Clinical Study on Disposable Sterile Urinary Catheter

Inclusion Criteria: * 18-80 year old patients; * Retained catheter ≥ 7 days; * Patients who were conscious and had good communication skills and volunteered to participate in the study. Exclusion Criteria: * Pregnant and lactating female patients; * Diabetes patients; * Patients allergic to sulfadiazine, silica gel and stainless steel; * Urethral malformation, acute urethral injury, prostate disease, intermittent catheterization, suprapubic cystostomy and other patients who are not suitable for catheterization; * Patients who have used urinary catheters for a long time or had catheters retained within one week; * Patients who are participating in other clinical trials that interfere with this trial.