The purpose of this study was to review the effects of
sedatives and
anesthetics in 137 dogs and 13 cats with congenital or acquired
heart disease which were referred for diagnostic, therapeutic, and surgical interventions: correction of
patent ductus arteriosus (PDA-
ligation, 28%), cardiac catheterization with angiogram and angioplasty (22%), pacemaker implantation (18%), exploratory lateral
thoracotomy (8.7%), correction of right aortic arch (ring anomaly, 3.3%), correction of
subvalvular aortic stenosis (2.7%), correction of PDA with coil in patients with
mitral regurgitation and
congestive heart failure (2%),
pericardectomy and removal of heart-base
tumors (2%),
palliative surgery for
ventricular septal defect (VSD, 0.7%), and sick patients with deleterious
cardiac arrhythmias (0.7%). The
anesthetic plan considered the risks of
anesthesia based upon preoperative patient assessment, classification scheme for functional phases of
heart failure, and
anesthetic drug effects of the cardiovascular system. The effects of
sedatives and
anesthetic drugs on determinants of cardiac output are described. The most commonly used drugs for
premedication, induction, and maintenance of
anesthesia were
midazolam-
oxymorphone (20%),
thiopental or
etomidate (30%), and
isoflurane (64%). Prompt
therapy was given to control arrhythmias and provide organ perfusion,
pain relief, muscle relaxation and renal diuresis, using
lidocaine,
dopamine,
fentanyl,
atracurium, and
furosemide in 17.3% 14.7%, 12%, 10%, and 8.7% of animals, respectively. Methods of routine and advanced patient monitoring are described.