ロピバカイン
ロピバカインは、神経ブロック、局所および硬膜外麻酔技術による鎮痛に使用される長時間作用型のアミド系局所麻酔薬です。ブピバカインと比較して心毒性が低く、運動神経よりも感覚神経に対する選択性が高いため、運動神経ブロックの程度が軽減されます。難治性の重篤な不整脈を引き起こすリスクがあるため、静脈内投与は絶対に避けてください。
作用機序: Ropivacaine produces local anesthesia through the **reversible blockade of voltage-gated sodium channels** in nerve fibers. By binding to the intracellular portion of sodium channels, it prevents sodium influx → inhibits depolarization → prevents the generation and conduction of action potentials along the nerve fiber. Its higher lipid solubility allows it to preferentially block A-delta and C fibers (sensory/pain) over A-alpha fibers (motor).
動物種別の用量
- Analgesia (perineural, epidural, or intrapleural) · Up to 4 mg/kg · Perineural/Epidural/Intrapleural · q8h · Lower doses should be used when systemic absorption is likely to be high (e.g., intrapleural). Can be diluted with normal saline for wider distribution.
- Analgesia · Maximum 2 mg/kg · Perineural/Epidural/Intrapleural · The toxic dose has not been established in cats; it is recommended not to exceed 2 mg/kg.
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
- Intravenous (IV) administration
- Intravenous regional anaesthesia (Bier block)
有害事象
- Cardiac arrhythmias (if injected intravascularly)
- Systemic toxicity (CNS excitation followed by depression, seizures)
- Motor blockade (dose-dependent)
薬物相互作用
- Other local anaesthetics · Additive systemic toxicity; dose of ropivacaine should be reduced when used in combination. · major
- Adrenaline (Epinephrine) · Unlike some other local anesthetics, the addition of adrenaline does not appear to significantly alter the duration of the ropivacaine block. · null
モニタリング
- Heart rate and rhythm (ECG)
- Blood pressure
- Signs of CNS toxicity (twitching, tremors, seizures)
- Motor function recovery
過量投与
Overdosage or inadvertent intravascular injection can lead to severe systemic toxicity. * **Cardiovascular:** May precipitate severe cardiac arrhythmias that are highly refractory to standard treatments, hypotension, and cardiovascular collapse. * **CNS:** May cause excitation, tremors, and seizures, followed by CNS depression. * **Treatment:** Supportive care, oxygen therapy, seizure control (e.g., benzodiazepines), and potentially intravenous lipid emulsion (ILE) therapy for severe toxicity.
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。