHF and low cardiac output, as is the case in DCM, positive inotropic support is indicted. Most commonly used drugs are dobutamine and pimobendan. Dobutamine, a sympathomimetic and ß1 receptor agonist, is most commonly given as a continuous rate infusion, because of dobutamine’s short half-life. In dogs, the infusion rate is adjusted upward from 2.5 µg/kg/min (at 2.5 µg/kg increments) until signs of improved cardiac function are apparent (e. g. increased systemic blood pressure, warm limbs, normal CRT duration). Increases in heart rate greater than 20% above baseline or heart rates >190 bpm or occurrence of arrhythmia dictates dose reduction. Pimobendan is a calcium sensitizing drug and phosphodiesterase 3 inhibitor possessing positive inotropic and vasodilating effects. It has been studied in dogs with chronic valvular disease and dogs with dilated cardiomyopathy, where its use results in significant clinical improvement. Pimobendan is also available as solution for injection (Vetmedin®, solution for injection, 0, 75 mg/ml, Boehringer Ingelheim), and as such can be administered in emergency patients. The dosage of Vetmedin® solution is 0.15 mg/kg intravenously. It should be administered only once, and therapy should be continued with peroral administration of pimobendan. In certain cases, mechanical ventilation is desirable in order to avoid respiratory muscle fatigue, and initiate positive end-expiratory pressure to help mobilize oedema while other therapies take effects. Most animals with CHF markedly improve within 24 to 48 hours after initiation of stabilization. Hence, if improvement is not detected, both the diagnosis and current therapeutic plan should be reconsidered.

Izvorni jezik
Engleski

Znanstvena područja
Veterinarska medicina

POVEZANOST RADA