Page 227 - Clinical Small Animal Internal Medicine

19 Management of Heart Failure 195

Table 19.2 Commonly used drugs for the treatment of acute heart failure
VetBooks.ir Drug Indications Dose Comments/Adverse Effects

Diuretics
Furosemide Relief of congestion Dog: 2–4 mg/kg IV/IM/SC q2–4h; Azotemia, dehydration
0.66 mg/kg IV bolus followed by Electrolyte disturbances
0.66 mg/kg/h CRI Monitor renal function
Cat: 1–2 mg/kg IV/IM/SC q2–4h Repeated doses based on respiratory
rate and other signs
Vasodilators
ACE Anti‐RAAS Enalapril Azotemia, hypotension
inhibitor Hypertension Dog/Cat: 0.5 mg/kg q12–24h Monitor renal function
Benazepril Initiation might be delayed until acute
Dog/Cat: 0.25–0.5 mg/kg q12–24h congestion resolved
Lisinopril
Dog: 0.25–0.5 mg/kg q24h
Ramipril
Dog: 0.25 mg/kg q24h
Imidipril
Dog: 0.25–0.5 mg/kg q24h
Sodium Hypertension Dog: 1–10 μg/kg/min CRI Hypotension, monitor blood pressure
nitroprusside Afterload reduction Light sensitive
Preload reduction Typically only used for 12–48 h
Nitroglycerin Afterload reduction Dog: 1–10 μg/kg/min CRI Hypotension, monitor blood pressure
Preload reduction Typically only used for 12–48 h
Hydralazine Hypertension Dog: 0.2–2.0 mg/kg q12h Hypotension
Afterload reduction Gastrointestinal signs
Sildenafil Pulmonary Dog: 1–3 mg/kg q8h Variably effective
hypertension Expensive
Positive inotropes
Dopamine Poor contractility Dog: 1–10 μg/kg/min CRI Tachycardia, arrhythmias
Used only for 12–48 h
Dobutamine Poor contractility Dog: 2.5–10 μg/kg/min CRI Tachycardia, arrhythmias
(less than dopamine)
Used only for 12–48 h
Pimobendan Poor contractility Dog: 0.25 mg/kg q12h Contraindicated if outflow
Afterload reduction 0.15 mg/kg IV once obstruction present
Digoxin Poor contractility Dog: 0.005–0.0075 mg/kg q12h Long half‐life
Supraventricular Cat: 0.03125 mg/cat q24–48h Monitor serum levels
tach Gastrointestinal signs
Typically only used if atrial fibrillation
is present
ACE, angiotensin converting enzyme; CRI, constant rate infusion; IM, intramuscular; IV, intravenous; RAAS, renin‐angiotensin‐aldosterone
system; SC, subcutaneous.

initial presentation, and can help guide the initial or sub- imbalances, or acute kidney injury, particularly if preex-
sequent dosing strategy. In the majority of instances, isting renal dysfunction is present, is the main limiting
mild azotemia, electrolyte abnormalities, increased total factor regarding the dose and frequency of diuretic
protein, loss of body weight, and other signs of volume administration. In cases where diuretic therapy results in
depletion will be detected after the first 18–24 hours of these signs, temporary cessation of diuretic administra-
diuretic therapy. In many cases, mild increases in BUN tion along with replacement fluids administered either
or creatinine and mild clinical dehydration are noted and SC or IV might be needed.
do not necessitate complete cessation of the diuretic In treating acute CHF, clinicians continuously weigh
therapy. The possibility of severe azotemia, electrolyte hydration status and renal function against the degree of