Reuters article: Portable X-Ray Machine Radiation Dose IsSmall

[Jim Hardeman <Jim_Hardeman@mail.dnr.state.ga.us>]

Portable X-Ray Machine Radiation Dose Is Small 
 
Updated 6:06 PM ET May 17, 2000 
By Will Boggs, MD

WASHINGTON (Reuters Health) - Portable chest x-ray units are mobile x-ray machines that can be wheeled to the bedside of a seriously ill patient. There have been concerns about radiation exposure from use of these machines. But new study findings show that patients who require multiple portable chest x-rays while being treated in intensive care units generally receive safe levels of radiation exposure.

In the United States, the average background radiation exposure is between 450 and 500 milliroentgens, explained Dr. Meenakshi Bhalla-Pandit from Louisiana State University Health Science Center in New Orleans. For diagnostic radiology purposes, roentgens, rads, and rems (relative equivalent mammalian or roentgen equivalent in man) are equivalent radiation exposure units.

Bhalla-Pandit and her colleagues reviewed the medical records of 567 adult patients admitted to intensive care units or step-down units at their hospital to determine the use of portable x-rays and the cumulative entrance skin exposure (ESE, a measure of radiation exposure) in such patients.

During lengths of stay ranging from 1 to 68 days, patients received between 1 and 94 portable chest x-rays each. With an average exposure of 10 milliroentgens per x-ray, this translated to an ESE of between 10 and 940 milliroentgens per patient, Bhalla-Pandit said in a presentation here at the 100th annual meeting of the American Roentgen Ray Society.

Bhalla-Pandit gave the breakdown of ESE ranges received by the patients as follows:

-- 72% of patients received less than 50 milliroentgens (mR), -- 13% received between 60 and 100 mR, -- 6% received 100 to 200 mR, -- 9% received more than 200 mR, -- 1.5% received more than 450 mR.

"Even in the most ill patients," Bhalla-Pandit noted, "exposure was only twice the annual rate of background radiation exposure."

"The benefits of portable chest radiographs clearly outweigh the risks of radiation exposure," she concluded. 

                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
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