Subkutane Infusionsanästhesie (SIA) mit durch Ringer-Lösung verdünntem Prilocain

Background: Dermatologic surgery is usually possible under local anesthesia, even when large amounts of highly diluted anesthetic solutions 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. We have overcome this handicap by injecting anesthetic solutions slowly with an Infusomat, which allows slow painless automatic infusion into the subcutaneous layer. Method: The speed of infusion varied between 40 ml and 1500 ml per hour depending on location, size of the operation, and needle size.Volumes usually ranged from 1 ml to 500 ml but rose as high as 1000 ml if necessary. We found it easier to inject larger amounts than with the conventional method. We used 21-gauge to 30-gauge needles with a length of 1 to 10 cm. The anesthetic solution was prilocaine (Xylonest®), and the dilution liquid was original Ringer's solution in 500 ml bottles with no additives. The concentration of the solution varied between 0.4% and 0.1%. After setting up the system,the physician even can leave the room. Especially for children and very anxious patients, this feature is calming. Material: We used this type of subcutaneous infusion anesthesia (SIA) 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 other operations as well. Results: There were no severe complications. Postoperative recovery was fast. 110 (91%) of 121 patients who had previously experienced other forms of anesthesia for the same kind of operation preferred SIA. Conclusions: SIA Ringer's solution diluted prilocaine is an economical, safe and comfortable technique for nearly all skin operations, even for children and very sensitive patients.