Anesthetic management for endoscopic surgery in two patients with goiter

We report anesthetic experience of two patients for endoscopic removal of thyroid tumor by new surgical approach. A subplatysmal air pocket, which had been created by using a subcutaneous dissector, was maintained by insufflating carbon dioxide (CO₂) at an insufflation pressure of 6 mmHg. In one patient, the arterial CO₂ pressure increased from 29 mmHg to 44 mmHg, and in another patient from 31 mmHg to 36 mmHg. We did not experience any symptoms of sustained CO₂ absorption such as severe hypercarbia, acidosis, and massive subcutaneous emphysema. The patients were discharged on the fifth and the fourth postoperative day with no complications. The advantages of this endoscopic surgery include little postoperative pain, quick recovery, and short hospital stay after operation. However, possible occurrence of intraoperative hypercarbia during endoscopic surgery must be considered, and continuous monitoring of ventilation by end-tidal CO₂ or arterial CO₂ pressure is mandatory.