Prevention of central line-associated bloodstream infections: a survey of ICU nurses’ knowledge and practice in China

Background Central line-associated bloodstream infections (CLABSI) are largely preventable when evidence-based guidelines are followed. However, it is not clear how well these guidelines are followed in intensive care units (ICUs) in China. This study aimed to evaluate Chinese ICU nurses’ knowledge and practice of evidence-based guidelines for prevention of CLABSIs issued by the Centers for Disease Control and Prevention, US and the Department of Health UK. Method Nurses completed online questionnaires regarding their knowledge and practice of evidence-based guidelines for the prevention of CLABSIs from June to July 2019. The questionnaire consisted of 11 questions, and a score of 1 was given for a correct answer (total score = 0–11). Results A total of 835 ICU nurses from at least 104 hospitals completed the questionnaires, and 777 were from hospitals in Guangdong Province. The mean score of 11 questions related to evidence-based guidelines for preventing CLABSIs was 4.02. Individual total scores were significantly associated with sex, length of time as an ICU nurse, educational level, professional title, establishment, hospital grade, and incidence of CLABSIs at the participant’s ICU. Importantly, only 43% of nurses reported always using maximum barrier precautions, 14% of nurses reported never using 2% chlorhexidine gluconate for antisepsis at the insertion site, only 40% reported prompt removal of the catheter when it was no longer necessary, and 33% reported frequently and routinely changing catheters even if there was no suspicion of a CLABSI. Conclusion Chinese ICU nurses in Guangdong Province lack of knowledge and practice of evidence-based guidelines for the prevention of CLABSIs. National health administrations should adopt policies to train ICU nurses to prevent CLABSIs.


Background
Central line-associated bloodstream infections (CLAB-SIs) are the most common complication of central venous catheters (CVCs), with an incidence of 4.1 per 1000 central line days [1]. CLABSIs are associated with increased morbidity, mortality, and medical costs [2]. A meta-analysis shows that patients with CLABSI have an 2.75-time higher risk for hospital death than those without CLABSI [3]. It has been shown that CLABSI is associated with high-cost burden, accounting for approximately $46,000 per case [4]. CLABSIs are considered to be largely preventable when evidence-based guidelines for the insertion and maintenance of CVCs are followed [5], such as hand washing, using full-barrier precautions during central venous catheter insertion, cleaning the skin with chlorhexidine, and removing unnecessary catheters.

Open Access
*Correspondence: 327240463@qq.com 1 School of Nursing, Guangdong Medical University, No. 1 Xincheng Road, Songshan Lake Science and Technology Industrial Park, Dongguan 523808, Guangdong, China Full list of author information is available at the end of the article Most intensive care units (ICUs) in developed countries now report CLABSI rates of zero or close to zero [6]. However, the overall incidence of CLABSIs in ICUs in China is about 2.81‰ [7].
It has been confirmed that evidence-based interventions can reduce the incidence of CLABSIs [8], including nursing bundles coupled with education and the commitment of both staff and institutions. The Keystone ICU Evidence-Based Intervention Program initiated by the Michigan Health and Hospital Association (MHA) reduced the median incidence of CLABSIs from 2.7/1000 catheter days at baseline to zero in the first 3 months [5]. Ullman et al. [9] reported that the knowledge and practice for preventing CVC-related infections varied greatly in pediatric ICU nurses in Australia and New Zealand, and many were inconsistent with guideline recommendations, such as maximum sterile barrier precautions, use of suture-less securement devices, replacing transparent dressing at least every 7 days. The authors concluded that an overall improvement of knowledge of evidencebased guidelines was needed. Bianco et al. [10] reported that evidence-based policies and training can help nurses increase their knowledge, practice, and attitude towards preventing CLABSIs. The authors also reported that despite new evidence, many non-evidence-based practices continue.
A number of researchers have designed questionnaires to investigate ICU nurses' knowledge of guidelines to prevent CLABSIs [11][12][13][14]. Labeau et al. [8] developed and validated a questionnaire for evaluating critical care nurses' knowledge of evidence-based guidelines for preventing CVC infections. The questions in Labeau et al. 's questionnaire are very important and concise, and suitable for large-scale investigations. Studies performed in Poland, Australia, and other countries have referenced the questionnaire developed by Labeau et al. [9,15].
The CLABSI rate in ICUs in China (2.81‰ [7]) is greater than in most developed countries [6]. The purpose of this study was to use questionnaires to determine Chinese ICU nurses' knowledge of evidence-based guidelines for preventing CLABSIs issued by the Centers for Disease Control and Prevention, US [16] and the Department of Health UK [17], and their frequency of practicing guideline recommendations.

