THE EFFECT OF RADIATION SHIELDS ON OPERATOR EXPOSURE DURING CONGENITAL CARDIAC CATHETERISATION.

Abstract

Cardiac catheterisation personnel are exposed to occupational radiation and its health risks. Little data exist regarding the efficacy of radiation-protective equipment from congenital catheterisation laboratories (CLs). The authors retrospectively reviewed data in which CL operators wore a radiation dosemeter during catheterizations on patients of >20 kg. A leaded under-table skirt was present in all cases. Three additional radiation-protective devices were utilised at operator discretion: a top extension to the under-table skirt, a ceiling-mounted shield and a disposable patient drape. Case details, operator position, fluoroscopy time, incident air KERMA in the patient plane (K, mGy) and dose-area product (DAP, µGy·m2) were recorded. A total of 136 catheterizations over 8 months were included. Median operator dose (OpD) was 12 µSv (range 0-930) and indexed to K and DAP to correct for patient factors and case times. Indexed OpD decreased significantly with each additional shield used (14.8 vs. 1.3 nSv µGy-1 m-2 and 124 vs. 14 nSv mGy-1 with one and four shields, respectively, p < 0.001). This trend was not significant with operator at head-of-bed. Combinations that included the ceiling shield had the lowest indexed OpD. The patient drape did not further reduce OpD when all other shields were used (1.3 vs. 2.2 nSv µGy-1 m-2, p = 0.5; 14 vs. 17 nSv mGy-1, p = 0.4) and was associated with higher patient exposure indexed to weight and fluoroscopy time (4.5 vs. 3.1 µGy m2 kg-min-1, p = 0.009; and 0.51 vs. 0.38 mGy kg-min-1, p = 0.01). Supplemental radiation barriers can decrease operator-absorbed radiation. A ceiling-mounted shield may provide greatest benefit. The authors do not recommend routine use of disposable patient drapes.