Objective:To investigate the characteristics of atelectasis and its relationship with the degree of diaphragm inhibition in elderly patients with artificial pneumoperitoneum under general anesthesia.Methods:Patients of both sexes, aged 20-80 yr, of American society of Anesthesiologists physical status Ⅰor Ⅱ, with body mass index of 20-29 kg/m 2, scheduled for elective laparoscopic cholecystectomy under general anesthesia, were divided into 2 groups ( n=20 each) according to age: young and middle-aged group and elderly group.Total intravenous anesthesia was applied and intraoperative pressure of artificial pneumoperitoneum was set at 10 mmHg.Before anesthesia, at 5 min of mechanical ventilation, at 5 min of artificial pneumoperitoneum, at 20 min of artificial pneumoperitoneum, at 5 min after the end of artificial pneumoperitoneum and at 15 min after extubation, diaphragmatic excursion (DE) was measured at the right diaphragm point using M-mode ultrasound.The minimal DE was recorded and the maximum degree of diaphragm inhibition was calculated.B-mode was used to assess the lung ultrasound images at the upper bedside lung ultrasound in emergency (BLUE) point, the lower BLUE point and the diaphragm point, and the cumulative scores before anesthesia and perioperative maximum cumulative scores of lung ultrasound score (LUS) were recorded. Results:Compared with the young and middle-aged group, the maximum cumulative scores of LUS were significantly increased, the degree of DE before anesthesia, the perioperative maximum degree of diaphragm inhibition were increased ( P<0.05), and no significant change was found in LUS cumulative scores in elderly group ( P>0.05). Conclusion:The degree of atelectasis is more serious in the elderly patients with artificial pneumoperitoneum under general anesthesia, and the mechamism may be related to the increased degree of diaphragm inhibition.