Use of a dose-dependent follow-up protocol and mechanisms to reduce patients and staff radiation exposure in congenital and structural interventions.

BACKGROUND

Increasingly complex structural/congenital cardiac interventions require efforts at reducing patient/staff radiation exposure. Standard follow-up protocols are often inadequate in detecting all patients that may have sustained radiation burns.

METHODS

Single-center retrospective chart review divided into four intervals. Phase 1 (07/07-06/08, 413 procedures (proc)): follow-up based on fluoroscopy time only; frame rate for digital acquisition (DA) 30 fps, and fluoroscopy (FL) 30 fps. Dose-based follow-up was used for phase 2-4. Phase 2 (07/08-08/09, 458 proc): DA: 30 fps, FL: 15 fps. Phase 3 (09/09-06/10, 350 proc): DA: 15-30 fps, FL: 15 fps, use of added radiation protection drape. Phase 4 (07/10-10/10, 89 proc): DA: 15-30 fps, FL: 15 fps, superior noise reduction filter (SNRF) with high-quality fluoro-record capabilities.

RESULTS

There was a significant reduction in the median cumulative air kerma between the four study periods (710 mGy vs. 566 mGy vs. 498 mGy vs. 241 mGy, P < 0.001), even though the overall fluoroscopy times remained very similar (25 min vs. 26 min vs. 26 min vs. 23 min, P = 0.957). There was a trend towards lower physician radiation exposure over the four study periods (137 mrem vs. 126 mrem vs. 108 mrem vs. 59 mrem, P = 0.15). Fifteen patients with radiation burns were identified during the study period. When changing to a dose-based follow-up protocol (phase 1 vs. phase 2), there was a significant increase in the incidence of detected radiation burns (0.5% vs. 2%, P = 0.04).

CONCLUSIONS

Dose-based follow-up protocols are superior in detecting radiation burns when compared to fluoroscopy time-based protocols. Frame rate reduction of fluoroscopy and cine acquisition and use of modified imaging equipment can achieve a significant reduction to patient/staff exposure.