Optimal concentration of inhaled oxygen in pediatric patients undergoing laparoscopic choledochal cyst resection under general anesthesia / 中华麻醉学杂志

ABSTRACT

Objective:To determine the optimal concentration of inhaled oxygen in pediatric patients undergoing laparoscopic choledochal cyst resection under general anesthesia.Methods:Seventy-five pediatric patients of both sexes, aged 1-3 yr, of American Society of Anesthesiologists Physical Status classification Ⅱ or Ⅲ, with body mass index of 15-18 kg/m 2, with expected operation time≥3 h, scheduled for elective laparoscopic choledochal cyst resection with general anesthesia, were divided into 3 groups ( n=25 each) using a random number table method: C 40 group (FiO 2=40%), C 30 group (FiO 2=30%) and C 21 group (FiO 2=21%). Blood samples were collected from the radial artery for blood gas analysis after operation for determination of oxygenation index (OI), respiratory index (RI), alveolar-arterial oxygen partial pressure difference (PA-aO 2) and arterial-alveolar oxygen partial pressure ratio (PaO 2/PAO 2). The occurrence of high risk events of hypoxia (SpO 2<94%), extubation time, and occurrence of pneumonia and atelectasis at day 7 after operation were recorded. Results:Compared with C 21 group, PaO 2, PAO 2, PA-aO 2 and RI were significantly increased, PaO 2/PAO 2 was decreased, and the incidence of high risk events of hypoxia was decreased in C 30 and C 40 groups, and the incidence of atelectasis in C 30 group and pneumonia and atelectasis in C 40 group was increased at day 7 after operation ( P<0.05). Compared with C 30 group, PaO 2, PAO 2, PA-aO 2 and RI were significantly increased, and PaO 2/PAO 2 was decreased in C 40 group ( P<0.05). Conclusions:The optimal concentration of inhaled oxygen recommended is 21%-30% in the pediatric patients undergoing laparoscopic choledochal cyst resection under general anesthesia.