Acute Abdomen Series on a Patient Who Cannot Stand
A 60-year-old woman, two days after sigmoid colectomy with a new left-sided colostomy, has abdominal distension and an NG tube. The order reads "acute abdomen series: supine and upright abdomen." She cannot stand: she becomes hypotensive and lightheaded when the head of the bed is raised past 30 degrees, and she has significant incisional pain. She is alert and oriented, afebrile, heart rate 104, blood pressure 108/66 supine. The surgeon's note asks specifically whether there is free intraperitoneal air.
1. What is the upright view for, and what can you substitute without losing the answer to the surgeon's question?
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Purpose of the upright film: free intraperitoneal air rises to the undersurface of the diaphragm and is visible only with a horizontal beam. The secondary purpose is air-fluid levels.
Substitutes, and what each preserves:
- Left lateral decubitus, horizontal beam - the standard substitute. Free air rises to the highest point, which with the patient on her left side is between the liver and the right lateral abdominal wall. This answers the free-air question.
- Supine abdomen - still valid and still needed. It shows bowel gas pattern, ileus vs obstruction, and tube position. It cannot exclude free air, because there is no horizontal beam.
- Erect chest - equivalently unobtainable here.
The judgment point: a supine-only study does not answer the question that was asked. Substituting nothing is worse than substituting the decubitus.
2. Describe the positioning and timing of a left lateral decubitus, and explain why this patient forces a modification.
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Standard technique:
- Patient on her left side, true lateral, arms up and clear of the abdomen.
- Image receptor posterior to the patient, horizontal cross-table beam, centered roughly at the iliac crest.
- Collimate to include the diaphragm down to the iliac crest - a decubitus that cuts off the diaphragm cannot show subhepatic free air.
- Wait 10–20 minutes before exposing. Air needs time to rise; a film shot immediately can be falsely negative for a small pneumoperitoneum.
The modification this patient forces: she has a left-sided colostomy placed two days ago. Lying directly on it is painful, risks contamination of the field, and risks stoma trauma. A right lateral decubitus solves the stoma problem but sends free air to the left, where it competes with gastric and colonic gas and is easy to mistake or to miss.
Therefore: do not silently pick one. Call the radiologist, describe both constraints, and get a decision - typically a left decubitus with padding and careful stoma avoidance, or a right decubitus with the limitation explicitly stated in the report.
3. What is your scope here - what may you do on your own authority, and what requires communication?
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You may: perform the supine view as ordered, and stop or defer any positioning that is unsafe for the patient.
You must communicate before the patient leaves:
- That the upright view could not be obtained and why.
- What substitute was performed and what limitation it carries (a right decubitus, if that is what was chosen, does not cleanly separate free air from left-sided bowel gas).
- The clinical consequence: a negative supine-only study does not exclude free air, and the surgeon is actively asking that question.
Document the attempted positioning, the vital signs that made it unsafe, who was notified and when, and the instruction received. A technologist who quietly omits a view because the patient could not stand has created a false-negative study on paper - the report will read as a completed series.