Carcinogenesis, Mutagenesis, Impairment of Fertility
Long-term studies in animals have not been performed to evaluate carcinogenic or mutagenic potential or impairment of fertility.
Pregnancy Category C: Animal reproduction studies have not been conducted with vecuronium. It is also not known whether vecuronium can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Vecuronium bromide should be given to a pregnant woman only if clearly needed.
Labor and Delivery
The use of vecuronium in patients undergoing cesarean section has been reported in the literature. Following tracheal intubation with succinylcholine, vecuronium dosages of 0.04 mg/kg (n=11) and 0.06 to 0.08 mg/kg (n=20) were administered. The umbilical venous plasma concentrations were 11% of maternal concentrations at delivery and mean neonate APGAR scores at 5 minutes were ≥ 9 in both reports. The action of neuromuscular blocking agents may be enhanced by magnesium salts administered for the management of toxemia of pregnancy.
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when vecuronium is administered to a nursing woman.
Infants under 1 year of age but older than 7 weeks also tested under halothane anesthesia, are moderately more sensitive to vecuronium on a mg/kg basis than adults and take about 1 1/2 times as long to recover. See Use in Pediatrics subsection of DOSAGE AND ADMINISTRATION for recommendations for use in pediatric patients 7 weeks to 16 years of age. The safety and effectiveness of vecuronium in pediatric patients less than 7 weeks of age have not been established.
The most frequent adverse reaction to nondepolarizing blocking agents as a class consists of an extension of the drug’s pharmacological action beyond the time period needed. This may vary from skeletal muscle weakness to profound and prolonged skeletal muscle paralysis resulting in respiration insufficiency or apnea.
Inadequate reversal of the neuromuscular blockade is possible with vecuronium as with all curariform drugs. These adverse reactions are managed by manual or mechanical ventilation until recovery is judged adequate. Little or no increase in intensity of blockade or duration of action of vecuronium is noted from the use of thiobarbiturates, narcotic analgesics, nitrous oxide, or droperidol. See OVERDOSAGE for discussion of other drugs used in anesthetic practice which also cause respiratory depression.
Prolonged to profound extensions of paralysis and/or muscle weakness as well as muscle atrophy have been reported after long-term use to support mechanical ventilation in the intensive care unit. (See PRECAUTIONS). The administration of vecuronium has been associated with rare instances of hypersensitivity reactions (bronchospasm, hypotension and/or tachycardia, sometimes associated with acute urticaria or erythema); (See also CLINICAL PHARMACOLOGY).
The possibility of iatrogenic overdosage can be minimized by carefully monitoring muscle twitch response to peripheral nerve stimulation.
Excessive doses of vecuronium produce enhanced pharmacological effects. Residual neuromuscular blockade beyond the time period needed may occur with vecuronium as with other neuromuscular blockers. This may be manifested by skeletal muscle weakness, decreased respiratory reserve, low tidal volume, or apnea. A peripheral nerve stimulator may be used to assess the degree of residual neuromuscular blockade from other causes of decreased respiratory reserve.
Respiratory depression may be due either wholly or in part to other drugs used during the conduct of general anesthesia such as narcotics, thiobarbiturates and other central nervous system depressants.
Under such circumstances the primary treatment is maintenance of a patent airway and manual or mechanical ventilation until complete recovery of normal respiration is assured. Pyridostigmine, neostigmine, or edrophonium, in conjunction with atropine or glycopyrrolate will usually antagonize the skeletal muscle relaxant action of vecuronium. Satisfactory reversal can be judged by adequacy of skeletal muscle tone and by adequacy of respiration. A peripheral nerve stimulator may also be used to monitor restoration of twitch height. Failure of prompt reversal (within 30 minutes) may occur in the presence of extreme debilitation, carcinomatosis, and with concomitant use of certain broad spectrum antibiotics, or anesthetic agents and other drugs which enhance neuromuscular blockade or cause respiratory depression of their own. Under such circumstances the management is the same as that of prolonged neuromuscular blockade. Ventilation must be supported by artificial means until the patient has resumed control of his respiration. Prior to the use of reversal agents, reference should be made to the specific package insert of the reversal agent.
The effects of hemodialysis and peritoneal dialysis on plasma levels of vecuronium and its metabolite are unknown.
Vecuronium bromide for injection is for intravenous use only.
This drug should be administered by or under the supervision of experienced clinicians familiar with the use of neuromuscular blocking agents. Dosage must be individualized in each case. The dosage information which follows is derived from studies based upon units of drug per unit of body weight and is intended to serve as a guide only, especially regarding enhancement of neuromuscular blockade of vecuronium by volatile anesthetics and by prior use of succinylcholine (See PRECAUTIONS: Drug Interactions). Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit.
To obtain maximum clinical benefits of vecuronium and to minimize the possibility of overdosage, the monitoring of muscle twitch response to peripheral nerve stimulation is advised.
