Local Anaesthetic — Superdilute Tumescent Infiltration Pregnancy: Not applicable — cosmetic liposuction contraindicated in pregnancy.

Lidocaine Tumescent Solution (Liposuction/Infiltration)

Brand names: Klein's Solution — Compounded; Lidocaine + Adrenaline + Sodium Bicarbonate in Normal Saline

Adult dose

Dose: Super-wet technique: 1:1 infiltrate to aspirate (1 mL per 1 mL planned lipoaspirate). Tumescent: 2–3 mL per 1 mL planned aspirate. Standard Klein's solution: lidocaine 500–1000 mg/L saline (50–100 mg/100 mL) + adrenaline 1:1,000,000 + sodium bicarbonate 10 mEq/L. Dose: up to 55 mg/kg lidocaine tumescent (well above standard 7 mg/kg — pharmacokinetically validated).

Route: Subcutaneous infiltration via blunt cannula

Frequency: Single intraoperative infiltration session

Max: 35–55 mg/kg lidocaine (tumescent protocol — validated pharmacokinetic studies; NOT the standard 3–7 mg/kg limit which applies to non-tumescent use)

Tumescent anaesthesia allows safe mega-doses of lidocaine because: (1) superdilute vasoconstrictor dramatically slows absorption; (2) large subcutaneous volume creates slow-release depot; (3) peak plasma levels (Cmax) are low and delayed (12–14h). Pioneered by Klein 1990 — revolutionised liposuction allowing totally awake procedures.

Paediatric dose

Route:

Not applicable — liposuction not performed in paediatrics.

Dose adjustments

Renal

Reduce dose in severe renal failure — delayed lidocaine clearance; extended monitoring required.

Hepatic

Reduce dose significantly in hepatic impairment — lidocaine metabolised by CYP1A2/CYP3A4; accumulation risk. Max 35 mg/kg.

Clinical pearls

Klein's landmark paper (1990): Jeffrey Klein's original tumescent technique demonstrated that subcutaneous infiltration with very dilute lidocaine+epinephrine in normal saline — up to 55 mg/kg — was safe for liposuction. Pharmacokinetic studies showed peak lidocaine levels well below toxic threshold despite doses far exceeding the 3 mg/kg standard limit; the tumescent compartment acts as a slow-release depot
Post-operative monitoring: patients discharged same day must be monitored for at least 8 hours post-procedure and counselled to return immediately if symptoms of lidocaine toxicity develop (12–14 hour peak). Ideally, large-volume tumescent procedures (>5 L aspirate) are managed with overnight admission
Intralipid rescue for lidocaine toxicity (AAGBI/ACMT Guidelines): Intralipid 20% 1.5 mL/kg IV bolus, then 15 mL/kg/hour for 30 minutes — 'lipid sink' extracts lidocaine from cardiac tissue and redistributes to lipid phase; available in all anaesthetic areas; if patient collapses, give Intralipid before attempting resuscitation

Contraindications

Known lidocaine allergy
Concurrent antiarrhythmic drugs (class IB — mexiletine, tocainide — additive cardiac toxicity)
General anaesthesia without careful monitoring (sedation dramatically lowers toxic dose threshold; monitor continuously)
Hepatic failure (accumulation — reduce dose)

Side effects

Lidocaine systemic toxicity (delayed — peak 12–14h post-infiltration): tinnitus, perioral numbness, metallic taste, seizures, cardiac arrhythmias if excessive dose
Haematoma (fluid redistribution post-procedure)
Contour irregularities
Prolonged oedema (weeks to months)
Parasthesias at infiltration sites

Interactions

CYP3A4 inhibitors (ketoconazole, erythromycin, clarithromycin — increase lidocaine plasma levels; increase toxicity risk with tumescent doses)
Beta-blockers and antiarrhythmics (cardiac conduction effects — additive)
Oral antiarrhythmics class IB (mexiletine — additive CNS and cardiac toxicity — avoid)

Monitoring

Vital signs and ECG during infiltration
Continuous monitoring for minimum 8 hours post-procedure (lidocaine toxicity peak at 12–14h)
Total lidocaine dose calculation (document weight-based dose)
Signs of systemic toxicity: tinnitus, metallic taste, visual disturbance, agitation, confusion

Reference: BNFc; BNF 90; Klein JA. J Am Acad Dermatol 1990 (original tumescent paper); AAGBI Intralipid Guidance; ASPS Guidelines on Liposuction Safety; Ostad et al. Dermatol Surg 1996 (pharmacokinetics). Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators