Preventive Efficacy of Oxygenation on Contrast-Associated Acute Kidney Injury in Chronic Kidney Disease (stages 3-5) Patients Undergoing Elective Coronary Angiography ± Revascularisation: An Open Label Bicentric Randomised Controlled Trial.

Contrast-associated acute kidney injury (CA-AKI) has higher mortality in coronary artery disease (CAD) with chronic kidney disease (CKD), undergoing coronary angiography ± revascularisation (CAG ± R). We conducted a clinical superiority trial with dichotomous outcomes to evaluate the impact of renal hypoxia mitigation with oxygen therapy (OT) on CA-AKI incidence. CKD stages 3-5 patients undergoing CAG ± R were assigned to the OT group (OTG) and the control therapy group (CTG). CTG received hydration only, whereas OTG received 2 L/min of pure oxygen in addition to hydration. The primary endpoint was the incidence of CA-AKI at 48 h. Secondary endpoints included patient and renal survival (doubling of serum creatinine or dialysis dependency) at 30 days, as well as intervention complications. Of the 395 patients, 321 patients qualified for the per-protocol analysis (OTG: 160 and CTG: 161). CA-AKI incidence was 5.6%, and OTG observed an effective prevention (1.25% vs. 9.93%, CTG, p = 0.004). Renal and patient survival at 30 days was 100%. Three CTG patients required dialysis and were dialysis-independent at 30 days. The risk of CA-AKI incidence was high among ages > 65 years (p = 0.007), previous acute myocardial infarction (p = 0.02), CKD stage-3 (p = 0.01) and avoidance of OT use (p = 0.02). OTG had a favourable serum creatinine trend (p = 0.05). Absolute risk reduction of CA-AKI with OT was 8.7%, and the number needed to treat was 12. Interventional complications were zero. Oxygen supplementation and saline hydration effectively prevented CA-AKI in CKD stages 3-5 patients undergoing elective CAG ± R. Hence, oxygen therapy should be a standard CA-AKI protective strategy during CAG ± R and radiocontrast-related procedures.