[Perioperative Management of a Patient with Hereditary Angioedema: A Case Report]

Hereditary angioedema (HAE) is a very rare disease that occurs in about 1 in 50,000 to 150,000 people. HAE is caused by low levels or inproper function of the plasma protein C1 inhibitor (C1-INH) which regulates activation of the complement system and the coagulation system. The typical symptom of HAE is regional swellings without pain nor itching, usually triggered by physical trauma or emotional stress. Unlike allergic edema, HAE attacks do not respond to antihistamines, corticosteroids noradrenaline. The swelling attacks against face and throat are potentially life-threatening, and should be treated as a medical emergency. We report a patient with HAE who underwent radical cystectomy of the upper gum under general anesthesia. Because the oral surgery with tracheal intubation is known to be a risk factor of laryngeal edema in a patient with HAE, she was given C1-INH before operation to prevent laryngeal edema according to HAE Guideline 2010 by the Japanese Association for Complement Research. Her pharynx and larynx were checked with Airwayscope before intubation and with bronchofiberscope before extubation, but no edema was recognized. Postoperatively, she was given C1-INH on the next morning again. She was discharged seven days after operation without any complications.