In the United States, sigmoid volvulus tends to occur in older men and residents of nursing homes and mental hospitals, in whom chronic constipation and obtundation from medication are predisposing factors for gaseous distention of the sigmoid colon and stretching of the sigmoid mesocolon. (Courtesy Laura R. Carucci, MD, Richmond, VA.), Air is seen collecting centrally in the biliary tree (, Click to share on Twitter (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Google+ (Opens in new window), Perfusion Computed Tomography and Magnetic Resonance Imaging in the Abdomen and Pelvis. I feel like the normal dose isn't working for this. Air escaping from a perforated viscus may become loculated in this space because of surrounding inflammation. Occasionally, this sign may be seen in adults. Portal venous gas has even been described as a transient finding on Doppler ultrasound during the early postoperative period after liver transplantation. The symptoms are usually acute, but they may have a gradual onset in some patients. Eating disorders include a spectrum of disordered thinking patterns and behaviours around eating. What Is A Normal Bowel Gas Pattern? In the supine position, fluid may gravitate to this space. Air-fluid levels on upright view, in colon. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. Overall, sigmoid volvulus accounts for 1% to 2% of all intestinal obstructions in the United States. Inspissated feces and calcium salts may adhere to the nidus, so it eventually reaches a size that occludes the appendiceal lumen. Two separate air-fluid levels can sometimes be seen in the dilated transverse colon, a finding that helps differentiate volvulus of the transverse colon from cecal volvulus. Half of small bowel. Underlying causes of this life-threatening condition include ingestion of caustic substances, severe gastroenteritis, and gastroduodenal surgery that compromises the vascular supply of the stomach. The gallbladder may also be visualized. Finally, when patients swallow little or no air, abdominal radiographs may reveal multiple tubular, sausage-shaped soft tissue densities representing fluid-filled loops of small bowel without any intraluminal gas in the small bowel or colon, producing a so-called gasless abdomen. The clinical decision making of patients with suspected or diagnosis and treatment of small bowel obstruction, a known SBO because it can answer specific questions that common clinical condition often associated with signs have a major impact on clinical management [2]. } Chest X-Ray showed evidence of acute pulmonary injury and edema. These cookies will be stored in your browser only with your consent. An acute abdominal series showed a nonspecific bowel gas pattern with moderate distention of the stomach and duodenum near the duodenojejunal junction on the anteroposterior view along with air-fluid levels on the lateral view ().A subsequent upper gastrointestinal (GI) series confirmed prominent fluid-filled dilation of the proximal small bowel concerning for a mid small bowel obstruction . Location of gas on the abdominal x-ray may suggest the the underlying cause. However, subsequent investigators have found that differential air-fluid levels may be present in any tubular viscus containing air and fluid. Only $35.99/year. This chapter focuses on the abnormalities of gas and soft tissues that can be detected on abdominal radiographs. Obtaining an accurate diagnosis opens up potential treatment options, including the use of prescription medication to reduce your gas. Radiologists should always be aware of the potential risk of rectal perforation when insufflating a balloon during barium enemas. Various causes of free air are listed in Table 12-1 . Linear collections of gas may also be seen in the subhepatic space, although the latter finding must be differentiated from subhepatic fat. If prone or decubitus views of the pelvis show free passage of gas into the rectum, sigmoid volvulus therefore is extremely unlikely. Although CT and ultrasound provide more information about acute abdominal conditions, abdominal radiography has the advantages of relatively low cost and ease of acquisition and can readily be performed on acutely ill or debilitated patients, so it remains a valuable study for the trained and perceptive observer. 