Vecuronium Bromide is used as an adjunct to general anaesthesia to assist endotracheal intubation and to ensure skeletal muscle relaxation during surgical procedures or mechanical ventilation.

Vecuronium Bromide is supplied as a lyophilized powder for injection. It belongs to the group of non-depolarizing neuromuscular blocking agents. It works by competitively binding to acetylcholine at nicotinic receptors located at the motor end-plate of skeletal muscle, thereby inhibiting nerve impulse transmission to the muscle.

The recommended initial dose of Vecuronium is 0.08 to 0.10 mg/kg body weight given as an I.V. bolus injection. This dose can be expected to produce good or excellent non-emergency intubation conditions in 2.5 to 3.0 minutes after injection. In caesarean section and neonatal surgery the dose should not exceed 0.1 mg/kg. Like other neuromuscular blocking agents, Vecuronium Bromide should only be administered by, or under supervision of, experienced clinicians who are familiar with the action and use of these agents; the dosage of Vecuronium Bromide should be individualized in each patient. Consequently, adjustments with Vecuronium Bromide should be made by administering smaller maintenance doses at less frequent intervals or by using lower infusion rates of Vecuronium Bromide during long lasting procedures (longer than 1 hour) under inhalational anaesthesia. In adult patients the following dosage recommendations may serve as a general guideline for tracheal intubation and muscle relaxation for short to long lasting surgical procedures.

Tracheal intubation: The standard intubating dose during routine anaesthesia is 0.08 to 0.1 mg Vecuronium Bromide per kg body weight, after which adequate intubation conditions are established within 90 to 120 seconds in nearly all patients.

Dosages of Vecuronium Bromide for surgical: procedures after intubation with suxamethonium: If suxamethonium is used for intubation, the administration of Vecuronium should be delayed until the patient has clinically recovered from the neuromuscular block induced by suxamethonium. Recommended dose is 0.03 to 0.05 mg Vecuronium Bromide per kg body weight.

Maintenance dosing: The recommended maintenance dose is 0.02 to 0.03 mg Vecuronium Bromide per kg body weight. These maintenance doses should best be given when twitch height has recovered to 25% of control twitch height.

Dose requirements for administration of Vecuronium Bromide by continuous infusion: If Vecuronium is administered by continuous infusion, it is recommended to give a loading dose (0.08 to 0.1 mg Vecuronium Bromide per kg body weight) first and, when neuromuscular block starts to recover, to start administration of Vecuronium by infusion. The infusion rate should be adjusted to maintain twitch response at 10% of control twitch height or to maintain 1 to 2 responses to train of four stimulation. In adults, the infusion rate required to maintain neuromuscular block at this level, ranges from 0.8 to 1.4 µg Vecuronium Bromide/kg/min. Repeat monitoring of neuromuscular block is recommended since infusion rate requirements vary from patient to patient and with the anaesthetic method used.

Dosing in elderly patients: The same intubation and maintenance doses as for younger adults (0.08-0.1 mg/kg and 0.02-0.03 mg/kg, respectively) can be used. Onset time in elderly is similar to younger adults.

Dosing in paediatric patients: Neonate (up to 4 weeks) and children up to 4 months: initial test dose 0.01 to 0.02 mg/kg then incremental doses until 10% to 95% depression of twitch response is achieved is recommended. In neonatal surgery the dose should not exceed 0.1 mg/kg. Children over 5 months to 10 years: 0.08-0.1 mg/kg. Children under 12 months, onset more rapid and high intubation dose may not be required; maintenance 0.02-0.03 mg/kg adjusted according to response. Since the duration of action is shorter in children, maintenance doses are required more frequently.

Dosing in overweight and obese patients: When used in overweight or obese patients doses should be reduced taking into account an ideal body weight. Initial doses ranging from 0.15 mg up to 0.30 mg Vecuronium Bromide per kg body weight have been administered during surgery both under halothane and neurolept anaesthesia.

Administration

Vecuronium Bromide should be administered following reconstitution. VencurTM is administered intravenously either as a bolus injection or as a continuous infusion. Reconstitution: Alternatively, in order to obtain a solution with a lower concentration, Vecuronium Bromide 10 mg may be reconstituted with a volume up to 10 ml respectively of the following infusion fluids:

• 5% glucose IV solution
• 0.9% sodium chloride IV solution
• Lactated Ringer's solution
• Lactated Ringer's and 5% glucose IV solution
• Glucose 5% and 0.9% sodium chloride IV solution

Succinylcholine: Prior administration of succinylcholine may increase both the intensity and duration of the neuromuscular blocking action of Vecuronium. When succinylcholine is given first, Vecuronium should only be administered after the effects of succinylcholine begin to subside. If succinylcholine is used for intubation, an initial dose of 0.04–0.06 mg/kg of vecuronium can be given to achieve complete neuromuscular blockade, typically lasting 25–30 minutes. Other non-depolarizing neuromuscular blocking agents such as pancuronium, d-tubocurarine, metocurine, and gallamine act similarly to Vecuronium, and concurrent use may result in additive effects.

