パンクロニウム臭化物
パンクロニウム臭化物は、主に全身麻酔の補助として使用される**非脱分極性神経筋遮断薬**です。**気管挿管**、**人工呼吸**、および各種外科手術を容易にするための骨格筋弛緩を提供します。 > **重要な臨床的注意**：パンクロニウムには**鎮痛、鎮静、または健忘作用は一切ありません**。意識がある状態で麻痺する恐怖を防ぐため、使用前および使用中は患者に適切な鎮静と麻酔を行う必要があります。 * 長時間作用型のアミノステロイド系筋弛緩薬です。 * 他の薬剤と比較して作用時間が比較的長く（用量により30〜45分）、腎排泄に大きく依存します。 * d-ツボクラリンの5倍の効力があり、ベクロニウムの約3分の1の効力があると考えられています（ただし、動物では同等の効力があるとする文献もあります）。
作用機序: Pancuronium acts as a competitive antagonist at the **nicotinic acetylcholine receptors (nAChRs)** located at the **neuromuscular junction (motor endplate)**. * Pancuronium competitively binds to **nAChRs** → prevents **acetylcholine (ACh)** from binding → inhibits depolarization of the muscle fiber membrane → results in flaccid skeletal muscle paralysis. * **Cardiovascular Effects**: Unlike some other neuromuscular blockers, pancuronium has slight vagolytic (anticholinergic) activity at postganglionic **muscarinic receptors** in the heart → leads to slight increases in heart rate and blood pressure. * It rarely causes histamine release compared to older agents like d-tubocurarine.
動物種別の用量
- General muscle relaxation · 0.044-0.11 mg/kg IV · IV · as needed · higher dose used initially; lower doses required if repeated doses are necessary
- Neuromuscular blockade during anaesthesia · 0.025-0.075 mg/kg initially; repeat doses at increments of 0.01 mg/kg · IV · as needed · Duration of action >45 min · Initially use a higher dose. Repeated doses may be cumulative and lead to difficulty in antagonism.
- Muscle relaxation · 0.1 mg/kg IV · IV · as needed · Dose for rabbits
- As a paralytic during mechanical ventilation · 0.05-0.1 mg/kg IV · IV · lasts about an hour · must give sedation as well
- General muscle relaxation · 0.044-0.11 mg/kg IV · IV · as needed · higher dose used initially; lower doses required if repeated doses are necessary
- Anesthesia maintenance adjunct (when inhalational agents result in severe hypotension) · 0.02-0.04 mg/kg IV · IV · provides 30-45 minutes of muscle relaxation · Used when IV/regional techniques are inadequate to prevent spontaneous movement
- Neuromuscular blockade during anaesthesia · 0.025-0.075 mg/kg initially; repeat doses at increments of 0.01 mg/kg · IV · as needed · Duration of action >45 min · Initially use a higher dose. Repeated doses may be cumulative and lead to difficulty in antagonism.
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
禁忌
- Known hypersensitivity to pancuronium or bromides
- Myasthenia gravis (extreme caution or contraindicated)
- Conscious or inadequately anaesthetized animals
- Lack of positive pressure ventilation facilities
- Lack of monitoring equipment (nerve stimulator)
有害事象
- Slight elevations in cardiac rate and blood pressure
- Hypersalivation (if not pretreated with an anticholinergic agent)
- Prolonged or profound muscular weakness
- Respiratory depression
- Histamine release with resultant hypersensitivity reaction (Very Rare)
- Tachycardia (due to vagolytic effect)
- Prolonged neuromuscular blockade
- Mild hypertension
薬物相互作用
- Azathioprine · May reverse pancuronium's neuromuscular blocking effects
- Aminoglycosides (e.g., gentamicin) · May enhance the neuromuscular blocking activity of pancuronium
- Calcium (IV) · May reverse the effects of nondepolarizing neuromuscular blocking agents
- Lincosamides (e.g., clindamycin) · May enhance the neuromuscular blocking activity of pancuronium
- Magnesium sulfate or HCl · May enhance the neuromuscular blocking activity of pancuronium
- Quinidine · May enhance the neuromuscular blocking activity of pancuronium
- Succinylcholine · May speed the onset of action and enhance the neuromuscular blocking actions of pancuronium. Do not give pancuronium until succinylcholine effects have subsided.
- Theophylline · May inhibit or reverse the neuromuscular blocking action of pancuronium and possibly induce arrhythmias
- Tricyclic Antidepressants (e.g., clomipramine, amitriptyline) · Increased risk for cardiac arrhythmias when used with halothane anesthesia
- Volatile anaesthetics · Prolonged neuromuscular blockade · moderate
- Aminoglycosides · Prolonged neuromuscular blockade · major
- Clindamycin · Prolonged neuromuscular blockade · moderate
モニタリング
- Level of neuromuscular blockade (via peripheral nerve stimulation)
- Cardiac rate and rhythm
- Blood pressure
- Adequacy of ventilation and oxygenation
- Peripheral nerve stimulation (e.g., Train-of-Four)
- Heart rate and rhythm
- Respiratory rate, effort, and ventilator parameters (EtCO2, SpO2)
- Body temperature
- Acid-base status
- Serum potassium levels
過量投与
Overdosage increases the risk of **hypotension**, **histamine release**, and **prolonged duration of muscle blockade**. **Treatment:** * **Conservative Support**: Maintain mechanical ventilation, oxygen therapy, and IV fluids until spontaneous breathing returns. * **Pharmacologic Reversal**: Blockade may be reversed by administering an **anticholinesterase agent** (e.g., edrophonium, physostigmine, or neostigmine). * **CRITICAL**: An **anticholinergic** (atropine or glycopyrrolate) MUST be administered prior to or alongside the reversal agent to prevent severe bradycardia and muscarinic side effects. * *Suggested Reversal Protocol*: **Neostigmine** 0.06 mg/kg IV *after* **Atropine** 0.02 mg/kg IV.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。