Prevention of Central Line Infections

Prevention of Central Line Infections

Comparison of the skin cleansers Chloraprep and Providone Iodine in Rate of Infections Resulting From Central Lines

CRBSI - Catheter related blood stream infection.

The three most common pathogens causing CRBSI's are coagulase negative staphylococcus, Enterococcus, and Staphylococcus aureus, all of which are commonly resistant to multiple antibiotics and therefore are can be more difficult to treat.

PICC - Peripherally inserted central catheter

CDC - Centers for Disease Control

US Department of Health and Human Services with a goal of promoting "health and quality of life" (CDC Mission).

CDC IA recommendation - a "strongly recommended for implementation and strongly supported by well-designed and experimental, clinical, or epidemiologic studies." (CDC, 2002, pp. 1-34)

FDA - Food and Drug Administration

US Department of Health and Human Services with a goal of "protecting the public health" (www.fda.gov/opacom/morechoices/mission.html)

Fairbanks Memorial Hospital - a 200 bed level 2 trauma facility serving the interior and northern regions of Alaska (FMH).

Introduction

Intravenous catheters are commonly used in caring for patients as a means of providing vascular access. There is however a risk of serious infection associated with IV catheters, which may be local or systemic. These infections may potentially lead to further complications such as catheter related blood stream infection (CRBSI), sepsis, thrombophlebitis, endocarditis and osteomyelitis (CDC, 2002, pp. 1-34). These complications are associated with increased morbidity and mortality, increased length of hospitalization and higher medical costs. However due to the importance of maintaining venous access, these IV catheters are nevertheless considered an essential part of a patient's treatment.

The Center for Disease Control has estimated that a total of 250,000 cases of CRBSI (including PICC's) occur on an annual basis. The mortality rate of these cases is estimated at 12%-25% and the estimated cost to the health-care system is $25,000 per episode (Miller, MD & O'Grady, MD, 2003, pp. s355-s358). These figures indicate the importance of with which health care authorities should treat the risk of CRBSI. The reduction in annual CRBSI rates is essential not only to reducing morbidity and mortality, but also to reducing increasing hospital costs associated with these infections.

The causative organism in nosocomial acquired CRBSIs are the micro-organisms found on the patient's own skin (Hibbard, May/June 2005, pp. 194-207). Although this means that the exposure of patients to these bacteria may first seem inevitable, it actually means that removal of the bacteria should be straightforward given an appropriate antimicrobial solution. Providone Iodine has been the most commonly used antiseptic to prepare the skin for intravenous catheter insertion in the United States in the past, with little viable alternative available. This changed in July 2000 when the FDA approved Chloraprep as a topical antiseptic for skin preparation (Miller, MD & O'Grady, MD, 2003, pp. s355-s358).

Problem Statement

Before the introduction of Chloraprep, Iodine prep was the most commonly performed pre-insertion technique. This involved using 3 swab sticks soaked with Iodine, applied in a circular motion from the insertion site outward. New guidelines from the CDC now recommend using Chloraprep as opposed to this previous method of Iodine prep. The Chloraprep technique is involves using the pre-filled applicator, scrubbing with back and forth action for a full 60 seconds then allowing the antiseptic to remain on the insertion site to air dry before catheter insertion (Medi-Flex, 2005). A study conducted across the U.S. In 2005 showed that 91% of hospitals have now adopted this technique for sterilization prior to catheter insertion (Krein et al., 2007).

Several studies have now been completed to compare the actions of the skin antiseptics Chloraprep and Providone Iodine among others. The results of a Meta-Analysis study "found that the use of Chlorhexidine gluconate rather than Providone Iodine can reduce the risk for catheter-related blood stream infection by approximately 50% in hospitalized patients who require short-term catheterization." The study goes on to state "Given the extent of the benefit and the small incremental cost, chlorhexidine gluconate should be considered as a replacement for Providone Iodine solution, particularly in patients at high risk for catheter related blood stream infection." (Chaiyakunapruk, Veenstra, Lipsky & Saint, MD, 2002, pp. 792-801).

Previous reviews of the meta-analysis studies which have been conducted were performed relatively soon after the initial introduction of chlorhexidine gluconate, and very recently after the change in FDA guidelines recommending the antiseptics use. It has now been some years since the change in practice and this study intends to reassess the available data in an attempt to understand whether the findings remain conclusive in supporting the use of chlorhexidine over Providone Iodine solution in prevention of CRBSIs.

Therefore the clinical problem statement is "What are the most effective antiseptic techniques to use to minimize risk of infection from use of intravenous catheters?"

Description of Methodology

The study attempts to solve the clinical problem statement through a thorough review of the clinical trials which have been conducted globally since the introduction of chlorhexidine. The clinical problem will then be answered through a synthesis of the findings from the studies available. The data will be analyzed based upon the numbers of patients found to have colonization of catheters and the number of patients who acquired CRBSIs as a result of catheterization. The effects of the two antiseptic techniques will be based upon the differences in percentages of patients suffering these two consequences which have been treated with each technique.

The secondary data to be used in the synthesis was collected from a wide range of scholarly sources. This data is considered to be reliable if appearing in a peer reviewed medical journal. This ensures that the data has been assessed by others in the field as being suitable for the purpose and techniques of the study should be reproducible given the format and the platform of the research. The data from scholarly journals is also considered to be valid to this study as it was assembled from peer-reviewed journals publishing results from clinical trials in global health care systems. This is important to ensure that the same results would be observed in the U.S. hospital setting should guidelines be produced based on the results.

