Bupivacaine

Source product: Bupivacaine 2.5 mg/ml Solution for Injection (UK SPC §4.2). Dose depends on the area anaesthetised, tissue vascularity, number of neuronal segments to be blocked, individual tolerance and technique; use the lowest dose that provides effective anaesthesia. Reduce these doses for young, elderly or debilitated patients. ADULT TABLE (conc / volume / dose): Surgical anaesthesia — lumbar epidural (surgery or Caesarean section) 5 mg/ml, 15–30 ml = 75–150 mg, onset 15–30 min, duration 2–3 h; thoracic epidural 2.5 mg/ml, 5–15 ml = 12.5–37.5 mg (onset 10–15 min, 1.5–2 h) or 5 mg/ml, 5–10 ml = 25–50 mg (2–3 h); caudal epidural block 2.5 mg/ml, 20–30 ml = 50–75 mg or 5 mg/ml, 20–30 ml = 100–150 mg; major nerve block (e.g. brachial plexus, femoral, sciatic) 5 mg/ml, 10–35 ml = 50–175 mg, duration 4–8 h; field block 2.5 mg/ml <60 ml = <150 mg, or 5 mg/ml ≤30 ml = ≤150 mg. Acute pain management — intra-articular block (e.g. single injection after knee arthroscopy) 2.5 mg/ml ≤40 ml = ≤100 mg; field block 2.5 mg/ml ≤60 ml = ≤150 mg. Epidural doses include the test dose. Dose for a major nerve block must be adjusted to site and patient status; interscalene and supraclavicular brachial plexus blocks may carry a higher frequency of serious adverse reactions. Bupivacaine is NOT approved for continuous intra-articular infusion (post-marketing reports of chondrolysis). ADMINISTRATION: aspirate repeatedly before and during administration to avoid intravascular injection; inject slowly or in incremental doses at a rate of 25–50 mg/min while observing vital functions and maintaining verbal contact; a preceding test dose of 3–5 ml bupivacaine containing adrenaline (epinephrine) is recommended before an epidural dose; stop the injection immediately if toxic symptoms occur. When prolonged blocks are used (continuous infusion or repeated bolus), consider the risk of reaching toxic plasma concentrations.

SPC states a RANGE, not a single figure: caudal, lumbar and thoracic epidural administration in children 1–12 years = 0.6–0.8 ml/kg of 2.5 mg/ml, equivalent to 1.5–2 mg/kg — dosePerKg deliberately left null so no single value is implied. Other stated paediatric figures: field block and peripheral nerve blocks (e.g. ilioinguinal–iliohypogastric) with 2.5 or 5 mg/ml = 0.5–2.0 mg/kg. Peritonsillar infiltration in children above 2 years: bupivacaine 2.5 mg/ml at 7.5–12.5 mg per tonsil. Ilioinguinal-iliohypogastric block in children aged 1 year or older: bupivacaine 2.5 mg/ml 0.1–0.5 ml/kg = 0.25–1.25 mg/kg; children aged 5 years or older have received bupivacaine 5 mg/ml at 1.25–2 mg/kg. Penile block: bupivacaine 5 mg/ml 0.2–0.5 ml/kg = 1–2.5 mg/kg. Paediatric regional anaesthetic procedures should be performed by qualified clinicians familiar with this population and technique; in children with a high body weight a gradual reduction of dose is often necessary, based on ideal body weight; thoracic epidural blocks need incremental dosing until the desired level is achieved. Safety and efficacy in children <1 year of age have not been established (only limited data). US labelling states administration in patients younger than 12 years is not recommended, and that continuous infusions in paediatric patients have been reported to result in high systemic levels and seizures. Verify against a children's formulary.