Clinical significance of intraperitoneal air on computed tomography scan after endoscopic submucosal dissection in patients with gastric neoplasms.

BACKGROUND

Perforations are major complications of endoscopic gastric resection, including endoscopic submucosal dissection (ESD), and are generally detected on chest radiography following ESD. We hypothesized that a small amount of free air, defined as "intraperitoneal air," would not be noted on chest radiography. In this study we aimed to determine how often intraperitoneal air is seen on a computed tomography (CT) scan after ESD and to evaluate the association between clinical factors and intraperitoneal air.

METHODS

A total of 147 patients who underwent ESD for gastric neoplasms were analyzed between September 2009 and September 2010. Patients underwent both chest radiography and noncontrast CT scans. Intraperitoneal air on the CT scan was stratified by the amount of gas as follows: grade I, free air localized along the outside of the gastric wall; grade II, free air in the lesser sac; and grade III, free air in front of the liver.

RESULTS

Intraperitoneal air was detected in 56 patients (38.1 %) by an abdominal CT scan, whereas free air was noted in 2 patients (1.4 %) by chest radiography. Most patients with intraperitoneal air (96.4 %, 54/56) were grade I or II and 3.6 % (2/56) were grade III. Abdominal pain was more frequent in the intraperitoneal air group (32.1 %, 18/56) than in the no intraperitoneal air group (17.6 %, 16/91; P = 0.042). Tumor location at the lesser curvature was more frequent in the intraperitoneal air group (66.1 %, 37/56) than in the no intraperitoneal air group (38.5 %, 35/91; P < 0.001). Fever, use of antibiotics, duration of hospital stay, C-reactive protein level, white blood cell count, complete resection, and local recurrence did not differ between the two groups. All patients who had intraperitoneal air recovered completely with medical treatment.

CONCLUSION

Intraperitoneal air after gastric ESD occurred unexpectedly frequently. However, a small amount of intraperitoneal air on a CT scan does not cause clinically significant complications.