Inhalation Anesthetics: Volatile inhalational anesthetics including enflurane, isoflurane, and halothane can potentiate the neuromuscular blocking effect of Vecuronium.

Antibiotics: High doses of certain antibiotics administered parenterally or intraperitoneally may enhance or independently cause neuromuscular blockade. Antibiotics known to be associated with varying degrees of paralysis include aminoglycosides (e.g., neomycin, streptomycin, kanamycin, gentamicin, dihydrostreptomycin), tetracyclines, bacitracin, polymyxin B, colistin, and sodium colistimethate. When these or newly introduced antibiotics are used together with vecuronium during surgery, prolonged neuromuscular blockade may occur.

Other: Administration of quinidine during recovery from other muscle relaxants has been associated with recurrent paralysis, which may also occur with vecuronium. Neuromuscular blockade by vecuronium may be reduced by alkalosis and enhanced by acidosis, as observed in animal studies. Electrolyte imbalances and related conditions such as adrenal cortical insufficiency can modify neuromuscular blockade, leading to either increased or decreased effects. Magnesium salts used in the treatment of pregnancy-related toxemia may further enhance neuromuscular blockade.

Vecuronium is contraindicated in patients with known hypersensitivity to vecuronium, bromide ions, or any of its components.

Vecuronium Bromide is a non-depolarizing muscle relaxant with an intermediate duration of action. It generally does not cause histamine release and has minimal cardiovascular effects. Common adverse effects of this class include skin flushing, hypotension, tachycardia, bronchospasm, and rarely, anaphylactoid reactions. Prolonged use in intensive care settings has been associated with acute myopathy.

There is insufficient evidence regarding the use of Vecuronium during pregnancy in both animals and humans to determine potential risks to the fetus. It should be used during pregnancy only if the potential benefit justifies the possible risk. Data on its use during lactation are also lacking; therefore, it should be administered to breastfeeding women only when clearly necessary.

Caesarean section: Clinical studies using doses up to 0.1 mg/kg have demonstrated that Vecuronium is safe for use during caesarean section. The dose should not exceed 0.1 mg/kg. Studies have shown no adverse effects on Apgar score, fetal muscle tone, or cardiorespiratory adaptation. Minimal placental transfer has been observed, with no significant clinical effects on the newborn.

Cross-allergy among neuromuscular blocking agents has been reported; therefore, caution is necessary in patients with known hypersensitivity. The duration of action may be prolonged in patients with myasthenia gravis and in hypothermic conditions, requiring dose reduction. Non-depolarizing muscle relaxants should be used cautiously in patients with other neuromuscular disorders and in those with fluid or electrolyte imbalance, as responses may vary. Burn patients may develop resistance and require higher doses, while reduced plasma cholinesterase activity in such patients necessitates careful dose adjustment for certain agents.

General: Vecuronium should be administered in carefully titrated doses by or under the supervision of experienced clinicians familiar with its pharmacological effects and potential complications. It must not be used unless facilities for intubation, artificial ventilation, oxygen support, and reversal agents are readily available. The clinician should be prepared to manage or support respiration. Monitoring with a peripheral nerve stimulator is recommended to assess drug response, need for additional dosing, and adequacy of recovery or reversal.

Intensive Care Unit: To minimize the risk of prolonged neuromuscular blockade and associated complications during long-term use in ICU settings, Vecuronium or similar agents should be administered with careful dose adjustment under expert supervision, along with appropriate neuromuscular monitoring techniques.

Neuromuscular Disease: Patients with myasthenia gravis or related syndromes may exhibit heightened sensitivity to Vecuronium, even at low doses. In such cases, use of a peripheral nerve stimulator and administration of a small test dose can help determine appropriate dosing.

In case of overdose with prolonged neuromuscular blockade, ventilatory support and sedation should be maintained. Once spontaneous recovery begins, an acetylcholinesterase inhibitor (such as neostigmine, edrophonium, or pyridostigmine) may be administered in appropriate doses. If reversal is inadequate, assisted ventilation must continue until normal respiration returns. Repeated doses of reversal agents should be used cautiously, as they may pose risks.

Non-depolarizing muscle relaxants

Store in a cool, dry place. Protect from light. Keep out of reach of children.