Slow infusion tumescent anesthesia.

BACKGROUND

Dermatologic surgery is usually possible under local anesthesia, even when large amounts of highly diluted anesthetic solution are required (tumescent anesthesia). Although special pumps now render such large injections effortless, it is usually still necessary to hold and guide the injection cannula.

OBJECTIVE

We have found it possible to overcome this handicap by injecting anesthetic solutions slowly with a common infusomat, as in paravenous infusion, into the subcutaneous layer.

METHODS

The method consists of slow, automated tumescent anesthesia by means of infusion. The speed of injection varies between 50 and 1500 mL per hour depending on the location, the size of the operation, and the needle size. Volumes usually range from 2 to 500 mL but may rise as high as 1000 mL if necessary (maximum, 12 mg/kg). We use 30- to 20-gauge needles with a length of 1.5-10 cm and butterfly infusion cannulas. We customarily use an anesthetic solution of prilocaine (Xylonest); the dilution liquid is original Ringer's solution with epinephrine (1:1,000,000) in 500-mL bottles. The concentration of the solution varies between 0.4% and 0.1%. After setting up the system during pulsoxymetry, the physician can usually leave the room. This is calming, especially for children and very anxious patients. We used the slow infusion tumescent anesthesia (SITA) in our department to treat 502 patients ranging in age from 3 to 92 years (mean age, 51 years). We performed all kinds of tumor operations (n = 213), dermabrasions (n = 5), scar revisions (n = 21), stripping of the long and short saphenous veins (n = 82), sentinel node dissection (n = 27), complete lymph node dissection of the axilla (n = 12) and groin (n = 17), and 125 minor operations as well.

RESULTS

There were no severe complications. One hundred ten (91%) of 121 patients who had previously experienced general or regional anesthesia for the same kind of surgery and all who had previously had conventional syringe injection preferred SITA.

CONCLUSIONS

SITA is an economical, safe, and comfortable technique for nearly all skin operations, even for children and very sensitive patients. Choosing the most suitable concentration, needle, needle position, flow ad volume requires some experience.