Vecuronium is a medication primarily used as a muscle relaxant during anesthesia and in the intensive care unit (ICU). It belongs to the class of drugs known as nondepolarizing neuromuscular blocking agents, which work by blocking the action of acetylcholine at the neuromuscular junction, leading to muscle relaxation.

Vecuronium prevents acetylcholine from attaching to the motor endplate receptors, which prevents depolarization.

In addition to general anaesthesia, it is used to facilitate endotracheal intubation and to relax skeletal muscles during surgery or mechanical breathing in sedated ICU patients.

• The neuromuscular blockade does not help in pain control, sedation, or amnestic effects.
• Adequate analgesia and sedative medications should be given before and during the administration of neuromuscular blockade to help in achieving deep sedation.

Label Use of Vecuronium in Adults includes:

• Shivering due to therapeutic hypothermia after cardiac arrest
• Acute respiratory distress syndrome

"It is one of the WHO's lists of essential medicines"

Vecuronium Dose in Adult

• Vecuronium is a medicine used during surgery or in intensive care to make muscles relax.
• It's given through a vein.
• This helps with procedures like putting a breathing tube in or using a ventilator.
• It's important to give the right amount because too much can cause problems like breathing trouble.
• Make sure the patient isn't feeling pain and is sleepy enough before giving Vecuronium.

Vecuronium dosage for administering neuromuscular blockade treatment before endotracheal intubation, mechanical ventilation, or surgery:

Tracheal intubation:

• Give an initial dose of 0.08 to 0.1 mg/kg through the vein.
• If you use succinylcholine for intubation, you can give a lower initial dose of 0.04 to 0.06 mg/kg with inhalation anesthesia or 0.05 to 0.06 mg/kg with balanced anesthesia.

Obesity:

• For obese patients (≥130% of ideal body weight), you can use ideal body weight for dosing.
• However, it might take a bit longer to start working.

Pretreatment/priming:

• Give 10% of the intubating dose 3 to 5 minutes before the main dose.

Maintenance during surgery:

• After the muscles start working again, you can give intermittent doses of 0.01 to 0.015 mg/kg or a continuous infusion of 0.8 to 1.2 mcg/kg/minute (equivalent to 0.048 to 0.072 mg/kg/hour).
• If you're using an inhaled anesthetic, stick to the lower end of the dose range and adjust the timing based on monitoring with a nerve stimulator.

Vecuronium off-label dosage in the intensive care unit paralysis:

Initial bolus dose:

• Administer 0.08 to 0.1 mg/kg through the vein, followed by a continuous IV infusion of 0.8 to 1.7 mcg/kg/minute (equivalent to 0.048 to 0.102 mg/kg/hour).
• Monitor the depth of muscle paralysis every 1 to 2 hours at first until the dose stabilizes, then every 8 to 12 hours.

Usual maintenance infusion dose range:

• Typically, maintain an infusion rate of 0.8 to 1.2 mcg/kg/minute (0.048 to 0.072 mg/kg/hour).

Dosage adjustment:

• Adjust the infusion rate by increments of 0.3 mcg/kg/minute (or 0.018 mg/kg/hour) or by reducing the previous dose by 50% based on the desired clinical response and, if possible, peripheral nerve stimulation response.

Discontinuation:

• If muscle function doesn't return, stop the infusion.

Note: Try to minimize the depth and duration of paralysis. Stopping the infusion daily until necessary can reduce complications. For intermittent dosing, give 0.1 to 0.2 mg/kg per dose, which can be repeated as needed. For shivering due to therapeutic hypothermia, you may use 8 to 12 mg, repeating as necessary for control.

Vecuronium Dose in Children

• The amount of Vecuronium given depends on how the patient responds, and it can vary between people.
• For obese patients, the dose is calculated based on their ideal body weight.

Vecuronium Dose for Paralysis (as a skeletal muscle relaxant):

• Infants (>7 weeks), Children, and Adolescents:
  • IV: Give 0.08 to 0.1 mg/kg; if intubation is done with succinylcholine, the initial dose can be lowered to 0.04 to 0.06 mg/kg with inhalation anesthesia or 0.05 to 0.06 mg/kg with balanced anesthesia. Children aged 1 to 10 years might need slightly higher initial doses and more frequent supplementation.
• Alternate Dosing (for Infants and Children):
  • IV: Provide 0.08 to 0.1 mg/kg per dose; repeat if necessary.
  • Continuous IV infusion: Administer 0.8 to 1.7 mcg/kg/minute (equivalent to 0.05 to 0.1 mg/kg/hour).
• Alternate Dosing (for Children and Adolescents):
  • IV: Same as infants' alternate dosing.
  • Continuous IV infusion: Offer 0.8 to 2.5 mcg/kg/minute (equivalent to 0.05 to 0.15 mg/kg/hour).

Pregnancy Risk Factor C

• Vecuronium is categorized as Pregnancy Risk Factor C, meaning its safety during pregnancy is uncertain as no animal studies have been conducted.
• The way Vecuronium moves through the body changes during pregnancy.
• It has been used in cesarean sections, and when measured, the amount found in the baby's umbilical vein at birth was around 11% of what was in the mother's blood.

Vecuronium use during breastfeeding:

• It's unclear whether Vecuronium is found in breast milk.
• The manufacturer advises caution when giving Vecuronium to breastfeeding women.

