Abstract: Objective To analyze the clinical value of carboxymethyl chitosan rinse in preventing systemic inflammatory response syndrome（SIRS）and bacteriuria after ureteroscopic lithotripsy（FURL）.Methods A total of 200 patients with urinary tract calculi from December 2016 to June 2018 were enrolled in this study.They were treated with FURL.They were randomly divided into control group and observation group，100 cases each.The control group was washed with normal saline during operation.The observation group was rinsed with a carboxymethyl chitosan rinse.Serum CRP levels，WBC counts，and neutrophil percentages were compared before and 2h and 24h after surgery.The incidence of SIRS and bacteriuria in the two groups was compared.Results The serum CRP level，WBC count and neutrophil percentage in the observation group were significantly lower than those in the control group at 2h and 24h after operation.The difference was statistically significant.The percentage of neutrophils at 2h after surgery in the observation group and control group was （81.12±9.96）% and（88.56±14.17）%，respectively；CRP at 24h after surgery was （5.07 ± 2.25） mg/L and（9.93±3.41） mg/L，respectively；WBC counts at 24h after surgery was （8.94± 2.77）×10⁹/L and（10.31 ± 3.30）×10⁹/L，respectively；The percentage of neutrophils at 2h after surgery at 24h after surgery was （77.32±10.43）% and（82.12±7.57）%，respectively（P＜0.05）.The incidence rates of SIRS and bacteriuria in the observation group were 2.0% and 4.0%，while in control group was 14.0% and 16.0%.The difference between the two groups was statistically significant（P＜0.05）.Conclusion Carboxymethyl chitosan rinsing solution can effectively prevent SIRS and bacteriuria after FURL，and it has good safety and effectiveness.

Key words: carboxymethyl chitosan rinse, flexible ureteroscopic lithotripsy, systemic inflammatory response syndrome, bacteriuria