Hashimoto_2006_Masui_55_1014

We experienced an accidental use of suxamethonium for general anesthesia in a 26-year-old woman with hereditary hypocholinesterasemia that had not been recognized preoperatively. The patient was scheduled for total colectomy as her chronic ulcerative colitis could not be controlled with medications. Routine preoperative screening such as blood cell counts, biochemical data, chest x-ray and electrocardiogram were performed but serum cholinesterase (ChE) activity was not measured. As the preoperative patient condition was good with no abnormal history, anesthesia was induced and maintained with propofol, ketamine and fentanyl as usual. For muscle relaxation, suxamethonium was used for tracheal intubation, and vecuronium was used for the maintenance. After surgery, postanesthetic course was uneventful. One year later, as the patient was pregnant and scheduled for cesarean section, the preoperative screening was done. The biological data showed a hypocholinesterasemia without liver dysfunction. Thus, previous medical records of internal medicine were cheked. Surprisingly the record showed hypocholinesterasemia when she was 15 and 21 years of ages. However, as the physicians did not recognize hypocholinesterasemia, they did not inform the patient of it. Why did the patient have no prolonged apnea and emergence after the previous anesthesia? As the surgical time was exceeded 4 hrs, plasma suxamethonium could fortunately be less than its effective concentration at emergence. However, this case strongly suggests us that preoperative screening should be done without any omission. In addition, if serum ChE activity is not examined, use of suxamethonium should be avoided.