All the cases were selected from hemodialysis patients using TCC in our center from 2013 to 2017. There were a total of 434 cases, aged from 6 to 93 years old. The primary diseases were hypertensive nephropathy, diabetic nephropathy, chronic glomerulonephritis, cystic nephropathy, obstructive nephropathy and so on. The TCC detention period was from 2 months to 7 years. Catheterization was performed in 426 cases of the right internal jugular vein, 7 cases of the left internal jugular vein and 1 case of the right femoral vein. Hemodialysis was performed three times a week for 4 hours each time.

The basic information of the 434 patients was as follows: 217 males and 217 females, with an average age of 61.47 ± 16.56. The original diseases - there were 141 cases of hypertensive nephropathy (32.5%), 105 cases of diabetic nephropathy (24.2%), 56 cases of chronic glomerulonephritis (12.9%), 27 cases of cystic nephropathy (6.2%), 63 cases of obstructive nephropathy (14.5%), 13 cases of nephrotic syndrome (3.0%), 4 cases of acute kidney injury (0.9%), and 25 cases of other primary diseases (5.8%). The average catheter detention days were 180 ± 325.077. See Table 1.

1) Catheter outlet infection: infection within 2 cm of catheter outlet. 2) Duct tunnel infection: Infection within the subcutaneous tunnel of the catheter more than 2 cm away from the outlet. 3) Catheter related blood stream infection

Note: *Others include drug-induced renal damage, membranous nephropathy, multiple myeloma, lupus nephritis, hemolytic uremic syndrome, ANCA-associated vasculitis, hepatitis b-associated nephritis, and purpura nephritis.

(CRBSI): Bacteremia or septicemia caused by a partial infection in the lumen or blood vessel that spreads into the blood stream [6].

1) The internationally accepted 1000-day rate of infection was calculated as = infection cases/catheter days × 1000. 2) The catheter infection rate was calculated by comparing the number of infections with the total number of patients = infections/patients ×100.

Application of Quality of Nursing Index Management

1) The quality index management was implemented in the first quarter of 2014, and establishment of a Quality Management Team, with the head nurse as the group leader and the nursing core staff as the team members. TCC experts in the group are responsible for statistics and analysis of infection rates in 2013.

2) TCC registration forms were developed from 2014. The nurses in each shift recorded and transferred the abnormal situation of TCC in the shift. The TCC specialist executed timely integrated medical checking to TCC infection cases. They developed and implemented treatment and nursing plan together. TCC specialist collected data every quarter, controlled the nursing quality of the TCC, analyzed the problems existing in the record, and found out the root cause of the infection (from people, machine, material, method or checking). The specialist would also personalize solutions to problems, train the nurse how to solve common problems, optimize the procedure and supervise the implementation.

3) Studies have shown that catheter infection is related to catheter interface contamination, skin bacterial transitional contamination of puncture site, hemoperfusion contamination, catheter material, bacterial biofilm, internal characteristics of pathogens and other factors [7] [8]. Studies have shown that cluster nursing can effectively reduce the incidence of catheter infection [9]. Since 2014, our department has continuously revised and optimized the guidelines for catheter opening and sealing and catheter dressing change, implemented personalized dressing change procedures for patients with different conditions, bound them into books and organized medical staff in the department to conduct training and learning.

4) For TCC patients, guidance was offered to them on infect control at home. They could choose to wrap plastic wrap around the shoulder of the catheter during shower to cover the entire catheter or clean the covered area after shower or put the external part of the catheter into the anal bag, with the adhesive layer of the anal bag around the catheter mouth, remove the disposable anal bag after shower, and then re-fix the exposed part of the catheter in front of the chest wall. Lectures on catheter maintenance were given to patients no less than twice a year, and special guidance was given by the nurse in charge of each dialysis.

5) Training of nursing personnel: all the new and advanced nurses received the theoretical and operational training of dialysis catheter opening, dressing changing and sealing, and shall not conduct the above operations independently before passing the examination of operation and theory. Unnecessary opening times of catheter ports during dialysis were avoided. For poor catheter flow and reverse connection of arteriovenous ports, nurses were required to perform hand hygiene, wear sterile gloves to separate catheter and blood line catheter, and reduce exposure time of catheter ports. There would be blood scab formation at the thread of the catheter after the reverse connection. It was required that the nurse should use disinfectant gauze to clean the blood scab when getting off. After there was no blood scab left, the sterile disinfection process should be carried out. They had to put the sterile plug to protect the catheter port, preventing blood scabs from entering the catheter and reducing the risk of infection.

6) To find out the regularity or seasonality of TCC infection. From statistical records, we found that each year in the 3rd quarter TCC infection rate had a rising trend. Through the integration of medical ward inspection, analysis and discussion, we found that the third quarter in Guangzhou (7 September) was usually hot and the stay-home patients would easily sweat. Guangzhou people like to take shower, and the catheter dressing exposed to water. We selected different dressings for different patients. For patients with a certain level of knowledge and good learning ability, we guided them to change the dressing for the catheter at home, and the catheter infection was better controlled.

7) Nursing quality indicator management not implemented in 2013. Accordingly, following the implementation of improvement measures in 2014, The TCC infection rate in 2013 was used as the baseline data and compared with the annual TCC infection rate from 2014 to 2017. From 2013, pairwise compari­son was conducted for the infection rate every two years. TCC experts are responsible for this statistical work.

SPSS 23.0 Software was used for statistical analysis of the data, and the counting data were expressed as rate. X² test was used, and P < 0.05 was considered as statistically significant.

From 2013 to 2017, there were 60 cases of catheterization infection in TCC patients, among which pathogenic bacteria were detected in 13 patients, with a positive detection rate of 21.67%. Among them, there were 5 cases of Staphylococcus aureus, 1 case of staphylococcus epidermidis, 1 case of gram-positive cocci, 1 case of staphylococcus vorchii, 1 case of acinetobacter baumannii, 1 case of colorobacillus denitrifying, 1 case of sarrella mucilis, 1 case of staphylococcus cephalus and 1 case of pseudomonas aeruginosa. This result is similar as the report of Yuhong Pang and Jun Wang et al. in China, as well as the reports abroad [10] [11] [12]. Staphylococcus aureus remains the most common infectious pathogen.

The number of TCC patients and indwelling catheter days increased year by year from 2013 to 2017, while the total infection rate decreased, as shown in Table 2. As shown in Table 2, after comparison, the infection rate of TCC showed a decreasing trend (X² = 11.34, P = 0.023). From 2013, pairwise comparison was conducted for the infection rate every two years. The comparison between 2013 and 2014 (X² = 4.20, P = 0.04) was P < 0.05, which was statistically significant. Compare the other years in pairs. The comparison between 2014 and 2015 (X² = 0.00, P = 0.10), 2015 and 2016 (X² = 0.03, P = 0.85), 2016 and 2017 (X² = 1.35, P = 0.25) result was P > 0.05, which was not statistically significant.