12-2A ). may be indistinguishable, such as different infectious pneumonias. Radiographic evaluation of intestinal gas should include the following: (1) identification of the bowel segments containing gas; (2) assessment of the caliber of these segments; (3) assessment of the most distal point of passage of gas; and (4) evaluation of the bowel contour outlined by gas. The diagnosis of toxic megacolon usually is made based on a combination of the clinical and plain film findings, so a contrast enema does not need to be performed in these patients. I'm coding an OP Radiology report and the impression is "Nonspecific bowel gas pattern may represent aerophagia versus ileus" I know I can't code the "versus" dx, but do I need to code the nonspecific bowel gas pattern at all or just use the reason. I'm having 2 BMs a day (although they are very thin) so I'm guessing this is why my primary doc doesn't seem to concerned, but the pain in my lower left abdomen is excrutiating on and off pain! Mortality rates as high as 33% have been reported in these individuals. Air accumulating superiorly in the free space between the anterior aspect of the liver and the abdominal wall may cause increased lucency in the right upper quadrant ( Fig. Radiographic evaluation of intestinal gas should include the following: (1) identification of the bowel segments containing gas; (2) assessment of the caliber of these segments; (3) assessment of the most distal point of passage of gas; and (4) evaluation of the bowel contour outlined by gas. Thus, a delayed diagnosis of toxic megacolon on abdominal radiographs may have disastrous consequences for these individuals. The EGD further revealed 1 nonbleeding duodenal ulcer covering half of the duodenal bulb circumference with a cratered area representing a fistula tract, also known as Ulcre . In one study, one or more signs of pneumoperitoneum were present on these radiographs in 59% of patients. font-weight: normal; There are several ways to deal with uncomfortable intestinal gas: 1. It basically means that the appearance of bowel is unclear on the X-ray and can be normal or abnormal. It may be caused by some combination of edema, fluid, and abscess formation in the right lower quadrant. (D) Abnormal but nonspecific gas pattern. 12-3 ), so the absence of colonic distention in no way excludes this condition. Abdominal radiographs may reveal a dilated, featureless, air-filled loop of bowel in the left upper quadrant that is separate from the stomach, with air-fluid levels in the transverse colon and cecum. Although the location of intestinal gas is helpful in differentiating colon from small bowel, recognition of intestinal folds is also important. While there appears to be a modest early peak of non-specific inflammation, we were surprised to identify such efficient discrimination . Gas in the wall of the small bowel, which is termed pneumatosis intestinalis, is characterized by two radiographic patternsa bubbly appearance or thin, linear streaks of gas. Intraperitoneal air that traverses the foramen of Winslow may become trapped in the lesser sac. He coordinates the Alfred ICUs education and simulation programmes and runs the units educationwebsite,INTENSIVE. Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. 12-8 ). Gastric ulcers and masses are also occasionally visible ( Fig. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. The stomach may also be dilated because of gastroparesis or gastric atony from diabetes (gastroparesis diabeticorum), which is almost always associated with a peripheral neuropathy. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. Gas on both sides of the bowel, however, may outline the bowel wall as a thin linear stripe ( Fig. Unless the gas has been introduced iatrogenically by vascular catheterization, endoscopic manipulation, or other iatrogenic causes, the source of the gas is almost invariably the intestine. This website uses cookies to improve your experience while you navigate through the website. The patient had improvement in symptoms, and was tolerating a clear liquid diet. Pass it rectally, which is increased with movements such as walking or lifting 2. An air-fluid level may also be present in the cecum on upright or decubitus abdominal radiographs, but this finding is transient and nonspecific. Toxic megacolon develops in 5% to 10% of patients with ulcerative colitis, but in only 2% to 4% of patients with granulomatous colitis. Abdominal radiographs are usually not helpful for patients with volvulus of the transverse colon and may erroneously suggest sigmoid volvulus. } Major signs of free air on supine abdominal radiographs include the following: Gas normally outlines only the luminal surface of the bowel. 12-11B ). Still other patients may have a pseudo-Riglers sign caused by faint residual oral contrast material (usually from recent abdominal CT) coating the luminal surface of the bowel, so the increased density of the wall creates the erroneous impression that gas is present on both sides of the wall. A low-pressure barium enema performed without inflation of a rectal balloon should demonstrate smooth, tapered narrowing, or beaking, at the rectosigmoid junction with associated obstruction. In the absence of a surgical history, an obstructing hernia should be suspected. 