ISUPREL (ISOPRENALINE HYDROCHLORIDE)
MODE OF ACTION
- a synthetic sympathomimetic amine, structurally related to Adrenaline, but acts exclusively on beta adrenergic receptors - acts primarily on the heart and smooth muscle of the bronchi, skeletal muscle vasculature and the gastro intestinal tract - isuprel increases cardiac output due to its positive inotropic and chronotropic actions and increases venous return and therefore increases systolic blood pressure, however diastolic blood pressure is decreased so mean blood pressure may decrease. Intravenous infusion of isuprel decreases peripheral vascular resistence Serum half life: approx 3 minutes
INDICATIONS
� - Bradyarrhythmias, atrioventricular block resistant to atropine
� - Complete heart block prior to temporary pacing � - Beta blocker overdose
Note: Isuprel has no role in routine cardiac arrest, it lowers peripheral vascular resistence and renders cardiac massage ineffective at raising aortic blood pressure and hence ineffective at restoring cerebral and coronary artery flow. Isuprel also increases MV02 (myocardial oxygen demand) and may further increase ischaemia in poorly perfused myocardial tissue
ADVERSE REACTIONS
� Arrhythmias, especially Ventricular Tachycardia
� Myocardial ischaemia due to increased MV02
PRESENTATION
Ampoule: 1mg in 5 mls (1000 mcg/ 5 mls or 200mcg/ml)
DOSAGE AND ADMINISTRATION
IV Injection:
Dilute 1ml of isuprel 1mg/5mls to 9mls of sterile water = 200mcg in 10mls Inject 2 mls and repeat every few minutes up to 10 mls
IV infusion: Isuprel 1mg (1 mg = 1000 mcg) is added to 100mls of 5% Dextrose Therefore final concentration is 10 mcg/ml
Dosage range: 1 - 30 mcg/min
IV Infusion dosage table:
mls / hr 1mg isuprel/100mls 5% Dex 3 mg isuprel/100mls 5% Dex 3 0.5mcg/min 1.5 mcg/min 6 1.0 mcg/min 3.0 mcg/min 12 2.0 mcg/min 6.0 mcg/min 18 3.0 mcg/min 9.0 mcg/min 24 4.0 mcg/min 12.0 mcg/min 30 5.0 mcg/min 15.0 mcg/min 36 6.0 mcg/min 18.0 mcg/min 42 7.0 mcg/min 21.0 mcg/min 48 8.0 mcg/min 24.0 mcg/min 54 9.0 mcg/min 27.0 mcg/min 60 10.0 mcg/min 30.0 mcg/min
