Case: If a Patient comes with acute abdominal pain and we’re suspecting intestinal, duodenal or gastric perforation meaning that we are looking for pneumoperitoneum, and we asked for chest X-ray upright but we didn’t see free air under the diaphragm, what do we do next?

- Left lateral decubitus X-ray: We let the patient lie on his left side and we do an X-ray. It is on the left and not right side because if he lies on his right side the air of the stomach remains high so we don’t know if the air is from the stomach or peritoneum, while in the left position the air accumulates above the liver or intestine so it shows easily. - If were also suspecting intestinal perforation and we did both chest X-ray upright and left lateral decubitus and free air didn’t appear, we can do scan to see free air (if there’s a scan because some hospitals don’t have one). - If can’t do scan, we then do a test that assures us of whether we have perforation or not: We put an angi-tube (nasogastric tube) NOTE endoscopy is CI