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Learn how we can help Reviewed Sep 02, 2021 Thank Dr. Silviu Pasniciuc agrees Dr. Silviu Pasniciuc answered Internal Medicine 29 years experience Duodenal ulcers, iatrogenic duodenal injuries, and blunt abdominal trauma are all possible causes of perforation of the extraperitoneal portion of the duodenum. 38 The flat-line pattern may be clinically important because a significant proportion of patients with this pattern respond . Subjects. An upper endoscopy was also normal. This doesn't help the ordering physician much, except to tell him to use his clinical suspicion to guide further workup. 12-5B ). Preference cookies are used to store user preferences to provide content that is customized and convenient for the users, like the language of the website or the location of the visitor. Bowel gas patterns may point to an underlying cause bowel gas patterns include: Normal Nonspecific Adynamic ileus Mild localized ileus or "sentinel loop" Severe "colonic pseudo-obstruction" Small bowel obstruction; central, valvulae conniventes, pliable ("bent finger") Large bowel obstruction - peripheral, haustra, contains feces Causes Other findings of bowel ischemia or infarction on abdominal radiographs include dilation of bowel and nodular thickening or thumbprinting of the bowel wall. The term "nonspecific gas pattern" is used by radiologists to describe a gas pattern seen in the bowel on an X-ray of the abdomen that may or may not be normal; however, it doesn't meet the criteria for a more precise diagnosis, such as a small bowel obstruction. In some cases, air and intestinal contents may enter the twisted segment of bowel, producing abdominal distention and pain. Colonic dilation (cecum > 9 cm or transverse colon > 6 cm) can be seen in adult patients presenting with a variety of medical and surgical conditions of the abdomen ().Acute or progressive colonic distention may lead to colonic ischemia or perforation, and an accurate diagnosis of the cause of distention is necessary to initiate appropriate therapy and prevent complications. Acute appendicitis with partial small bowel obstruction. The presence of an appendicolith has important implications for patients with appendicitis because it indicates a greater likelihood of superimposed perforation and abscess formation. Retroperitoneal air in a patient with retroperitoneal perforation after endoscopy. The presence of air-filled bowel below either pubic ramus should suggest the possibility of an obstructing inguinal hernia. Other gas collections biliary, intramural, etc. Pneumatosis is particularly well shown by CT, but does not always indicate infarction of the bowel unless the pneumatosis is associated with portomesenteric venous gas. The flat-line pattern, defined as no methane and low fixed hydrogen (3 ppm and no rise >1 ppm above baseline) production (Figure C), 37 is uncommon and more frequently seen in patients with inflammatory bowel disease. . 12-15 ). Serial radiographs showing a change in cecal diameter at 12- to 24-hour intervals may be more helpful than a single radiograph showing a dilated cecum. In some areas of South America and Africa, the incidence of sigmoid volvulus is extraordinarily high, reportedly because of a high-fiber diet and the resultant large, bulky stools, producing a chronically dilated, elongated sigmoid colon that predisposes patients to this type of volvulus. Inflammation and edema may alter the water content of surrounding fat and obscure the normal fat planes of the psoas muscle, obturator muscle, or properitoneal flank stripe. This topic is discussed in detail in Chapter 46 . Enterography protocol computed tomography revealed small bowel inflammation involving 15 centimeters of the terminal ileum. Dilation of the stomach and small bowel may allow air to enter the intestinal mucosa, eventually reaching the liver. 12-11C ) or extrahepatic segment of the ligamentum teres in the right upper quadrant, the lateral umbilical ligaments (inverted V sign) in the lower abdomen, and the urachus. Compression of the duodenojejunal junction at the root of the mesentery may cause severe vomiting. The bubbly appearance of intramural gas is easily mimicked by fecal material within the colon. The duodenum may be filled with fluid, so it is not readily visible on supine radiographs. Plain abdominal radiographs revealed a non-specific bowel gas pattern (Fig. This finding is nonspecific, however, and can be related to patient positioning. In his classic work on the acute abdomen, Frimann-Dahl stated that the presence of air-fluid levels at two different heights in the same loop of small bowel indicates a hyperperistaltic small intestine and is therefore a sign of small bowel obstruction. He is one of the founders of theFOAMmovement (Free Open-Access Medical education) and is co-creator