Study design and subjects
This was a cross-sectional descriptive survey study. It was conducted using an online tool, Questionnaire Star (https ://www.wjx.cn/wjx/desig n/previ ewmob ile. aspx?activ ity=41939 767&s=1). The study was conducted by respondent driven sampling (RDS) from June to July 2019. The selection criteria for the respondents were: (1) nurses worked in the hospital comprehensive ICU, in which patients used central venous catheters; (2) the nurses participated in the maintenance of central venous catheters.
There were three different sources of respondents. (1) Nurses from 6 hospitals with comprehensive ICUs were directly invited to participate in the study and complete the online questionnaire since we know the head nurse of ICU of these six hospitals. (2) Students who graduated from Guangdong Medical University were asked to send out invitations to nurses to complete the questionnaire.
(3) The information about the questionnaire was also distributed through the WeChat group of students who graduated from the Nursing College of Guangdong Medical University. Nurses were also asked to inform other ICU nurses about the study and ask them to complete the questionnaire. All respondents voluntarily participated in the survey, and the questionnaire was collected anonymously. Ethics approval for this study was obtained from the Ethics Committee, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China (Reference number: YJYS2018075). Completion and return of the questionnaires was considered consent and voluntary participation in this study.
The study was aimed at ICU nurses in Guangdong Province. However, after it was found that a few nurses from other provinces were completing the questionnaire, we set a limitation such that only IP addresses locating in Guangdong Province could access the online questionnaire.

Questionnaires and data collection
The questions in the questionnaire of this study were mainly based on the guidelines issued by the Centers for Disease Control and Prevention (CDC), U.S [16]. and the Department of Health UK [17]. The questionnaire used in this study was titled 'Knowledge of CLABSI Prevention Questionnaire' . It was based on the questionnaire developed by Labeau et al. [11], who authorized its modification and use in this study. The modifications were made based on several current literature references, and current evidence-based recommendations for the prevention of CLABSIs. The questionnaire consisted of 11 questions, and a score of 1 was given for a correct answer and a score of zero for a wrong answer (minimum total score = 0, maximum total score = 11).
The other questionnaire used in the study was titled 'Behavior questionnaire on prevention of CLABSI'. It was based on the questionnaire developed by Ullman et al. with some revisions [9]. The questionnaire consisted of closed-end questions investigating nurses' practices toward the prevention of CLABSIs. Answers were measured using a 5-point Likert-type scale, ranging from "never" to "always".

Internal consistency of questionnaire respondents
The Cronbach's alpha of the ICU Nurses' Knowledge of Evidence-Based CLABSI Prevention questionnaire was 0.903, and of the behavior questionnaire on prevention of CLABSI was 0.924. These results indicate that the questionnaire results exhibited good internal consistency.

Statistical analysis
No data was lost due to the use of online survey tools. Continuous variables were described as mean ± standard deviation (SD), or range (only for age). After evaluating the normality of the data distribution, the total scores were compared by the Student's independent t-test between two groups. For comparison among three or more groups, the one-way ANOVA was conducted with the Bonferroni post-hoc pairwise comparisons. Categorical data were presented as number and percentage (%), and compared with the chi-square test or Fisher's exact test (if any expected value ≤ 5 was found). The internal consistency of questionnaire respondents was assessed by Cronbach's alpha, which is also a reliability index. The statistical significance level for all tests was set at a 2-tailed P-value < 0.05. All analyses were performed using IBM SPSS version 25 software (IBM Corporation, Somers, New York).

Sample characteristics
The total number of visits to the questionnaires was 2607, and the number of nurses completing the questionnaires was 835. The overall questionnaire response rate was 835/2607 (32.03%). The characteristics of the 835 nurses who completed the questionnaires are summarized in Table 1. The mean age of all respondents was 26.54 years (range: 18-65 years). The nurses completing the questionnaires were from at least 104 hospitals, and 93% (777/835) of nurses were from hospitals in Guangdong Province. Workshops/courses were the primary method nurses obtained information on CLABSI prevention and 84.43% (705/835) of nurses indicated they needed more information about CLABSI.

Subgroup analyses of 'ICU Nurses' Knowledge of Evidence-Based CLABSI Prevention' results stratified by demographic and other variables
Results of the Subgroup analyses stratified by demographic and other variables are summarized in Table 3 and Fig. 1. The mean overall score for the 11 questions was 4.02. It was found that the total knowledge score was significantly different in all the subgroup analyses stratified by Sex, length of time of ICU nursing, educational level, nursing level,establishment of nurses,hospital grade, and incidence of CLABSI. Female nurses had significantly higher scores than male nurses (P < 0.001), and experienced nurses had higher scores than less experienced nurses (P < 0.001). There was significant difference among the groups of different length of ICU nursing (P = 0.001). A trend could be found that the longer a nurse worked in the ICU, the higher the questionnaire score. Nurses who graduated from undergraduate courses had significantly higher scores than those who graduated from junior and technical secondary schools (P < 0.001). Nursing level also affected questionnaire score: the scores of nurses were significantly lower than those of nurse practitioner and nurse-in-charge (P < 0.001).
In China, nurses can be divided into 3 categories: establishment nurses, personnel agent nurses, and contract nurses according to whether they have national establishment or not. Contract nurses scored significantly higher than establishment nurses and personnel agent nurses (P < 0.001). The incidence of CLABSI in the ICU was also associated with questionnaire score: nurses in ICUs with an incidence of 1-3‰ were significantly higher than nurses in ICUs with an incidence of < 1‰ and higher * Indicates the correct answer than that of nurses who answered "I don't know" (both, P < 0.05).

