Can isuprel (isoproterenol) drip be used for symptomatic bradycardia?

From the Guidelines

Yes, isoproterenol (Isuprel) drip can be used for symptomatic bradycardia, as recommended by the 2018 ACC/AHA/HRS guideline on the evaluation and management of patients with bradycardia and cardiac conduction delay 1.

Key Considerations

• The typical dosing range for isoproterenol in this context is an infusion of 1-20 mcg/min, based on heart rate response, as outlined in the guideline 1.
• Administration of isoproterenol requires continuous cardiac monitoring and should be done in a critical care setting due to potential side effects such as hypotension, arrhythmias, and myocardial ischemia, especially in patients with coronary artery disease.
• Isoproterenol works as a non-selective beta-adrenergic agonist that increases heart rate by stimulating beta-1 receptors in the heart, making it a temporary measure until more definitive treatment, such as pacemaker placement, can be implemented.

Clinical Context

• Other first-line agents like atropine are typically tried before isoproterenol, as per the guideline recommendations 1.
• The medication should be used cautiously in patients with cardiovascular disease, and the lowest effective dose should be used for the shortest necessary duration to minimize risks.
• The guideline provides a comprehensive approach to managing bradycardia, including the use of isoproterenol, dopamine, epinephrine, and other medications, depending on the underlying cause and clinical presentation 1.

Important Notes

• The dosing and administration of isoproterenol should be tailored to the individual patient's response and clinical condition, with careful monitoring for potential side effects.
• The guideline emphasizes the importance of a thorough evaluation and management approach for patients with bradycardia, including consideration of underlying causes, clinical presentation, and treatment options 1.

From the FDA Drug Label

Isoproterenol Hydrochloride Injection is indicated: To improve hemodynamic status in patients in distributive shock and shock due to reduced cardiac output For bronchospasm occurring during anesthesia

The isuprel (isoproterenol) drip can be used for symptomatic bradycardia, as it is indicated to improve hemodynamic status in patients with reduced cardiac output, which may include those with symptomatic bradycardia. However, the label does not explicitly state this indication.

• The recommended dosage for adults with shock and hypoperfusion states can be adjusted based on heart rate, central venous pressure, systemic blood pressure, and urine flow.
• If the heart rate exceeds 110 beats per minute, consider decreasing or temporarily discontinuing the infusion 2.

From the Research

Isuprel (Isoproterenol) Drip for Symptomatic Bradycardia

• Isoproterenol is widely used in the treatment of symptomatic bradycardia, as stated in the study 3.
• The study 4 mentions that drugs such as atropine, isoproterenol, dopamine, dobutamine, or epinephrine can be used for the acute treatment of bradycardia.
• In the study 5, it is mentioned that symptomatic patients with clonidine-induced bradycardia responded inconsistently to intravenous atropine sulfate therapy, and one patient responded to isoproterenol therapy.

Risks and Considerations

• The study 3 reports a case of myocardial infarction precipitated by the therapeutic use of isoprenaline, highlighting the need for caution in patients with confirmed or suspected coronary artery disease.
• The study 5 identifies patients with renal insufficiency, clinical sinus node dysfunction, and those who have developed bradycardia while taking other sympatholytic agents as being at risk for severe bradycardia during oral clonidine therapy.

Alternative Treatments

• The study 6 describes the use of aminophylline in the treatment of severe symptomatic bradycardia resistant to atropine.
• The study 7 suggests a potential role for glucagon in the treatment of drug-induced symptomatic bradycardia, particularly in the presence of beta-adrenergic blockade and perhaps calcium channel blockade.
• The study 4 presents a case where traditional Chinese medicine (TCM) was used to treat a patient with sinus bradycardia and cardiac sinus arrests, showing remarkable curative effects.