oflitfl.com,theRAGE podcast, theResuscitologycourse, and theSMACCconference. Localized inflammation and edema may cause thickening of the cecal wall and widening of haustral folds in this region. Paralytic ileus happens if the nerves in the . As small bowel obstruction progresses, gas-filled small bowel loops proximal to the site of obstruction become more dilated and tend to have a horizontal orientation in the central portion of the abdomen, producing a classic stepladder appearance. We found the definition to be dichotomous and asynchronous between radiologists and their referring physicians. LOW:Anaemia, Hypocalcaemia, hypochloraemia, Hypomagnesaemia. After 24 hours of intensive treatment, the patient expired. You may: Feel bloated. In patients with this form of pneumatosis, close inspection may reveal small bubbles of gas outside the confines of the bowel, leading to the correct diagnosis. A nodular mucosa may be visible in the dilated transverse colon as a result of inflammatory pseudopolyps in patients with ulcerative colitis (see Fig. Nevertheless, a definitive diagnosis can be made only at surgery. The most common causes of obstruction include acute edema and spasm from an ulcer in the distal antrum or pyloric channel or chronic antral narrowing secondary to scarring from a previous ulcer. Current concepts in. Cecal volvulus should be differentiated from a prolonged colonic ileus in bedridden patients with a persistent mesentery on the ascending colon because the anteriorly located cecum in these patients may become disproportionately dilated, mimicking the appearance of a cecal volvulus. Chest radiographs obtained with the patient in an upright position are ideal for demonstrating free air because the x-ray beam strikes the diaphragms tangentially at their highest point. padding-bottom: 0px; In case of sale of your personal information, you may opt out by using the link. Home. The most important consideration in the differential diagnosis of pneumobilia is the presence of gas in the portal venous system (see later, Portal Venous Gas ). Occasionally, a massively dilated, fluid-filled stomach can mimic the appearance of ascites or hepatomegaly. Answer: B, If the visualized bowel gas in your imaging study was unremarkable,Pneumatosis intestinalis (PI), 2013), 22% meaning, 22% meaning, defined as gas within the bowel wall, Radiograph shows a nonspecific bowel gas pattern with no signs of bowel obstruction, treatment with intravenous fluids, An ultrasound study is ordered to confirm the . Small amounts of gas (arrows) are noted in nondistended small bowel loops in left hemiabdomen and pelvis in addition to usual gas in distal. What can you do to release trapped bowel gas? They emphasized that the duration of cecal distention was more important than cecal diameter in predicting impending perforation. A wealth of diagnostic information can be obtained from correct interpretation of abdominal radiographs, and several excellent texts are available on the subject. Meyers has described the various pathways in which retroperitoneal gas can travel. The concept of a cecal bascule was challenged by Johnson and colleagues, who believed that these patients have a focal adynamic ileus of the cecum. Cecal volvulus may occur in a variety of settings, including colonoscopy, barium enema, obstructive lesions in the distal colon, and pregnancy. An adynamic ileus occurs as a response to focal inflammation and may be localized to the right lower quadrant (also known as a sentinel ileus). The gas-filled small bowel tends to occupy the central portion of the abdomen and has a smaller caliber than the colon. This will fall in between the normal bowel and grossly abnormal blocked bowel. In 1938, Weinstein described a condition known as cecal bascule, which involved folding of the right colon without twisting, so the cecum occupied a position in the midabdomen. However, the mortality of SBO ranges from 2% to 8% and may increase to as high as 25% if bowel ischemia is present and there is a delay in surgical management ( 2 - 5 ). These patients have a persistent mesentery on the ascending colon and, because of its greater mobility, the ascending colon can twist on its mesentery, producing a volvulus. Pneumatosis intestinalis and portal venous air (pneumoportogram) can both be seen on radiographs and with ultrasound. An incompetent sphincter of Oddi, recent sphincterotomy or sphincteroplasty, anomalous insertions of the biliary tree, recent passage of a common duct stone, and infestation of the biliary tract by Ascaris are other causes of pneumobilia. A "definite" SBO pattern is defined as abnormal and clearly disproportionate gaseous and/or fluid distention of small bowel relative to the colon (or other segments of small intestine). Study with Quizlet and memorize flashcards containing