Background: Several alternative prevention strategies are being employed in various clinical settings to reduce Contrast-induced nephropathy (CIN). Despite the proposed theoretical advantage of these strategies, there is no agreement on their relative effectiveness in real practice. This study aimed to estimate the incidence of CIN and to report on the real effectiveness of sodium bicarbonate to protect the kidney from CIN in various cardiac patients undergoing cardiac catheterization.

Methods: This is a retrospective, single-center, cohort study. A total of 60 patients admitted between January 2016 and November 2021 who were undergoing coronary angiography at a single Saudi center were included.  All patients received either intravenous sodium bicarbonate or normal saline hydration prior to, during, and after the implementation of CM.  CIN was defined as serum creatinine (SCr) ≥ 25% or ≥ 0.5 mg/dL compared to the baseline value within 48 h after CM exposure.

Results: Among all patients, the incidence of CIN at 24 and 48 h was 16.7% and 15%, respectively. Strikingly, the incidence of CIN at both time points was significantly higher among patients who received sodium bicarbonate than among those who received normal saline hydration only [30% vs. 3.6% (P=0.012) and 38% vs. 3.3% (P=0.002), respectively].  Dyslipidemia status was the most positive predictor of CIN incidence at both time points.

Conclusions: The 16.7% incidence of CIN in this sample is considered very high compared to the rates in previous national and international studies.  This finding indicated that further preventive measures should be urgently initiated with strict protocols for the implementation of CM according to updated guidelines.

Keywords: Contrast-induced nephropathy; Sodium bicarbonate; Normal saline