FROM JACC: CARDIOVASCULAR INTERVENTIONS
Adding some lead shielding in cardiac catheterization labs can cut the amount of radiation that nurse circulators and scrub technologists are exposed to, according to a single-center study of more than 750 patients.
“The simple and relatively inexpensive approach of providing staff members with a dedicated accessory lead shield during cardiac catheterization was associated with a nearly two-thirds reduction in radiation exposure among both nurses and technologists” according to Ryan Madder, MD , and his associates. “The present study is the first, to our knowledge, to observe a similar benefit among nonphysician staff members, an observation that may have important implications for occupational safety in the cardiac catheterization laboratory.”
The report was published in JACC: Cardiovascular Interventions .
SHIELD (Combining Robotic-Stenting and Proactive Shielding Techniques in the Catheterization Laboratory to Achieve Lowest Possible Radiation Exposure to Physicians and Staff) was a single-center, prospective, observational designed study to research radiation exposure levels among physicians and other staff members in cardiac catheterization labs. Dr. Madder, a cardiologist at Spectrum Health in Grand Rapids, Mich., and his colleagues collected radiation exposure information for staff members such as nurse circulators and scrub technologists during August 2015–February 2016 and measured radiation exposure in 764 consecutive cases. Radiation exposure was monitored for these staff members by dosimeters worn on either the left anterior side of the glasses or thyroid collar, and a body dosimeter underneath the lead apparel on the V-neck of their scrub shirt.
The radiation protection used in the study followed standard institutional operating procedures, which includes two shields between the patient and physician, a ceiling mounted upper body shield with a patient contour cutout, and a lower body shield attached to the side of the operating table, extending from the table to the floor. Staff members wore traditional lead garments, consisting of a lead skirt, apron, and thyroid collar. Additional radiation absorbing disposable pads were used as desired by the staff members.
The study was split into two phases to evaluate the effectiveness of accessory shields with phase 1 (401 cases) utilizing traditional protective measures. Phase 2 (363 cases) used the same material as phase I, but a dedicated accessory lead shield was used. For nurse circulators, this shield was placed between the patient and the intravenous medication pole. For scrub technologists, the shield was placed at the foot of the patient’s bed.
Radiation exposure was higher in phase 1 than phase 2 for all workers. In phase I, technologists faced an effective dose normalized to the dose-area product (EDAP) of 2.4 mcSv/(mGy x cm2) x 10-5 per case. This dropped significantly in phase 2 to an EDAP of 0.9per case, a 62.5% lower dose per case (P less than .0001).
Nurses experienced a similar decrease in exposure per case from phase 1 (EDAP 1.1) and phase 2 (EDAP 0.4). This accounted for a 63.6% lower dose per case (P less than .0001).
The contrast delivery system used at the lab did not allow technologists to maximize their distance from radiation sources, so it is unclear whether the results of this study can be extrapolated to centers where technologists do not perform contrast injections.
Dr. Madder and his colleagues pointed out that this research only begins to scratch the surface of the occupational hazards that catheterization laboratory personnel face.“The use of accessory lead shields, which might be effective to reduce staff radiation exposure, will not likely reduce other occupational hazards of working in the catheterization laboratory related to wearing heavy lead garments, including the risks for orthopedic injuries and experiencing chronic work-related pain.”
Corindus Vascular Robotics partially funded this study and has provided research support to Dr. Madder. All other researchers have no financial conflicts to report.
SOURCE: Madder R. JACC: Cardiovasc Interven. 2018 Jan 22;11[2]:206-12 .
