atropine + fentanyl + mivacurium

The combination of atropine, fentanyl, and mivacurium is a premedication regimen used primarily for neonatal and pediatric endotracheal intubation. This combination provides comprehensive preparation for intubation by addressing multiple physiological aspects of the procedure. ## Pharmacological Components **Atropine** is an anticholinergic agent that blocks muscarinic receptors, particularly at the M2 receptors in the sinoatrial and atrioventricular nodes. This action prevents bradycardia during intubation and reduces secretions that could complicate the procedure[3][4]. **Fentanyl** is a potent synthetic opioid analgesic that provides rapid analgesia and sedation. It's highly lipophilic, crosses the blood-brain barrier quickly, and offers greater analgesic potency with faster onset than morphine. During intubation, it helps block stress responses and prevents increases in pulmonary vascular resistance[8]. **Mivacurium** is a short-acting, non-depolarizing neuromuscular blocking agent that facilitates intubation by causing skeletal muscle relaxation. It works by competitively binding to cholinergic receptors on the motor end-plate, antagonizing acetylcholine's action. This creates optimal intubation conditions while having a relatively brief duration of action (5-15 minutes)[5][6]. ## Clinical Use and Efficacy This combination has been studied in several clinical trials and has shown significant benefits for endotracheal intubation, particularly in neonates and infants: - Reduces the time and number of attempts needed for successful intubation[1][5] - Decreases the incidence of severe oxygen desaturation during the procedure[1][2] - Provides stable intubation conditions with rapid onset (1-3 minutes)[5][7] - Offers a relatively short duration of action, particularly for mivacurium (5-15 minutes)[5][7] ## Dosing Protocol A typical protocol for this combination includes: - Atropine: 20 μg/kg intravenously[5][7] - Fentanyl: 3-5 μg/kg intravenously (administered slowly)[5][7][8] - Mivacurium: 200 μg/kg administered over 15-30 seconds[5] The medications are typically administered in sequence: atropine first, followed by mivacurium, and then fentanyl[5]. ## Considerations and Precautions While effective, this combination requires careful monitoring for potential adverse effects: - Hypotension may occur, though it often resolves spontaneously[2] - Respiratory events including thoracic rigidity (a known effect of synthetic opioids)[2] - Atropine should be used with caution in patients with glaucoma, pyloric stenosis, or prostatic hypertrophy[3] - The combination may interact with other medications, particularly those affecting cholinergic transmission[4] This premedication regimen is primarily indicated for non-emergent intubations in neonatal intensive care units and pediatric settings[1][7].