Many benefits are reported after laparoscopy. As experience, equipment, and techniques have improved, minimally invasive laparoscopic surgery is being applied to younger children. With the advent of this new surgical approach, specific modifications become necessary in anesthetic techniques. During laparoscopy, the pneumoperitoneum performed by peritoneal insufflation of CO2 may induce intraoperative ventilatory and hemodynamic changes that complicate anesthetic management. We present a case of laparoscopic Duhamel operation in a 10-month-old infant weighing 10 kg. After induction with thiopental sodium and vecuronium, anesthesia was maintained with enflurane and 50% nitrous oxide in oxygen. Rapid hypercarbia developed about 5 minutes after introduction of pneumoperitonium, so we gave intermittent manual hyperventilation to avoid hypercarbia untill we finished the surgery. In children, CO2 absorption may be more efficient due to the physiological properties of the immature peritoneum. The functional residual capacity (FRC) is low in children. During laparoscopy, FRC is decreased further due to a variety of factors. In spite of the changes in FRC, arterial oxygenation has not been shown to deteriorate in normal infants. In our case, the changes in end-tidal CO2 tension (PETCO2) during laparoscopy did not influence the hemodynamic change. But insufflation of CO2 induced a significant increase in PETCO2, and produced a fast reaction time of PETCO2.