Results of the Behavior questionnaire on prevention of CLABSI
Results of the Behavior questionnaire on prevention of CLABSI of ICUs in China are summarized in Table 4. Approximately 43% (363/835) of nurses reported always using maximum barrier precautions, while around 15% (121/835) reported never using 2% chlorhexidine gluconate. Around 39% (323/835) of nurses reported replacing administration sets at least every 7 days, but no more frequently than at 96-h intervals. Around 33% (273/835) of nurses reported frequently and routinely changing catheters, even if there was no suspicion of a CLABSI.
Since the care of the catheter insertion site is usually a nursing responsibility, it would be expected that nurses would overall answer questions on this topic correctly. However, our results did not find this assumption true. Only 16% of nurses correctly answered that CVCs did not need to be replaced routinely at a set interval. Only approximately 11% (91/835) of nurses correctly answered that when continuous administration of liquids other than blood, blood products, or fat emulsions is performed, the drug delivery device should be replaced every 96 h. The rates of correct answers to these 2 questions were significantly lower than in other countries [9,11,15,22,23]. Furthermore, the overall correct answer rate of the ICU Nurses' Knowledge of Evidence-Based CLABSI Prevention Questionnaire was only 37%, which is also lower than the result (44.4%) of a knowledge test among 3405 European ICU nurses [11]. This indicates that a great deal of improvement of ICU nurses' knowledge of evidence-based guidelines for the prevention of CLASBSIs is needed in China.
Our results also indicated that sex, length of time of ICU nursing, educational level, nursing level, establishment of nurses, hospital grade, and incidence of CLABSI were significantly associated with total knowledge score of the ICU Nurses' Knowledge of Evidence-Based CLABSI Prevention Questionnaire. These results are similar to those of other studies [11,15,22], and suggest that more years practicing nursing, which leads to greater experience, and formalized education can improve knowledge and practice of evidence-based guidelines for preventing CLABSIs.
In the study, 59.02% (435/835) nurses worked in an ICU for < 1 year. Thus, the proportion of nurses with a relatively low ICU experience level was large. One reason for this is that the students who helped distribute the questionnaire had graduated in 2019 and thus nurses most accessible to them were those who had recently graduated as well and thus did not have many years of experience. This is a selection bias caused by RDS. Nurses who had worked in an ICU for 3 or more years had a correct answer rate of 45.45% (5/11) of the questionnaire, which is similar to the results of other studies [9,11].
In China, for nurses performing the same duties, establishment nurses are the highest paid, followed by personnel agent nurses. However, "equal pay for equal work" is being advocated in China, and the pay gap between different classes of nurses is getting smaller [24]. Our results showed that contract nurses scored higher on the prevention knowledge of CLABSI than the other two categories of nurses. Further research is needed to determine the causes of this result.
Our results also showed that in addition to a lack of knowledge of evidence-based guidelines to prevent CLABSIs by the CDC, US and the Department of Health UK, the actual practice of the techniques and methods to prevent infections was poor as compared to the results of other studies examining practices in ICUs [9,22]. This includes the use of 2% chlorhexidine gluconate, replacement groups, maximum aseptic barrier precautions, application of transparent dressings, and removal of catheters, the application of suture-free fixation instruments. On-the-job training is needed to promote the application of evidence-based nursing measures for central venous catheters in China.
There are still some limitations to this study. The study provides a comprehensive examination of ICU nursing knowledge and practices in Guangdong Province. However, the results may not reflect the knowledge and practices of ICU nurses in other parts of China. In addition, the overall questionnaire response rate was 835/2607 (32.03%), which can also lead to bias. Half of the respondents worked in an ICU for < 1 year, which contributed to the overall low scores. Our results did show that nurses with more experience had higher scores. A marked strength of this study is the large number of participants and the large number of hospitals represented; thus, the findings can be considered an accurate representation of the geographic region.

Conclusion
The results of this study indicate that Chinese ICU nurses in Guangdong Province have a great lack of knowledge and practice of evidence-based guidelines for the prevention of CLABSIs. These results suggest that national health administrations should adopt policies to provide training for ICU nurses regarding the evidence-based guidelines and practices to prevent CLABSIs.