Vecuronium Dose in Renal disease:

• The manufacturer's label doesn't specify dosage adjustments for patients with renal impairment.
• However, individuals with renal issues usually don't have a significant lengthening of muscle relaxation time with Vecuronium.
• But in patients without kidneys (anephric), the effect might last longer.

Vecuronium Dose in Liver Disease:

• The manufacturer's instructions don't include dosage adjustments for liver disease.
• However, it may be necessary to reduce the dosage in patients with liver issues.

Side effects of Vecuronium:

• rash
• edema
• flushing
• Allergic reactions including hypotension, tachycardia, erythema, rash, and urticaria
• itching
• Bradycardia
• circulatory collapse

Contraindications to Vecuronium Include:

• If someone has had a hypersensitive reaction to Vecuronium or any part of its formula, they should not use it.
• While there's limited evidence of allergic reactions to neuromuscular blockers, like Vecuronium, due to similarities in structure or effects, there might be a chance of cross-sensitivity.

Warnings and precautions

Anaphylaxis

• Vecuronium use has been linked to severe anaphylactic reactions, some of which have been life-threatening or fatal.
• It's crucial to have emergency treatment, such as epinephrine 1 mg/mL, ready immediately when using Vecuronium.
• Caution is advised in patients with a history of anaphylactic reactions to other neuromuscular-blocking agents.

Paralysis for a prolonged period

• After using Vecuronium, some patients might take longer to regain normal muscle function, especially with prolonged use.
• Factors like corticosteroid usage or certain medical conditions can also contribute to this delayed recovery.

Burn injury:

• In burn patients with more than 20% of their body surface area affected, resistance to Vecuronium may develop.
• This resistance typically appears a few days after the injury and might last for several months even after the burns have healed.

Renal impairment

• In most cases, patients with kidney issues don't typically have a significant lengthening of muscle relaxation time with Vecuronium.
• However, in patients without kidneys (anephric), the effect might last longer.

Conditions that could lead to neuromuscular blockade (decreased parity)

• Several conditions can counteract the effects of neuromuscular blockade, leading to decreased paralysis.
• These include respiratory alkalosis, high levels of calcium in the blood (hypercalcemia), demyelinating lesions in the nervous system, peripheral neuropathies, denervation (loss of nerve supply to muscles), and muscle trauma.

Conditions that can increase neuromuscular blockade (increased parity):

• Certain conditions can enhance the effects of neuromuscular blockade, leading to increased paralysis.
• These include electrolyte imbalances such as severe hypocalcemia, severe hypokalemia, and hypermagnesemia.
• Neuromuscular diseases, metabolic acidosis, respiratory acidosis, Eaton-Lambert syndrome, and myasthenia gravis are also among the conditions that can potentiate neuromuscular blockade.

Hepatic impairment

• Be cautious when using Vecuronium in patients with liver problems, as it may take longer for the effects to wear off.

Respiratory disease

• Exercise caution when using Vecuronium in patients with pre-existing respiratory conditions.

Vecuronium: Drug Interaction

Monitor:

Monitoring in ICU:

• Vital Signs: Keep an eye on heart rate, blood pressure, and respiratory rate.
• Muscle Paralysis: Check for signs like spontaneous movement, ventilator asynchrony, and shivering. Consider using a peripheral nerve stimulator with train of four monitoring alongside clinical assessments.
• Preventing Prolonged Paralysis: In the ICU, watch out for extended paralysis and muscle weakness after stopping Vecuronium. Properly monitoring the level of muscle relaxation can help minimize these effects.

How to administer Vecuronium?

• IV Use Only: Vecuronium is meant for intravenous (IV) administration only. Avoid giving it intramuscularly (IM).
• Concentration: A concentration of 1 mg/mL can be given quickly through IV injection. It can also be used for IV infusion in patients who need restricted fluid intake.

Mechanism of action of Vecuronium:

• Vecuronium works by preventing acetylcholine, a neurotransmitter, from binding to receptors on the motor endplate, which stops the process of depolarization.

Onset of Action:

• Good Intubation Conditions: Typically achieved within 2.5 to 3 minutes.
• Maximum Neuromuscular Blockade: Typically reached within 3 to 5 minutes after administration.

Duration:

• Under Balanced Anesthesia: Time to recover to 25% of control ranges from 25 to 40 minutes. Recovery to 95% complete occurs approximately 45 to 65 minutes after the injection of the intubating dose. Hypothermia may prolong the duration of action.

Distribution:

• Volume of Distribution (V): Approximately 0.3 to 0.4 L/kg.

Protein Binding:

• Approximately 60% to 80%.

Metabolism:

• The active metabolite is 3-desacetyl vecuronium, but its activity compared to the parent drug is not specified.

Half-life, Elimination:

• Infants: Approximately 65 minutes.
• Children: Approximately 41 minutes.
• Healthy adult surgical patients and renal failure patients undergoing transplant surgery: Approximately 65 to 75 minutes.
• Late Pregnancy: Approximately 35 to 40 minutes.

Half-life, Distribution:

• In adults: Approximately 4 minutes.

Excretion:

• Primarily through feces (40% to 75%) and urine (30% as unchanged drug and metabolites). The rate of elimination is considerably reduced with hepatic dysfunction but not with renal dysfunction.

International Brands of Vecuronium:

• Curon
• Ecron
• Muscuvec
• Neovec
• Nodescron
• Nodescrón
• Nor Q
• Norcuron
• Survec
• Vecural
• Vecure
• Vecuron

Vecuronium bromide brands in Pakistan: