Local Anesthetic Administration Technique for Incisions
Yes, local anesthetic is injected directly into the incision site, including both the skin and subcutaneous tissue, and this is the standard, safe, and recommended approach for office-based dermatologic procedures. 1
Standard Infiltration Technique
Local infiltrative anesthesia is safe and recommended for office-based dermatologic procedures including biopsy, excision, wound closure, tissue rearrangement, skin grafting, and cauterization. 1 The anesthetic is administered by:
- Subcutaneous or intradermal infiltration directly at the planned incision site 1
- Injection through intact skin along the line of the planned incision 2
- Systematic extensive infiltration in various tissue planes under direct visualization before wound closure 3
Optimal Timing and Depth
Pre-incisional injection is preferable to post-procedure administration because it significantly reduces general anesthesia requirements and cumulative anesthetic exposure. 4 A pediatric study demonstrated a 21% reduction in sevoflurane dose when local anesthetic was given before incision versus after surgical release. 4
For enhanced analgesia, combined subcutaneous and deep infiltration (beneath the external oblique muscle layer) provides superior pain control compared to subcutaneous injection alone, with prolonged time to first analgesic requirement and lower pain scores in the first 8 postoperative hours. 5
Pain Reduction Strategies
Injecting from within an open wound (when applicable) causes significantly less pain than injection through intact skin. 6 In laceration repair, median pain scores were 14 mm for inside-the-wound injections versus 37 mm for intact skin injections (p < 0.0001). 6
Adding sodium bicarbonate to lidocaine with epinephrine is strongly recommended to decrease the pain of subcutaneous or intradermal infiltration. 1 This buffering technique has Level I-II evidence supporting its use. 1
Safety Considerations
Use the lowest effective dose and concentration to minimize systemic toxicity risk, which occurs in approximately 11% of cases after subcutaneous wound infiltration. 3
Maximum safe doses for infiltrative anesthesia: 1
- Adults: 4.5 mg/kg lidocaine without epinephrine; 7.0 mg/kg with epinephrine
- Children: 1.5-2.0 mg/kg without epinephrine; 3.0-4.5 mg/kg with epinephrine
Aspirate before each injection to avoid intravascular administration and use incremental injections while continuously monitoring the patient for early signs of toxicity (circumoral numbness, metallic taste, dizziness). 1
Common Pitfalls
While needle trauma to underlying structures can occur (18 of 124 cases showed median nerve damage evidence during carpal tunnel release), no long-term symptoms or signs related to this damage were found at follow-up. 2 The benefits of direct infiltration outweigh these transient risks when proper technique is employed.