What is the optimal lidocaine with epinephrine and saline mixture for a facelift in a 60‑kg woman?

Optimal Lidocaine-Epinephrine-Saline Mixture for Facelift in a 60 kg Woman

For a 60 kg woman undergoing facelift, use a diluted solution of 0.3-0.5% lidocaine with 1:100,000 to 1:200,000 epinephrine in normal saline, with a maximum total lidocaine dose of 420 mg (7 mg/kg), which translates to approximately 84-140 mL of solution depending on concentration chosen.

Dosing Calculations

Based on the American Academy of Dermatology guidelines, the maximum safe dose for lidocaine with epinephrine in adults is 7 mg/kg 1. For your 60 kg patient:

• Maximum lidocaine dose: 420 mg total
• If using 0.5% lidocaine (5 mg/mL): maximum 84 mL
• If using 0.3% lidocaine (3 mg/mL): maximum 140 mL

Recommended Mixture Formulation

The highest quality evidence for facelift procedures specifically comes from a 2007 pharmacokinetic study that used 0.33% lidocaine with 1:600,000 epinephrine at doses up to 21.6 mg/kg (3.1 times the traditional maximum) and demonstrated peak plasma levels 72% below toxic thresholds 2. However, I recommend staying within guideline-recommended limits of 7 mg/kg 1, 3 for safety in routine practice, as the guidelines carry stronger regulatory weight.

Practical Recipe Options:

Option 1 (More concentrated, smaller volume):

• 1% lidocaine with 1:100,000 epinephrine: 42 mL
• Normal saline: 42 mL
• Final concentration: 0.5% lidocaine, 1:200,000 epinephrine
• Total volume: 84 mL

Option 2 (More dilute, larger volume for better tissue expansion):

• 1% lidocaine with 1:100,000 epinephrine: 42 mL
• Normal saline: 98 mL
• Final concentration: 0.3% lidocaine, 1:333,000 epinephrine
• Total volume: 140 mL

Epinephrine Concentration Considerations

Research demonstrates that epinephrine concentrations between 1:50,000 and 1:400,000 provide equivalent vasoconstriction 4. More dilute solutions (beyond 1:400,000) have delayed onset and shortened duration 4. For facial surgery specifically, vasoconstriction lasts approximately 60 minutes with 1:100,000 to 1:200,000 concentrations 5.

Optional pH Buffering (Reduces Injection Pain)

While not essential for efficacy, adding sodium bicarbonate significantly reduces injection pain. The evidence shows:

• 3:1 ratio (lidocaine:bicarbonate) is less painful than 9:1 6
• For a 9:1 ratio: Add 4.2-4.7 mL of 8.4% sodium bicarbonate to 42 mL of lidocaine-epinephrine solution
• This raises pH from ~4.1 to 7.1-7.7 5

However, one study found that dilution with normal saline alone (1:10 ratio) was actually less painful than bicarbonate buffering 7, suggesting the dilution itself may be more important than pH adjustment.

Safety Measures to Prevent Toxicity

The FDA label and guidelines emphasize 3, 1:

• Aspirate before each injection to avoid intravascular administration
• Use incremental injections rather than rapid bolus
• Inject slowly over at least 20 minutes for the full volume
• Monitor continuously for early signs of toxicity (circumoral numbness, metallic taste, tinnitus, confusion)
• Wait at least 90 minutes before administering additional doses if needed

Timing Considerations

• Onset of maximum vasoconstriction: 1.3-26 minutes depending on concentration 5
• Duration of anesthesia: 112-480 minutes depending on concentration 5
• Peak plasma lidocaine levels: Occur at approximately 9 hours post-infiltration with dilute solutions 2

Critical Caveats

1. The 7 mg/kg limit is based on expert opinion (Level III evidence) 1, not high-quality trials. Research in facelift procedures has safely used up to 21.6 mg/kg 2, but I recommend adhering to guideline limits unless you have extensive experience and appropriate monitoring.

2. Avoid using these solutions for intra-articular injection - there are reports of chondrolysis 3.

3. For elderly or patients with cardiac/liver disease, reduce the dose 3.

4. Epinephrine provides cardioprotection through antiarrhythmic effects when used with general anesthesia 4, making it preferable to plain lidocaine even under general anesthesia.