Objectives : To evaluate the difference in the renal protective effects of allopurinol and n-acetyl cysteine along with saline hydration in patients of contrast induced nephropathy (CIN) post cardiac interventions.
Background: CIN remains a common complication of cardiac procedures. Radio contrast agents can cause a reduction in renal function that may be related to oxidative stress underlining various patho- physiologies. Conflicting evidence suggests that administration of allopurinol, a xanthine oxidase inhibitor can prevent CIN.
Materials and methods: This is a study of 500 patients undergoing angiography and coronary revascularisation in patients showing significant coronary block. The angiography positive patients (275) were prospectively randomised to different treatment protocol to study for their reno-protective effect. The patients received either of the three drugs saline hydration (SH, 1ml/kg/hr), n-acetylcysteine (SH+NAC, 600 mg bd) or Allopurinol (SH+ALLP, 300 mg/day) 12 hours before and after administration of radio contrast agent. Levels of serum creatinine and blood urea of the 275 patients recorded at 24 hour interval were noted post angioplasty over a course of 5 days in patients receiving either omnipaque (125) or visipaque (150) contrast media. All the 500 patients were also assessed for development of any kind of adverse drug effects/reactions with the two contrast media.
Results: CIN occurred in 56 of 500 the patients (10.6%) who underwent angiography and 49 of 275 patients (17.8%) who underwent angioplasty. In the omnipaque group CIN occurred in 16/40, 8/40, nil/45 in patients receiving SH, NAC plus SH and SH plus ALLP respectively. In the visipaque group CIN occurred in 15/50, 10/50, nil/50 in the three treatments groups respectively. Allopurinol maintained a consistent fall in the serum creatinine & blood urea levels from the baseline values from the end of the 1(st) day (p < .01 & .001) in both the category. Visipaque proved to be better dye than omnipaque with less adverse drug effects/ reactions.
Conclusion: Prophylactic oral administration of allopurinol (300 mg/day) along with hydration is better than n-acetylcysteine and saline hydration alone for protection against CIN in patients undergoing coronary procedures.
Keywords: Allopurinol; Contrast nephropathy; Omnipaque; Percutaneous coronary interventions; Visipaque.