Apron protects operators from radiation but at cost to patients

Draping a lead apron over patients during transradial PCIs reduced radiation to operators but it almost doubled exposure to their patients. Still, researchers argued that the benefit to physicians outweighed the risk to patients.

Anees Musallam, MD, of the cardiology department at Rambam Medical Center in Haifa, Israel, and colleagues are not the first to propose using a lead covering on patients during cardiac catheterization procedures as a way to cut radiation scattering to interventional cardiologists and staff. But they may be the first to assess the consequences in patients.

At the 2014 American College of Cardiology conference, for instance, researchers from Canada reported that they sliced the radiation dose to operators by 75 percent with a combination of a lead shield on patients and a nonlead cap on the physicians. They did not measure patient exposure directly, though.

In the study published online Feb. 3 in Catheterization and Cardiovascular Interventions, Masallam et al described their use of a 0.5-mm lead apron that covered patents’ abdomen and upper thighs during radial catheterization procedures. To assess radiation exposure to both operators and patients, they randomized patients to either wear the lead pelvic shield (162 patients) or not (160 patients). Operators donned standard protective gear.

They placed eight dosimeters in various locations on the operator, patient, shield and image receptor to measure radiation. Patient characteristics were similar and there was no statistical difference in fluoroscopy time.

Use of the lead apron cut radiation exposure to operators on all three sites where it was measured: under the operator’s lead apron, 0.53 μSv with no shielding vs. 0.17 μSv with shielding; on the thyroid collar, 5.9 μSv vs. 2.9 μSv; and on the left side of the head, 3.3 μSv vs. 2.1 μSv.

Patient exposure, with and without the apron, was 28.9 μSv vs. 15.4 μSv, though. The finding raises concerns about patient safety, Musallam et al acknowledged. But as other have emphasized, the operator’s exposure occurs repeatedly over a career while the patient’s is often a single experience.

Their institution has since chosen to make use of the apron standard practice in radial procedures. “We currently believe that reducing scatter radiation is of major importance and its benefit [for the operator] outweighs the risk [for the patient],” they wrote. “However, this balance has to be further confirmed and taken into account in every catheterization laboratory, before the widespread implantation of using a lead apron shield.”  

They described their research as exploratory and added that a larger study should be conducted.