terms like Small and Large Bowel General Complaints, General Diagnostics for Abd Complaints, Bowel Obstruction Complaints and more. Any segment of intestine that has a mesenteric attachment has the potential to undergo a volvulus. In patients with a competent ileocecal valve, the colon (especially the cecum) may become markedly dilated, and little or no gas may be seen in the small bowel. View larger version (158K) Fig. Severe vascular compromise may result in necrosis and perforation of bowel, causing sepsis and death. Postoperative ileus mimicking small bowel obstruction. The peripheral location of the gas reflects the hepatopetal flow of blood in the portal venous system away from the porta hepatis. Absence of a changing bowel pattern over time is worrisome. More than 50% of colonic obstructions are caused by annular carcinomas of the colon. Although some patients with suspected toxic megacolon have undergone barium enemas, most authors believe that such examinations are contraindicated because of the risk of perforation. Created for people with ongoing healthcare needs but benefits everyone. The obstruction usually occurs in the sigmoid colon, where the bowel tends to have a narrower caliber and the stool is more solid. Upright or left lateral decubitus abdominal radiographs are based on the principle that air rises to the highest point in the peritoneal cavity. A complete blood count, chemistry panel, and serum pregnancy testing were normal. Persistence of the dilated loop on sequential radiographs over several days should increase concern for a closed loop obstruction. Whether cecal bascule represents an actual anatomic folding of the right colon or an adynamic ileus is not as important as the recognition that a dilated, ectopically located cecum may be a source of abdominal symptoms and potential cecal perforation. Undefined cookies are those that are being analyzed and have not been classified into a category as yet. There may be a few loops of bowel which are abnormal but not conclusive for a bowel blockage. 1 A). Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. A normal small bowel gas pattern varies from no gas being visible to gas in three or four variably shaped small intestinal loops. 12-9 ). Traumatic injury to the common bile duct as a complication of endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy has also been reported as a benign cause of portal venous gas. Abdominal radiographs are often performed as an initial imaging test in patients with abdominal pain and distension. . . Perhaps there may be a dilated look or air fluid levels but the radiologist is not sure. Key Words Abdominal diseases diagnostic radiology observer performance radiology reporting systems This central location is explained by the flow of bile from the periphery of the liver toward the porta hepatis. This condition is characterized by linear collections of gas in the wall or stomach. Normal bowel gas pattern B. post-sexual activity, spa bath, water ski-ing), Hepatodiaphragmantic interposition of the colon, Secondary to colonic distention (obstruction or ileus), Gallstone ileus (biliary-enteric fistula) [, Hepatic portal venous gas (bowel infarction), Hydrogen peroxide ingestion (or other gas forming substance). If immediate surgery is not contemplated, further radiographic work-up with computed tomography (CT) is usually indicated. Supine abdominal radiograph shows a laminated appendicolith (, There is marked colonic distention in a patient with ulcerative colitis and toxic megacolon. A soft tissue mass can be found in up to one third of patients with perforation. Prolonged cecal distention beyond 2 to 3 days should prompt colonoscopic or surgical decompression. Bone calcification in RLQ -Osteophytes 5. The amount of gas within a loop of bowel may significantly underestimate its caliber. Iatrogenic trauma is a common cause of rectal perforation. Bowel gas patterns may point to an underlying cause bowel gas patterns include: Anosmia, Ataxia, Blepharospasm, Bulbar and Pseudobulbar palsy, Central Pontine Myelinosis, Cerebellar Disease, Chorea, Cranial nerve lesions, Dementia, Dystonia, Exophthalmos, Eye trauma, Facial twitches, Fixed dilated pupil, Horner syndrome, Loss of vision, Meningism, Movement disorders, Optic disc abnormality, Parkinsonism, Peripheral neuropathy, Radiculopathy, Red eye, Retinal Haemorrhage, Seizures, Sudden severe headache, Tremor, Tunnel vision, Bronchial breath sounds, Bronchiectasis, High airway pressures, Massive haemoptysis, Sore throat, Tracheal displacement, Atrial Fibrillation, Bradycardia, Cardiac Failure, Chest Pain, Murmurs, Post-resuscitation syndrome, Pulseless Electrical Activity (PEA), Pulsus Paradoxus, Shock, Supraventricular tachycardia (SVT), Tachycardia, VT and VF, SVC Obstruction, Abdominal distension, Abdominal