Assessing the impact of renal impairment on outcome after arterial intervention: a prospective review of 1,559 patients.

Abstract

To investigate the impact of pre and peri-operative renal impairment on outcome, and the need for renal replacement therapy, in a multicenter study of patients undergoing a variety of surgical and radiological arterial procedures. A six month prospective multi-centre study of 1,559 consecutive patients undergoing arterial interventions was performed. The primary outcome measures were the development of renal impairment, 30 day mortality and the need for renal replacement therapy. CRI was defined as an admission serum Creatinine>125 micromol/l. ARI was defined as a rise in serum Creatinine of >50% above pre-operative levels, excluding patients in whom the post operative level remained <125 micromol/l. A multivariate logistic regression model was constructed to identify independent risk factors for the development of ARI and mortality. There was a significantly increased 30 day mortality in those patients who developed ARI (29/90 - 32%) or who had CRI (43/269 - 16%) when compared with those whose creatinine remained normal throughout (44/1200 - 4%) (p<0.0001 - Chi-square test). One thousand two hundred and ninety patients had normal pre operative renal function and 269 patients had CRI. Seven percent (90/1290) of the patients with normal pre-operative creatinine developed ARI. Operation type, emergency presentation, and chronic renal impairment were independent predictors of both acute renal impairment (p<0.01) and mortality (p<0.001). Sixteen patients (1%) required temporary haemofiltration (in 9 patients this developed in the context of multiple organ failure) with only 1 requiring long term support. Eleven of these patients died (30 day mortality 69%). Renal failure following arterial intervention is associated with significant mortality. Renal replacement therapy is necessary mainly in the setting of multiple organ failure on intensive care units with few patients surviving to require long term renal replacement therapy. The identification of the 'at risk' patient is most strongly associated with age, raised preoperative creatinine, emergency procedures and thoraco-abdominal aneurysm.