Background: Contrast induced nephropathy [CIN], because of its delay in onset, is often not clinically appreciated. While delayed assessment of renal function may show substantial recovery of renal function, episodes of CIN contribute to further deterioration of renal function. Angioplasty is currently predominately performed “ad hoc”, with the anatomy defined at the time of the procedure, increasing the contrast load. Concerns have also increased with the routine Emergency Room use of “triple rule out” contrast CTA (coronary obstruction, aorta dissection, pulmonary embolism) for chest pain, shortened stays and a reduction in “unnecessary” post procedure testing decreasing the detection and apparent incidence of CIN.
Objectives: Procedural management of patients undergoing Catheterization [Cath] and Angioplasty was analyzed using Failure Modes and Effects Analysis [FMEA] and Mehran’s formula for predicting risk of CIN and weighting of risk factors to predict severity. The likelihood of occurrence and detection were derived from the cohort of patients undergoing Cath at Stony Brook University Hospital. For patients undergoing Cath preprocedural concerns included; preop hemodynamic assessment, unknown baselines (renal function, hematocrit), diabetes mellitus, inadequate hydration, estimation of maximum contrast load to avoid CIN, avoidance of nephrotoxic agents. Procedural concerns included: contrast type and volume, hydration/ end organ perfusion, use of IABP, unnecessary procedures/potential staging. Post procedural concerns included: adequacy of hydration, follow-up monitoring of renal function.
Results: Procedural analysis reveals multiple opportunities for intervention to decrease the likelihood of CIN. The interventions most likely to improve the risk of CIN were identified as adequacy of hydration and limitation of contrast administration. Follow-up monitoring of renal function, with involvement of nephrology for management if indicated, was also deemed critical. Changes to the preprocedural order set in the EMR have been proposed to decrease the NPO interval, propose default hydration, suggest holding nephrotoxic drugs, provide an estimated maximal contrast volume. The ACIST injector will be reset to provide lower default contrast delivery. Education of physicians and staff to monitor and limit contrast use as possible is also underway.
Conclusions: The risk of CIN can be lessened by appropriate recognition and treatment. FMEA in conjunction with the Mehran CIN prediction formula provides an effective means of identifying procedural concerns that can be appropriately targeted in the Cath Lab.