RESUMO
This case report describes a patient who developed allergic contact dermatitis to a chlorhexidine skin preparation applied for a transversus abdominis plane block, but not to a different chlorhexidine solution applied to the surgical field. The patient had presented for an elective inguinal hernia repair. He had a known history of anaphylaxis to non-steroidal anti-inflammatory medication but was otherwise well. The surgery was completed uneventfully. Three or four days postoperatively, the patient developed a rash at the site where chlorhexidine skin preparation had been used to prepare the skin for the transversus abdominis plane block. The rash had well-demarcated edges and exactly matched the distribution of the previously applied skin preparation. No rash was present at the surgical site, which had been prepared with a different chlorhexidine-containing solution. The rash gradually resolved over several weeks with the application of topical corticosteroids. The patient was otherwise completely well with no evidence of infection or any other systemic illness. The skin preparations differed in the dyes and alcohols that they contained. The dyes or alcohol in the preparation for the transversus abdominis plane block were therefore considered the likely cause of this patient's allergic reaction. Dyes and alcohols should be considered as a cause of skin allergy in the perioperative setting.