Study limitations
pre-PCI, renal insufficiency
RENAL INSUFFICIENCY
Despite the precise randomization, which results in an unimportance difference in baseline characteristics of the two groups, our study has several limitations. First, although our study had a relatively large sample size, the single-center study was also a limitation. Second, although many potential interfering covariables were adjusted by our models, we cannot rule out residual confounding factors or potential selection bias. Third, creatinine as the CA-AKI diagnostic indicator is insensitive, the pre-PCI serum creatinine levels may not be the real baseline serum creatinine level because of possible unstable clinical situations. However, our definition of CA-AKI is dependent on serum creatinine, which is an incomplete marker for kidney function. Fourth, few patients with renal insufficiency were included (56/438), this will affect the modified hydration effect.