Proposed Topic (Most preferred): :
Clinical Safety and Quality Service I (Projects aiming to improve efficiency and effectiveness of care delivery to meet international standards)
Proposed Topic (Second preferred): :
Clinical Safety and Quality Service II (Projects aiming to enhance clinical safety and outcomes, clinical governance / risk management)
Authors (including presenting author) :
Li PM(1), Chen HS(1), Ng TM(2), Lam TP(2)
Affiliation :
(1) Department of Paediatrics and Adolescent Medicine (Cardiology), Hong Kong Children’s Hospital (2) Department of Radiology, Hong Kong Children’s Hospital
Introduction :
The detrimental effects of ionizing radiation exposure during cardiac catheterization are always of concern to paediatric patients with congenital heart diseases as they may require long and repetitive procedures. In Dec 2017, the first phase of radiation reduction exercise based on the principle of “ALARA” (as low as reasonably achievable) was initiated in the Paediatric Cardiac Catheterization Laboratory (PCCL) at Queen Mary’s Hospital (QMH), which mainly involving the reduction of frame rate. Since the translocation of paediatric cardiology service to Hong Kong Children’s Hospital (HKCH) in October 2020, the second phase of radiation reduction exercise has commenced at the Hybrid Cardiac Catheterization Laboratory (HCL). Under this phase, based on the "ALARA" principle, the measures including further reduction of the frame rate and dose, removal of the anti-scatter grid with air-gap technique (AGT) for the patients with <20kg of body weight were taken in practice.
Objectives :
To assess the effectiveness of radiation dose reduction in the second phase of radiation reduction exercise.
Methodology :
Subjects were patients aged <18 years old in the procedures of transcatheter closure of (1) patent ductus arteriosus (PDA) and (2) atrial septal defect (ASD) in QMH PCCL (2017-2019) and HKCH HCL (2020-2023). Outcomes were measured by comparisons of dose area products (DAP) between two phases.
Result & Outcome :
All censored procedures were successfully performed. Total 33 and 62 patients had undergone the transcatheter closures of PDA in QMH PCCL (2017-2019) and HKCH HCL (2020-2023) respectively. The mean of DAP was decreased from 7.62 ± 5.42 Gycm² in QMH PCCL to 2.06 ± 1.95 Gycm² in HKCH HCL (p<0.001). Regarding the procedure of transcatheter closure of ASD, there were 31 patients in QMH PCCL and 55 patients in HKCH HCL recruited. The mean of DAP was greatly reduced from 22.34 ± 19.10 Gycm² in QMH PCCL to 5.94 ± 12.24 Gycm² in HKCH HCL (p<0.001). The image quality had not been downgraded and there was no significant difference in the procedural time after the reduction of frame rate and with the use of AGT.
Conclusion: The enact of the radiation reduction exercise with the principle of “ALARA” and the air-gap technique markedly reduced the radiation exposure in the procedures of transcatheter closure of PDA and ASD on patients aged <18 years old.
