Erect chest x-ray (summary)

Dr Jeremy Jones et al.

Erect chest x-rays are standard positioning but are also a specific examination performed for the assessment of subdiaphragmatic free gas (pneumoperitoneum).

Reference article

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  • indications (acute)
    • concern for pneumoperitoneum, e.g. bowel perforation
  • important pathology
    • pneumoperitoneum
  • benefits
    • quick and accessible
    • relatively sensitive for free intraperitoneal gas
  • limitations
    • sick patients may not be able to sit up for long enough (10 minutes)
    • doesn't help with the cause of perforation
    • modest radiation dose
  • procedure
    • patient positioned erect (sitting) for 10 minutes
      • required to allow gas to settle in the subdiaphragmatic space
    • chest x-ray performed in sitting position
  • similar tests
    • chest x-ray
      • may be performed in a variety of positions
      • no delay to allow gas to rise to the top of the abdomen if erect
    • CT abdomen
      • tiny amounts of free gas can be identified
      • often able to help determine the cause of perforation

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rID: 47293
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Cases and Figures

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    Subdiaphragmatic free gas
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    Free subdiaphragmatic gas
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