The recommended initial dose of vecuronium bromide is 0.08 to 0.10 mg/kg (1.4 to 1.75 times the ED90 ) given as an intravenous bolus injection. This dose can be expected to produce good or excellent non-emergency intubation conditions in 2.5 to 3 minutes after injection. Under balanced anesthesia, clinically required neuromuscular blockade lasts approximately 25-30 minutes, with recovery to 25% of control achieved approximately 25 to 40 minutes after injection and recovery to 95% of control achieved approximately 45-65 minutes after injection. In the presence of potent inhalation anesthetics, the neuromuscular blocking effect of vecuronium is enhanced. If vecuronium is first administered more than 5 minutes after the start of inhalation agent or when steady state has been achieved, the initial vecuronium bromide dose may be reduced by approximately 15%, i.e., 0.060 to 0.085 mg/kg.
Prior administration of succinylcholine may enhance the neuromuscular blocking effect and duration of action of vecuronium. If intubation is performed using succinylcholine, a reduction of initial dose of vecuronium bromide to 0.04-0.06 mg/kg with inhalation anesthesia and 0.05-0.06 mg/kg with balanced anesthesia may be required.
During prolonged surgical procedures, maintenance doses of 0.010 to 0.015 mg/kg of vecuronium bromide are recommended; after the initial vecuronium injection, the first maintenance dose will generally be required within 25 to 40 minutes. However, clinical criteria should be used to determine the need for maintenance doses.
Since vecuronium lacks clinically important cumulative effects, subsequent maintenance doses, if required, may be administered at relatively regular intervals for each patient, ranging approximately from 12 to 15 minutes under balanced anesthesia, slightly longer under inhalation agents. (If less frequent administration is desired, higher maintenance doses may be administered.)
Should there be reason for the selection of larger doses in individual patients, initial doses ranging from 0.15 mg/kg up to 0.28 mg/kg have been administered during surgery under halothane anesthesia without ill effects to the cardiovascular system being noted as long as ventilation is properly maintained (See CLINICAL PHARMACOLOGY).
After an intubating dose of 80-100 mcg/kg, a continuous infusion of 1 mcg/kg/min can be initiated approximately 20-40 min later. Infusion of vecuronium bromide should be initiated only after early evidence of spontaneous recovery from the bolus dose. Long- term intravenous infusion to support mechanical ventilation in the intensive care unit has not been studied sufficiently to support dosage recommendations. (See PRECAUTIONS).
The infusion of vecuronium bromide should be individualized for each patient. The rate of administration should be adjusted according to the patient’s twitch response as determined by peripheral nerve stimulation. An initial rate of 1 mcg/kg/min is recommended, with the rate of the infusion adjusted thereafter to maintain a 90% suppression of twitch response. Average infusion rates may range from 0.8 to 1.2 mcg/kg/min.
Inhalation anesthetics, particularly enflurane and isoflurane may enhance the neuromuscular blocking action of nondepolarizing muscle relaxants. In the presence of steady-state concentrations of enflurane or isoflurane, it may be necessary to reduce the rate of infusion 25-60 percent, 45-60 min after the intubating dose. Under halothane anesthesia it may not be necessary to reduce the rate of infusion.
Spontaneous recovery and reversal of neuromuscular blockade following discontinuation of vecuronium infusion may be expected to proceed at rates comparable to that following a single bolus dose (See CLINICAL PHARMACOLOGY).
Infusion solutions of vecuronium bromide can be prepared by mixing vecuronium bromide with an appropriate infusion solution such as 5% Dextrose Injection, 0.9% Sodium Chloride Injection, Dextrose 5% and Sodium Chloride Injection, or Lactated Ringer’s Injection.
Unused portions of infusion solutions should be discarded.
Infusion rates of vecuronium bromide can be individualized for each patient using the following table:
|Drug Delivery Rate||Infusion Delivery Rate|
|0.1 mg/mL*||0.2 mg/mL**|
|* 10 mg of Vecuronium bromide in 100 mL solution|
|** 20 mg of Vecuronium bromide in 100 mL solution|
The following table is a guideline for mL/min delivery for a solution of 0.1 mg/mL (10 mg in 100 mL) with an infusion pump.
|Amount of Drug||Patient Weight–kg|
|NOTE: If a concentration of 0.2 mg/mL is used (20 mg in 100 mL), the rate should be decreased by one-half.|
Pediatric patients (10 to 16 years of age) have approximately the same dosage requirements (mg/kg) as adults and may be managed the same way. Younger pediatric patients (1 to 10 years of age) may require a slightly higher initial dose and may also require supplementation slightly more often than adults.
Infants under 1 year of age but older than 7 weeks are moderately more sensitive to vecuronium on a mg/kg basis than adults and take about 1 1/2 times as long to recover. See also subsection of PRECAUTIONS titled Pediatric Use. Information presently available does not permit recommendation on usage in pediatric patients less than 7 weeks of age (see PRECAUTIONS). There are insufficient data concerning continuous infusion of vecuronium in pediatric patients, therefore, no dosing recommendations can be made.
DrugInserts.com provides trustworthy package insert and label information about marketed drugs as submitted by manufacturers to the US Food and Drug Administration. Package information is not reviewed or updated separately by DrugInserts.com. Every individual package label entry contains a unique identifier which can be used to secure further details directly from the US National Institutes of Health and/or the FDA.