Isoproterenol (Isuprel)

Question 1

Classification

Answer 1

Sympathomimetic, pure beta agonist, synthetic catecholamine

Question 2

Mechanism of Action

Answer 2

• Increases BP & cardiac output by increasing the “big 4” through beta-1 stimulation
• Relaxes vascular smooth muscle, decreasing both peripheral vascular resistance & preload through beta-2 stimulation
• Relaxes bronchial smooth muscles through beta-2 stimulation
• Increases ciliary activity, promoting removal of airway secretions

Question 3

Indications

Answer 3

• Symptomatic bradycardia unresponsive to atropine when external pacing is not available or not effective
• Severe status asthmaticus

Question 4

Contraindications

Answer 4

• Tachycardia
• V-Tach
• Cardiac arrest
• AMI
• Hypotension

Question 5

Adverse Effects

Answer 5

• Cardiovascular: Increased myocardial O2 demand, chest pain, ventricular irritability, tachydysrhythmias, v-fib, hyper/hypotension
• Neurological: headache, nervousness, anxiety, excitement, fatigue
• GI: nausea, vomiting

Question 6

Administration

Answer 6

• Adult: IVPB: 2-10 mcg/min. Mix 2 mg in 500 cc D5W or NSS, start at 2-10 mcg/min. Titrate to a pulse of 60-80 & systolic BP of 90-100. Should not exceed 20 mcg/min
• Pediatrics: Not recommended for prehospital use.

Question 7

Special Considerations

Answer 7

• Isuprel is a pure beta-adrenergic agonist
• Field protocols may require a more dilute concentration of 1 mg/500 cc
• Infusion pumps are highly recommended
• Classified as a class 2-b drug, possibly helpful and should be used with caution if at all