Atracurium
Atracurium is an intermediate-acting, non-depolarizing neuromuscular blocking agent used in veterinary anesthesia. It provides **neuromuscular blockade** to improve surgical access through muscle relaxation, facilitates positive pressure ventilation, and is particularly useful for intraocular surgery (e.g., to centralize the globe). It has an intermediate duration of action (15-35 minutes) and is non-cumulative due to its unique non-enzymatic degradation pathway (**Hofmann elimination**). Because its clearance is independent of hepatic and renal function, it is highly suitable for administration to animals with renal or hepatic disease. > **Clinical Pearl:** Atracurium does not provide any analgesic or sedative effects. It must strictly be used in fully anesthetized patients.
Mecanismo: Atracurium acts as a competitive antagonist at the neuromuscular junction. It inhibits the actions of **acetylcholine** → binds competitively to the **nicotinic acetylcholine receptors** on the post-junctional membrane of skeletal muscle → prevents acetylcholine from binding → prevents muscle cell depolarization → results in flaccid muscle paralysis.
Dosificación por especie
- Neuromuscular blockade during anaesthesia · 0.2-0.5 mg/kg initially, followed by increments of 0.2 mg/kg · IV · as needed · Intermediate duration (15-35 min) · Monitor with nerve stimulator
- Neuromuscular blockade during anaesthesia · 0.2-0.5 mg/kg initially, followed by increments of 0.2 mg/kg · IV · as needed · Intermediate duration (15-35 min) · Monitor with nerve stimulator
Las dosis son una referencia clínica para médicos veterinarios. Confirme siempre con la información vigente del producto y el paciente individual.
Vías de administración
Contraindicaciones
- Conscious or inadequately anesthetized animals
- Lack of positive pressure ventilation facilities
- Lack of trained personnel to monitor neuromuscular blockade
- Conscious animals (must NEVER be administered unless the animal is adequately anesthetized)
Efectos adversos
- Histamine release (especially with rapid IV injection)
- Bronchospasm
- Hypotension
- Tachycardia
- Histamine release (especially with rapid IV administration)
Interacciones farmacológicas
- Volatile anaesthetics · Prolonged neuromuscular blockade · major
- Aminoglycosides · Prolonged neuromuscular blockade · moderate
- Clindamycin · Prolonged neuromuscular blockade · moderate
- Lincomycin · Prolonged neuromuscular blockade · moderate
Monitoreo
- Neuromuscular function (using a peripheral nerve stimulator / Train-of-Four)
- Respiratory rate and effort (mechanical ventilation parameters)
- End-tidal CO2 (capnography)
- Oxygen saturation (pulse oximetry)
- Heart rate and rhythm (ECG)
- Blood pressure
- Core body temperature
- Neuromuscular function (using a peripheral nerve stimulator/Train-of-Four monitor)
- Respiratory rate, effort, and end-tidal CO2
- Heart rate and blood pressure
- Core body temperature (hypothermia prolongs effect)
- Acid-base status and potassium levels
Sobredosis
Overdosage results in **prolonged neuromuscular blockade** and respiratory paralysis. * **Management:** Requires continuous mechanical positive pressure ventilation until spontaneous recovery occurs. * **Reversal:** Pharmacological reversal agents (e.g., neostigmine or edrophonium) combined with an anticholinergic (e.g., atropine or glycopyrrolate to prevent severe bradycardia) should be administered once signs of spontaneous recovery begin (confirmed via nerve stimulator).
La referencia de fármacos de VetSheet está destinada a médicos veterinarios como apoyo a la decisión clínica; no sustituye el juicio profesional ni la información vigente del fabricante.