Contrast-Induced Nephropathy and Oxygen Pretreatment in Patients With Impaired Renal Function

Abstract

Introduction: Contrast-induced nephropathy is a complication following coronary angiography and percutaneous coronary intervention. Because contrast-induced nephropathy is a predictor of long-term mortality in patients with ischemic heart disease undergoing percutaneous coronary intervention, preventive strategies are required. We assessed the effects of periprocedural oxygenation on contrast-induced nephropathy among patients with pre-existing renal dysfunction.

Methods: A total of 200 consecutive patients with impaired renal function (estimated glomerular filtration < 60 ml/min per 1.73 m²) undergoing elective cardiovascular angiography were randomly assigned to an oxygenation treatment (n = 100) or control group (n = 100). In oxygenation treatment, pure oxygen (2 L/min) was administered for 10 minutes before exposure to contrast medium. The primary endpoint was the incidence of contrast-induced nephropathy, defined as a ≥ 25% increase in serum creatinine levels from baseline within 48 hours of exposure.

Results: In the oxygenation treatment group, partial pressure of arterial oxygen was higher (135 ± 25 mm Hg vs. 84 ± 10 mm Hg, P < 0.001); contrast-induced nephropathy incidence was lower (1% vs. 8%, odds ratio [OR] = 0.12, 95% confidence interval [CI] = 0.01-0.95, P = 0.02); and partial pressure of arterial carbon dioxide and bicarbonate base lactate levels were similar compared with those in the control group. Upon univariate analysis, excess and absence of oxygenation treatment (OR = 9.18, CI = 1.13-74.86, P = 0.03) and anemia (OR = 4.30, CI = 1.04-17.78, P = 0.04) were shown to be associated with contrast-induced nephropathy incidence.

Conclusion: Oxygenation, a simple, nonpharmacological strategy, may be beneficial when using contrast media in patients with impaired renal function from noninvasive angiography to emergency catheterization.

Keywords: acute kidney injury; cardiovascular disease; chronic kidney disease; hypoxia; nephrotoxicity.

Figure 1

(a) Contrast-induced nephropathy (CIN) incidence between study groups. CIN incidence was significantly lower in the oxygenation treatment group than in the control group (1/100 [1%] vs. 8/100 [8%], odds ratio = 0.12, 95% confidence interval = 0.01–0.95, P = 0.02). (b) Changes in serum creatinine levels following contrast exposure. Postprocedural serum creatinine levels increased in the control group (1.08 ± 0.25 mg/dl to 1.15 ± 0.31 mg/dl, P = 0.04) but remained unchanged in the oxygenation treatment group (1.08 ± 0.21 mg/dl to 1.07 ± 0.19 mg/dl, P = 0.714). (c) Median and interquartile range of serum creatinine levels before and after cardiovascular angiography. The average change in serum creatinine levels was significantly lower in the oxygenation treatment group than in the control group (−0.01 ± 0.12 mg/dl vs. 0.07 ± 0.24 mg/dl, P < 0.001). Data are presented as mean ± SD. NS, not significant.