Pneumoperitoneum is recognized as a benign and self-limiting finding after the insertion of a percutaneous endoscopic gastrostomy (PEG) tube, while complicated pneumoperitoneum is rarely reported. The aim of this study was to reappraise pneumoperitoneum following PEG.

We retrospectively reviewed 193 patients who underwent PEG from May 2008 to May 2014. All patients had a follow-up upright chest or simple abdominal radiograph after PEG. Pneumoperitoneum was quantified by measuring the height of the air column under the diaphragm and graded as small (<2 cm), moderate (2-4 cm), or large (>4 cm). Clinically significant signs were defined as fever, abdominal tenderness or leukocytosis occurring after PEG insertion.

Of the 193 study patients, 9 (4.6%) had a pneumoperitoneum visualized by radiographic imaging, graded as small in 5 patients, moderate in 2 patients and large in 2 patients. Clinically significant signs were observed in 5 (55.5%) patients with fever reported in 4 patients, abdominal tenderness in 4 patients and leukocytosis in 4 patients. The time to resolution of free air was 2-18 days. Two patients (22.2%) with moderate or large pneumoperitoneum after PEG died from either pneumonia or septic shock.

The clinical course of pneumoperitoneum after PEG is not always benign and self-limiting. These findings suggest that clinicians should not neglect a moderate or large pneumoperitoneum, particularly in patients who have an altered mental status or received antibiotics, since peritoneal irritation cannot be observed under these circumstances.