The hazards of radiation exposure in the cath lab

The medical device industry is continually improving diagnostic imaging systems in order to lower radiation dose without compromising image quality, and both company articles and studies by cardiologists published in peer-reviewed journals stress the benefits for patients. However, much less emphasis is given to radiation exposure of relevant healthcare workers, a problem that is particularly acute in the catheterization lab where the use of albeit low radiation dose imaging approaches has increased exponentially. Diagnostic procedures utilizing ionizing radiation, such as coronary angiography, are now standard, as are interventions such as coronary artery angioplasty and stenting. Interventions such as atrial fibrillation ablation can take several hours and require up to an hour’s screening time. And the huge growth in the number of trans-catheter aortic valve implantation (TAVI) procedures carried out in the cath lab also impacts on the cumulative radiation dose to which operators are exposed.
The potential hazards of operator exposure include skin erythema from hands being constantly within the primary beam, and damage to eyes. Relatively low radiation doses can irreversibly damage the lens; higher doses can affect the conjunctiva, iris, sclera and retina. And of most concern, increasing radiation exposure can result in irreversible damage to cellular DNA and carcinogenesis; the brain, thyroid and skin are most susceptible to cancers. A survey published earlier this year in the American heart association journal compared 466 healthcare personnel with an average of ten years cath lab experience with 280 personnel working in cardiology but without radiation exposure. The prevalence of skin lesions, cataracts and cancers were all significantly higher in the radiation-exposed group, as were hypertension and orthopedic problems such as back pain. But in the high stress environment of the cath lab, exacerbated because these healthcare workers are frequently on call’ after completing their regular shifts, it is understandable that monthly reports of radiation exposure are not scrutinized by staff, and that effective protective measures such as special glasses, thyroid collars, gloves and lead aprons- the wearing of which has been linked to lower back pain- are not always utilized.
So surely it is essential that hospitals provide intensive training in radiation protection for the whole cath lab team, ensure that all staff know the relevant protocols and adhere to them, and regularly examine shielding equipment for defects. In addition radiation protection supervisors should monitor exposure on a monthly basis, via operator badges and ideally by the systems available that can provide real-time data throughout every procedure involving ionizing radiation.