Relationship between composite hydration volume （Intravenous plus oral） and contrast-induced nephropathy after emergent percutaneous coronary intervention

Background Few studies have investigated the safe limits of total intravenous plus oral hydration to prevent contrast-induced nephropathy （CIN）. The present study was conducted to evaluate the effects of different composite hydration rate （intravenous plus oral） on CIN prevention in patients undergoing emergent percutaneous coronary intervention （PCI）. Methods This was a retrospective observational study that included 307 eligible patients, who were stratified into quartiles of rate of the composite hydration volumn to body weight and time （HV/ W/T）. CIN was defined as an absolute≥0.5 mg/dL or a relative ≥25% increase in the serum creatinine level within 72 hours after the procedure. Results In terms of risks of CIN, there were no statistical differences among individuals in four groups with different composite HV/W/T （27.6%, 19.0%, 23.0%, and 26.9% respectively in quartiles Q1, Q2, Q3, and Q4, P=0.565）. Additionally, higher composite hydration ratio seemed not to decrease the risk of in-hospital death, worsening heart failure and stroke （all P〉0.05）. After adjusting for other risk factors, multivariate analysis showed no statistical difference between Q2, Q3 or Q4, compared with Q1 （Q2 vs. QI： adjusted odds ratio [OR], 0.67, P=0.383; Q3 vs QI： adjusted OR, 0.77, P=0.550; Q4 vs. QI： adjusted OR, 0.75, P= 0.489）. Conclusion Excessive composite hydration may not provide supplemental benefit of CIN prevention and in-hospital outcomes in patients following emergent PCI, and moderate and prophylactic hydration is warranted.