Abstract 1056: Does “Safe” Dosing of Iodinated Contrast Prevent Contrast-Induced Acute Kidney Injury?
Background: Previous work on contrast-induced acute kidney injury (CI-AKI) has identified contrast volume as a risk factor and suggested there is a maximum allowable contrast dose (MACD) above which the risk of CI-AKI is markedly increased; however, little research has been done to validate this 20-year old equation with current contrast agents or categories of risk above the MACD limit. We hypothesized that the relationship between contrast volume and CI-AKI might be linear and there might be reason to track incremental contrast volumes above the MACD limit.
Methods: Consecutive patients undergoing PCI were prospectively enrolled from 2000 –2008 (N=10,065). MACD was defined as (5 mL × body weight (kg))/baseline serum creatinine (mg/dL)) and divided into categories where 1.0 reflects the MACD limit: ≤MACD ratios (2.0). CI-AKI was defined as a ≥0.3 (mg/dL) or ≥50% increase in serum creatinine from baseline or new dialysis. Multivariable regression was conducted to evaluate the effect of exceeding the MACD on CI-AKI.
Results: 20% of patients exceeded the MACD. Risk-adjusted CI-AKI increased by an average of 45% for each category exceeding the MACD (OR: 1.45; 95%CI: 1.29 –1.62). Adjusted odds ratios (OR) for each category exceeding the MACD were 1.60 (95%CI: 1.29 –1.97), 2.02 (95%CI: 1.45–2.81), and 2.94 (95%CI: 1.93– 4.48). CI-AKI for contrast dose <MACD showed no difference (p=0.5).
Conclusions: The relationship between contrast volume and CI-AKI is linear and incremental use of contrast beyond the MACD increases the risk CI-AKI. Interventionalists should consider this when making procedural decisions that will require ever-higher contrast volumes.