It’s Jeff Kline Week at EMLitOfNote, with the second Carolinas paper this week – and, as a Patient Safety and Quality Fellow, I just can’t help but cite articles that deal with the consequences of otherwise well-meaning practice.
This small study followed 174 patients undergoing CTPA demonstrated a yield of 7% for PE. On the other hand, this same cohort demonstrated a yield of 14% for contrast-induced nephropathy – as defined by an increase in serum Cr of 0.5 mg/dL or >25%. Three of the 24 patients with CIN progressed to severe renal failure, two of whom died. The proportion of CIN and renal failure were similar to the outcomes observed in the additional 459 patients they followed for CT imaging on other contrast protocols.
So, the rate of CIN is not insignificant – particularly compared to the rate of diagnosis of PE at this institution. It seems to be suggested by this study, although not shown, that the relative risk of death conferred by receiving contrast and developing CIN might even exceed the number of adverse events that might have occurred from PE if left undiagnosed or untreated.
“Prospective Study of the Incidence of Contrast-induced Nephropathy Among Patients Evaluated for Pulmonary Embolism by Contrast-enhanced Computed Tomography”
http://www.ncbi.nlm.nih.gov/pubmed/22687176