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C - A R M
S A F E T Y
they’re still activating the Xray as their attention shifts
to the procedure’s next step. It’s estimated that 10% to 20% of all radiation is wasted in this manner. Remember: The room is safe as soon as the surgeon takes his foot off the pedal.
By FDA mandate, all fluoroscopes manufactured since 2006 have “last image hold” features, which freeze the pictures captured when physicians lift off the foot pedal. Many mid-grade and high-end models also feature “fluoro loop,” which cycles through the previous 10 to 15 seconds of captured images. Physicians should use these replay modes in place of live fluoroscopy whenever possible.
Recent fluoroscopes display the dose used during the procedure as well as the fluoroscopic time. It makes sense to record these values for every procedure and include this data in a formal quality assurance program.
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DOSE DATA
Radiation Exposure Limits
Under most circumstances, the surgical team’s exposure
should not exceed 10% of ALARA’s annual
thresholds.
MPD* (mrem/year) ALARA† (mrem/year)
-----
Whole body 5,000 500
(head, trunk, arms above
elbows, legs above knees)
-----
Extremities 50,000 5,000
(arms below elbows,
legs below knees)
-----
Individual organs, skin 50,000 5,000
-----
Lens of the eye 15,000 1,500
-----
*MPD = maximum permissible dose
†ALARA = as low as reasonably achievable
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SOURCE: Adapted from the National Council on Radiation Protection and Measurement’s recommendations.
