Pharmacology Antidysrhythmics and Bronchodilators

Adenosine (Adenocard)

• Class: Antidysrhythmic
• Mechanism of Action (MOA): Slows AV node conduction, dilates coronary and peripheral vessels. Short half-life (10-12 seconds)
• Indications: Narrow complex tachycardias, supraventricular tachycardia (SVT)
• Contraindications: Second and third-degree AV blocks, caution with asthma history.
• Side Effects: Transient asystole, chest pain, shortness of breath (SOB), flushing
• Dosage (Adult): 6mg rapid IV push, followed by 20ml NS. If no response, 12mg rapid IV push, followed by 20 ml NS. May repeat a third time at 12mg rapid IV push.
• Pediatric: Base contact only

Albuterol (Proventil)

• Class: Sympathomimetic Bronchodilator
• MOA: Beta-2 adrenergic stimulant, relaxes bronchial smooth muscle
• Indications: Bronchospasm, asthma, emphysema, bronchitis
• Contraindications: Hypersensitivity, caution with heart failure (CHF) patients
• Side Effects: Anxiety, dizziness, tachycardia, palpitations, nausea
• Dosage (Adult): 2.5mg nebulized over 5-15 minutes at 6-8 LPM. May repeat twice.
• Pediatric: Same as adult dose

Aspirin (Bayer, ASA)

• Class: Anti-platelet
• MOA: Inhibits platelet aggregation by blocking thromboxane formation
• Indications: Chest pain of unknown cause, myocardial infarction (MI), transient ischemic attack (TIA)
• Contraindications: History of GI bleeding, intracranial hemorrhage, hypersensitivity, recent major surgery, prior thrombosis, AAA
• Side Effects: Nausea, vomiting, hemorrhage
• Dosage (Adult): 325mg PO (4 x 81mg tablets)
• Pediatric: Not indicated

Atropine Sulfate

• Class: Parasympatholytic Agent
• MOA: Blocks acetylcholine receptors, increasing heart rate
• Indications: Bradycardia, organophosphate poisoning
• Contraindications: Myocardial infarction (MI), 2nd & 3rd degree AV blocks, children (8 & under in cardiac emergencies)
• Side Effects: Increased heart rate, blood pressure
• Dosage (Adult): Bradycardia: 0.5mg IV, may repeat every 5 minutes up to 3mg (or 0.04mg/kg). Organophosphate poisoning 2mg IV, repeat in 2mg increments if needed.
• Pediatric: Not indicated

Atropine (Atrovent)

• Class: Parasympatholytic Bronchodilator
• MOA: Blocks acetylcholine receptors, bronchodilating and drying respiratory secretions.
• Indications: Acute bronchospasms
• Contraindications: Hypersensitivity, peanut/soy allergies
• Side Effects: Nausea, vomiting, nosebleeds (epistaxis), nervousness, headache
• Dosage (Adult): 0.5mg nebulized over 5-15 minutes at 6-8 LPM. One dose only.
• Pediatric: One dose only (0.25mg 1-12 months; 0.5mg 1-14 years).

Calcium Chloride

• Class: Electrolyte
• MOA: Increases myocardial contractile force and enhances ventricular excitability.
• Indications: Calcium channel blocker overdose/poisoning
• Contraindications: Ventricular fibrillation (V-fib), hypercalcemia, digitalis toxicity
• Side Effects: Bradycardia, arrhythmias, cardiac arrest, syncope
• Dosage (Adult): Base hospital order only. Calcium channel blocker overdose: 1 gm IV

Dextrose (D10W)

• Class: Carbohydrate
• MOA: Rapid source of glucose for cellular metabolism.
• Indications: Hypoglycemia
• Contraindications: Hyperglycemia
• Side Effects: Hyperglycemia, tissue necrosis
• Dosage (Adult): Dextrose 10%/250ml (25gm) IV/IO bolus
• Pediatric: Dextrose 10%/250ml (25gm) 0.5gm/kg (5ml/kg) IV/IO for neonates (<4 weeks) or pediatric patients (>4 weeks) with blood glucose <60mg/dL.

Diphenhydramine (Benadryl)

• Class: Antihistamine
• MOA: Blocks H1 receptors, preventing histamine release
• Indications: Allergic reactions, anaphylaxis
• Contraindications: Hypersensitivity
• Side Effects: Fatigue, headache, sedation, sleepiness, dizziness
• Dosage (Adult): 50mg IM or 25mg IV/IO slowly
• Pediatric: 2mg/kg IM or 1mg/kg IV/IO slowly, not exceeding adult dose.

Epinephrine (Epi, Adrenaline)

• Class: Sympathomimetic, endogenous catecholamine
• MOA: Alpha and beta adrenergic receptor agonist; vasoconstricts, increases heart rate, contractility, potentially initiates electrical activity in asystole and converts fine V-fib to coarse V-fib. Bronchodilator in anaphylaxis
• Indications: Pulseless electrical activity (PEA), asystole, anaphylaxis, bronchospasm
• Contraindications: (Generally none for cardiac arrest; caution with patients over 40 with CAD or HTN)
• Side Effects: Increased heart rate, hypertension, weakness, dizziness, syncope
• Dosage (Adult): Cardiac arrest/Asystole/PEA: 1mg IV/IO (1:10,000). Repeat after 2 minute cycle of CPR. Severe allergic reaction: 0.1 mg IVP/IO (1:10,000), repeat every 5 minutes up to 0.5mg. Bronchospasm/Anaphylaxis: 0.3mg IM (1:1000). May repeat after 15 minutes.
• Pediatric: Dosage scaled by weight

Fentanyl (Duragesic, Sublimaze)

• Class: Opioid analgesic, synthetic narcotic
• MOA: Binds to opioid receptors, blocking pain signals
• Indications: Isolated extremity trauma, burns, chest pain, cardioversion, pacing
• Contraindications: Allergy to fentanyl or other opioids, caution with pregnancy.
• Side Effects: Respiratory depression, bradycardia, dizziness, nausea, vomiting
• Dosage (Adult): For isolated extremity trauma, burns: 50mcg IV/IO over 1 minute, 100mcg IN/IM. May repeat at reduced doses. For pacing, cardioversion: 50mcg IV/IO. May repeat at reduced doses.