In order to search for relevant articles the MEDLINE index was electronically searched across all studies between 1966 and 2007. This was expected to highlight all relevant peer-reviewed journal articles which would be relevant to the study. In addition to this, CINAHL: Nursing and Allied Health was also searched from 1982 to 2007 and International Pharmaceutical Abstracts was searched from 1970 to 2007.

The search strategy was to use the key words 'chlorhexidine' and 'catheter' in a basic search, and if necessary to refine the search using the term 'iodine'. The search was restricted to clinical trials although review articles were searched in order to reveal additional articles which may not have been found through other methods.

The requisites for inclusion in the study were therefore that the study be a randomized trial comparing any type of chlorhexidine gluconate solution with a povidone Iodine solution for vascular catheter site care; the study must also report the incidence of catheter colonization or related bloodstream infection with sufficient data to establish the risk ratio for each antiseptic.

Once all relevant studies within the time frames had been identified, a comparison was drawn between the results of each study. The technique used for this was adapted from Chaiyakunapruk et al. (2002). This was performed by tabulating the relevant data from each study. The percentages of colonization were calculated from each study for those receiving povidone Iodine treatment and those receiving chlorhexidine treatment. The percentages were also calculated for the rates of infection observed in each group. This data was presented in the table alongside data on the average length of time each patient retained the catheter. This allowed for direct comparison between the two groups for each study and also between the various studies. The results from each identified study may be seen in Table 1.

Presentation of Findings

The findings of the study are represented in Table 1. There was found to be only one study which had been conducted since the published review by Chaiyakunapruk et al. (2002). The results of this study were similar to all those found in previous studies which compared the actions of chlorhexidine and povidone Iodine. The results of every study except that by Humar et al. (2000) found that there were reductions in colonization of IV catheters when using chlorhexidine when compared with povidone Iodine. However Humar did agree with the majority of the other studies that there were less CRBSIs found in those who had been treated with chlorhexidine when compared to treatment of povidone Iodine. This result is possibly more important, as the reflection in infection rate is a more reliable measure of the benefits of a treatment. This is due to the cost analysis which will be issued prior to any new technique recommendations in health whereby increases in morbidity and mortality are considered to be key measurable variables. In this case, the measures in colonization reduction will remain relevant as not all studies showed conclusively that there was a reduction in infections associated with chlorhexidine use. One possible explanation for the differences observed in the studies could be that the strengths of the chlorhexidine solution were different. It could also be that over time more effective techniques have been developed in the application of the solution, as the results do appear to improve over time.

There are limitations to the methodology of the study which are centered on the use of secondary data for analysis. The use of secondary data allows a wider range of data to be gathered from across the U.S. than would be practical from primary data collection which is the reason for the choice in this study. However this puts the control of several variables beyond the researcher. The results of the techniques may have been affected by the application of different individuals, departments and hospitals, all of whom may vary techniques and other factors influencing the success of these techniques. The analysis and interpretation of study results by different researchers in each study may also affect the overall outcome, as different researchers will choose to collect and interpret data in different ways, with the only the final versions being available for this study. Despite these limitations, the overall agreement between the different sources suggests that clear conclusions may be drawn from the study for synthesis.

Study

Patient Population

Number of catheters

Mean catheter duration

Proportion of positive cultures with catheter colonization

Catheter related blood stream infection

CHG group

Povidone Iodine group

CHG group

Maki et al., 1991 ICU 214-227 5.3-5.3-5-2.3-21 9.2-1-0.4 Sheeham et al., 1993 ICU 169-177 n/a 3-1.8-12 6.8-1-0.6 Meffre et al., 1995 Across hospital 568-549 1.6-1.6-9-1.6-22 4-3-0.5 Mimoz et al., 1996 ICU 170-145 4.5-3.9-12 7.1-24-16.6-3-1.8 Legras et al., 1997 ICU 208-249 10-10-19 9.1-31-12.4-0-0 LeBlanc and Cobett, 1999 83-161 1.6-1.7-6-7.2-23-16.1 n/a Humar et al., 2000 Any hospital unit 116-116 5.3-6.3-36-31 27-23.3-4-2.1 Langartner et al., 2004 Any hospital unit 45-52-13.3-14.5-11-24.4-16-30.8

Table 1 - Results of the studies which were taken for the analysis of chlorhexidine vs. povidone Iodine in infection control when placing CVCs

In the time period since the introduction of chlorhexidine there have been advances made in alternative solutions. In the study by Langgartner et al. (2004) the effect of combining the two methods of disinfectant was combined in order to assess whether the effects of the disinfectants would combine to produce better results. The study found that only 4.7% of patients were found to have colonization of catheters after receiving both methods of disinfection prior to placement of the catheter. Although this figure is higher than many of the other studies have revealed by either method alone, the figure is much lower than the cases observed in Langgartner et al.'s study for either method alone. Therefore it could be suggested that the combination of skin disinfection with chlorhexidine followed by disinfection with povidone Iodine would be the most effective form of antiseptic treatment before placing an IV catheter. However as there is only one study which shows these results at the present time it would be suggested that further studies would be necessary in order to ascertain whether this is true. The main limitation in the study by Langgartner et al. was that there was no measure of the number of infections which arose as a result of the catheter placement. This means that even though there was a clear reduction in the number of catheters displaying colonization this would not necessarily result in a lower number of infections. It is only if the infections could be lowered through performing both techniques that it would be beneficial as otherwise it would simply increase healthcare costs and prolong the procedure for the patient without visibly better results.