mass, Abdominal pain, Asterixis, Dysphagia, Hepatomegaly, Hepatosplenomegaly, Large bowel obstruction, Liver palpation abnormalities, Lower GI haemorrhage, Malabsorption, Medical causes of abdominal pain, Rectal mass, Small bowel obstruction, Upper GI Haemorrhage. Supine abdominal radiograph in a patient with sigmoid volvulus shows a massively dilated loop of sigmoid colon extending superiorly into the right upper quadrant and elevating the right hemidiaphragm, with no gas seen in the rectum. These cookies do not store any personal information. Otherwise, bothersome gas is generally treated with dietary measures, lifestyle modifications or over-the-counter medications. You can also place a warm, wet washcloth. Radiologists use the term nonspecific gas pattern to denote a gas pattern that is not quite normal but that does not fulfill the criteria of a more specific diagnosis such as small bowel obstruction. Scoliosis 2. However, the routine KUB is neither sensitive nor specific for obstruction and many patients in the ER will have a "non specific" bowel gas pattern requiring . Treatment If your gas pains are caused by another health problem, treating the underlying condition may offer relief. Morisons pouch is an intraperitoneal recess bounded anteriorly by the liver and posteriorly by the right kidney. Unlike patients with true cecal volvulus, however, cecal pseudovolvulus is associated with diffuse colonic distention, so it is usually possible to differentiate these conditions on the basis of the radiographic findings. Page Contents1 OVERVIEW2 ORIENTATIONS USED FOR ABDOMINAL X-RAYS3 ANATOMY ON ABDOMINAL X-RAY4 APPROACH (GECkoS)5 GAS PATTERN (INTRALUMINAL)6 EXTRALUMINAL GAS7 CALCIFICATIONS8 SOFT TISSUE MASSES OVERVIEW This page is dedicated to providing a guide on the approach to interpreting an abdominal X-ray. 5-Step Plan To Eliminate Heartburn, Acid Reflux and Related GI Disorders! Gastric volvulus is discussed in Chapter 34 . Flat and upright abdominal radiographs revealed a nonspecific bowel gas pattern and no evidence of obstruction. Pancreatitis or gastritis may also result in reflex gastric atony, and general anesthesia may occasionally cause marked gastric dilation. Initially radiographs are nonspecific and may only show bowel dilatation. Specific clinical information, including time course and onset of disease, patient risk factors, and any recent pharmacologic or radiation therapy, is often instrumental in refining . The term adynamic ileus refers to dilated bowel in the absence of mechanical obstruction. Mechanical obstruction is the other main category of abnormal bowel gas pattern. #mergeRow-gdpr { In general, the small bowel is smaller than 3cm in diameter and the colon is smaller than 5cm in diameter. 12-2B ), or even a polypoid or annular carcinoma (see Fig. term "non-specific bowel gas pattern," and inclusion of patients who have under - gone recent surgery in whom the differ-entiation of ileus from SBO is difficult. Buckinghamshire, United Kingdom) overnight at 30 V. Nonspecific binding was blocked by incubation of the membrane with 5% bovine serum albumin/Tris . The characteristic findings of cecal volvulus, which are present on abdominal radiographs in about 75% of patients, consist of a markedly dilated, gas-filled cecum containing a single air-fluid level in an ectopic location ( Fig. Even with the widespread availability of cross-sectional imaging studies, abdominal radiography remains a common imaging test in modern radiology practice. In contrast, emphysematous gastritis is a rare fulminant variant of phlegmonous gastritis; hemolytic Streptococcus is the most commonly implicated organism. Chris is an Intensivist and ECMO specialist at theAlfred ICU in Melbourne. He is on the Board of Directors for theIntensive Care Foundationand is a First Part Examiner for theCollege of Intensive Care Medicine. Radiographs obtained in midinspiration or midexpiration are even more likely to reveal subtle findings of pneumoperitoneum. This has been described as cecal pseudovolvulus. All these terms refer to a state of decreased or absent intestinal peristalsis, causing swallowed air to accumulate in dilated bowel. Toxic megacolon, or toxic dilation of the colon, may be diagnosed on the basis of a dilated colon on abdominal radiographs in patients with fever, tachycardia, and hypotension. The abdominal x-rays obtained during admission and 1 hour before her upper esophagogastroduodenoscopy (EGD) revealed a nonspecific bowel gas pattern (Figure 1A and B). #mc_embed_signup { Although properly performed upright chest radiographs are extremely sensitive for detecting pneumoperitoneum, abdominal CT has been shown to be even more sensitive for detecting tiny amounts of free air in patients with acute trauma. Mr. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.