PURPOSE: Intravenous contrast enhanced imaging enhances the detection of pathology in critical illness. Given the risk of contrast nephropathy associated with iodinated CT contrast, alternate contrast modalities need to be examined, particularly in the setting of renal insufficiency. The purpose of this study was to examine the renal safety of MRI with gadolinium in critically ill patients.
METHODS: The study involved a retrospective analysis of 153 ICU patients at a single academic center during 2007, who received an MRI imaging study with gadolinium in the absence of renal replacement therapy. For each case, a serum creatinine and estimated GFR (as calculated by the MDRD equation) were recorded prior to, and 48 and 72 hours after the MRI. The serum creatinine and estimated GFR (eGFR) values before and after the MRI were compared for each case. In addition, the cases were analyzed for sub-acute complications of nephrogenic systemic fibrosis (NSF), a known complication of gadolinium in end stage renal disease.
RESULTS: The age of the patients ranged from 19 to 97 years, with 49% being female. The pre- MRI serum creatinine values ranged from 0.4 to 4.8 mg/dl, with 39 cases (25%) having values ≥ 1.5 mg/dl and corresponding eGFRs < 60 ml/min. A comparison of the pre and post MRI serum creatinine and eGFR values demonstrated no statistically significant difference (P< 0.05), including those cases with a pre MRI serum creatinine> 1.5 mg/ dl. In addition, no cases of NSF were noted.
CONCLUSION: These observations suggest that MRI with gadolinium is a non-nephrotoxic imaging modality in critically ill patients. Importantly, the renal safety of this modality extends to cases of renal insufficiency, where contrast enhanced CT may be contraindicated due to the risk of CT contrast nephropathy.
CLINICAL IMPLICATIONS: These findings suggest that MRI with gadolinium can be a useful contrast enhanced imaging modality in critical care, especially in the setting of renal insufficiency.
DISCLOSURE: Nicole Harlan, No Financial Disclosure Information; No Product/Research Disclosure Information