Contrast nephropathy in lower limb angiography

Aim: This study examines the occurrence of contrast nephropathy in a series of 302 consecutive lower limb angiogram and angioplasty procedures. Methods: Serum creatinine measurements, 1 and 3 days after the procedures, were used to identify cases of contrast nephropathy, defined as a 25% increase above initial creatinine. These cases were reviewed retrospectively. A total of 267 patients had 224 diagnostic, and 78 interventional lower limb angiographic procedures. Of these, 46% had pre-existing renal impairment (creatinine >118 mumol/l), of whom 11% were on dialysis - dialysis patients were excluded from analysis of changes in creatinine. Repeat creatinine measurements were taken after 191 procedures. Results: Contrast nephropathy occurred after 15 procedures: of whom 9 died, and 6 recovered. Of these patients, 11 were taking potentially nephrotoxic drugs and 9 had renal impairment. Precautions to avoid contrast nephropathy were taken in only 2 cases. Of the 9 deaths, 6 were associated with severe underlying disease processes, but 3 occurred directly as a result of contrast nephropathy. Contrast nephropathy has an incidence of 8% in this series: the incidence in acute limb-threatening ischaemia is double that for other cases. Death from renal failure is relatively rare, with an incidence of 1%. In uncomplicated angiography or angioplasty, where admission is not prolonged by a need for further treatment, the condition has no mortality. Conclusions: Accepted precautionary measures should be observed, and alternatives to conventional angiography should be considered - particularly where there is pre-existing renal impairment and other co-morbidity.