PAINLESS INFILTRATION ANESTHESIA FOR LID SURGERY - AN INTRAINDIVIDUALRANDOMIZED PROSPECTIVE-STUDY

Background Local anesthetic infiltration before lid surgery causes pai n of varying degrees. To reduce the patient discomfort we have tested the effect of an initial injection of deluted anesthetic prior to the infiltration anesthesia.Patients and Methods During August 1993 and Ap ril 1994 thirteen patients, 21 to 81 years of age had bilateral lid su rgery (4 female; 9 male). Two injection techniques were studied in die se patients intraindividually. Part of the local anesthetic was delute d 1:10 with saline and initially injected on one side only. Three minu tes later infiltration with 2-5 ml of full-strength 2% mepivacaine wit h adrenaline 1:200 000(R) was performed on both sides. Obvious signs o f pain were documented and patients were questioned about their discom fort (score 0-3). Results Five patients were operated for bilateral ec tropium (lateral canthal sling procedure 4, Lazy-T 1), seven patients for dermatochalasis and one patient for brow ptosis. All thirteen pati ents ranked the technique with the initial injection of deluted local anesthetic significantly less painful. 9 of 13 patients had painless l ocal anesthetic infiltration. Only 4 patients reported minor discomfor t during injection of the diluted anesthetic. Onset time and duration of anesthesia was identical in both groups. Conclusion The initial inj ection of a 1:10 diluted local anesthetic allows a significant reducti on of pain during infiltration anesthesia before lidsurgical procedure s. While pH buffering with bicarbonate may cause permanent skin pigmen tation, dilution with physiological saline is an effective and inexpen sive alternative. With this technique even in children local anesthesi a becomes possible.