From the Guidelines
Oral contrast is contraindicated in patients with ileus, as it can delay diagnosis, increase patient discomfort, and increase the risk of complications, particularly vomiting and aspiration. When a patient has an ileus, the normal propulsive movements of the intestines are impaired or absent, which means that orally administered contrast material will not move through the gastrointestinal tract properly. This stasis can lead to prolonged retention of contrast in the bowel, potentially worsening the patient's condition and providing limited diagnostic value. According to the American College of Radiology, patients with a suspected high-grade obstruction do not require any oral contrast medium because the nonopacified fluid in the bowel provides adequate intrinsic contrast 1.
Instead, intravenous contrast is typically preferred for imaging studies in patients with suspected ileus, as it does not rely on gastrointestinal motility. If imaging is necessary in a patient with ileus, a non-contrast CT scan or a CT scan with IV contrast alone may be more appropriate. The use of oral contrast in these cases could potentially exacerbate symptoms, cause vomiting, and increase the risk of aspiration, particularly in patients who already have abdominal distention and nausea. Key points to consider include:
- The potential for oral contrast to delay diagnosis and increase complications
- The limited diagnostic value of oral contrast in patients with ileus
- The preference for intravenous contrast or non-contrast CT scans in these cases
- The importance of considering the patient's overall condition and potential risks when deciding on imaging protocols, as noted in the study on suspected small-bowel obstruction 1.
From the Research
Oral Contrast in Ileus
- There is no direct evidence in the provided studies that oral contrast is contraindicated in ileus 2, 3, 4, 5, 6.
- The studies primarily focus on the comparison of different oral contrast agents for abdominopelvic CT scans 3, 4, 6 and the use of oral contrast in patients with acute non-traumatic abdominal and pelvic pain 5.
- One study discusses ileus in critically ill patients, but it does not mention the use of oral contrast in this context 2.
- Another study suggests that the use of positive oral contrast material for abdominal CT is a frequent protocol issue, and its use should be driven by patient-specific considerations rather than throughput concerns 4.
- The current role of oral contrast in CT scans for patients with acute non-traumatic abdominal and pelvic pain is also discussed, with recent research supporting the omission of positive oral contrast in most clinical situations 5.