Chapter 12
Catheter Care
This chapter discusses primarily the nursing tasks that need to be carried out long after the physician has placed a catheter. These issues are crucial to the long, effective life of the catheter and must be understood by all members of the venous access service.
Physicians placing central venous catheters must control wound care and dressing changes as needed, never assuming that catheter care and dressing changes will be handled appropriately by the admitting service (if other than the catheter service). If a catheter is not appropriately cared for, the risk of catheter-related infection increases. Even if orders for catheter care are written by the admitting service, these orders vary from one service to the next and can stray from the “state-of-the-art” techniques available for preserving the catheter. A perfectly placed and positioned catheter is useful only as long as it remains in place. If an infection occurs and the catheter must be removed, it does not matter how well it was placed initially. Therefore, the catheter service should write detailed postprocedure orders for catheter care and dressing changes.
DRESSING MATERIAL
Numerous studies have been conducted to identify and examine factors related to the incidence of infection in patients with central venous catheters. Most catheter-related infections (CRIs) appear to result from the migration of skin organisms at the insertion site into the subcutaneous tract, with eventual colonization of the catheter tip.1 Another important contributor to colonization of the catheters is colonization of the catheter hub.1–3 Less common mechanisms of CRI include hematogenous seeding of the catheter tip from a distal focus of infection and administration of contaminated infusate. According to guidelines of the Centers for Disease Control (CDC), an estimated 200,000 cases of nosocomial CRIs occur each year. CRI results in increased morbidity, mortality rates of 10 to 20%,4 prolonged hospitalization (mean, 7 days),5 and increased medical costs in excess of $3500 to $6000 per hospitalization6,7 (1988 U.S. dollars).
Most CRIs begin as local infections of the catheter wound caused by organisms that colonize the patient’s skin. Several prospective studies reported coagulase-negative staphylococci, a predominant organism on human skin, as a common source of CRI.1,2,9–13 These studies reported a correlation of heavy colonization of the insertion site with CRI. Furthermore, Maki and Ringer,1 through a multivariate analysis, suggest that moisture under the dressing contributes to colonization and increased risk of CRI.1 The CDC guidelines for the prevention of intravascular infections14 state that because most intravenous (IV)-related infections result from inward progression of microorganisms contaminating the wound, control measures should prevent contamination of the site. Recommended measures include the use of sterile dressings, preparation of the site, and hand washing.
Transparent Adhesive Dressings versus Gauze Dressings: The Debate Continues
One of the most actively researched and controversial areas of catheter site care is the use of transparent adhesive dressings (TAD). Polyurethane transparent films became available for use as wound and catheter dressings in the late 1970s and offer many advantages, such as allowing continuous inspection of the site, securing the device, and allowing patients to bathe and shower. Concerns have been raised, however, regarding the potential increase in moisture under TAD8 resulting in greater colonization and the possible increased risk of CRI.10,15–20 Numerous studies have addressed these issues and are summarized in Table 12–1. A review of these studies indicates that the question of whether TAD increases risk of CRI, compared with sterile gauze dressings, has not yet been answered.
Summary of the Literature: Dressings and Catheter-Related Infection
The difference in the CRI rate between TAD and gauze dressings remains controversial because contradictory results have been obtained. Some studies have suggested a trend of higher infection rates with TAD; however, statistical significance has not always been achieved because of small sample sizes in the individual studies. Other studies have concluded that there is no difference in infection rates for patients using the various dressing types, and some have suggested a higher infection rate with the use of sterile gauze and tape. Comparison of these studies is difficult because of differences in methods of wound care, methods of culturing, and definitions of infection. The question of which dressing prevents CRI more effectively has not been answered.
Further complicating the picture is the use of different types of TAD in the various studies. Assuming that collection of moisture under a dressing facilitates colonization of microflora, which, in turn, increases the risk of CRI, it is reasonable to assume that the differences in moisture transmission of dressings would influence the risk of CRI. The permeability of the TAD in these studies varies dramatically. Tegaderm is relatively impermeable to water vapor (moisture vapor transmission rate = 80), Op Site is semipermeable, and Op Site 3000 is highly permeable (moisture vapor transmission rate = 2930).25,26 Using the highly permeable TAD, recent studies suggest lower CRI rates with TAD that are more comparable to CRI rates of sterile gauze dressings.
Table 12–1 Studies of Transparent Adhesive Dressings (TAD) vs. Sterile Gauze and Tape (SGT)
Authors | Nehme and Trigger21 |
Year | 1984 |
Study design | Prospective, randomized |
Patient population | 187 patients on TPN |
Compared | Op Site dressings (T. J. Smith and Nephew LTD, UK) changed every 7 d vs. SGT changed every 2 d |
Comments | Skin prep was the same for both groups |
Results | No statistical significance in CRI between the groups (0.63% in SGT group and 0.34% in Op Site group) |
Authors | Ricard et al.22 |
Year | 1985 |
Study design | Prospective, randomized |
Patient Population | 200 postop patients in the ICU |
Compared | SGT Vs. Op Site film changed every 2 d Vs. Op Site film and Op Site spray changed every 2 d Vs. Op Site film and Betadine spray changed every 2 d Vs. Betadine ointment |
Results | No statistical significance for colonization under the dressings between groups. No statistical significance for catheter-related sepsis between groups |
Authors | Make and Ringer et al.1 |
Year | 1987 |
Study design | Prospective, randomized |
Patient population | 1088 patients with peripheral catheters |
Compared | Sterile gauze and tape changed every 2 d Vs. Tegaderm Vs. transparent dressing with iodophor antiseptic incorporated into the adhesive |
Comment | Large sample size allows for generalization of findings for identifying risk factors of CRI |
Results | No statistical significance for rate of catheter infection between the groups; CRI 4.6–6.1% |
Authors | Petrosino et al.15 |
Year | 1988 |
Study design | Prospective, randomized |
Patient population | 92 cancer patients with long-term catheters |
Compared | SGT Vs. no dressing Vs. Op Site Vs. Tegaderm |
Results | No statistical significance of CRI between the groups although the “trend” was toward a higher infection rate with the two transparent dressing groups. The “no dressing” group had the lowest infection rate |
Authors | Conly et al.16 |
Year | 1989 |
Study design | Prospective, randomized |
Patient population | 79 patients |
Compared | Sterile gauze with tape changed every 2 d vs. Op Site changed every 2 d (Smith and Nephew, Lachine, Quebec) |
Results | Statistically significantly more colonization of catheter sites after 48 hours with TAD and statistically significantly more CRI in the TAD group |
Authors | Eisenberg et al.23 |
Year | 1990 |
Study design | Prospective, randomized |
Patient population | 193 patients, 252 catheters |
Compared | SGT changed every day vs. Op Site changed every 7 d |
Comments | Found decreased nursing time and decreased costs with TAD |
Results | No statistical significance in CRI between groups |
Authors | Shivnan et al.24 |
Year | 1991 |
Study design | Prospective, randomized |
Patient population | 98 bone marrow transplant patients with long-term venous catheters |
Compared | SGT changed every day vs. Tegaderm (3M Co., St. Paul, MN, U.S.A.] changed every 4 d |
Comments | 1. Found increased skin irritation with tape and gauze 2. Statistically significant increased patient satisfaction with TAD 3. Difference in nursing time was highly significant between the groups: TAD group required 172.7 min nursing time/30 d and the SGT group required 377 min nursing time/30 d 4. Higher costs of supplies for the SGT group: $87.08/30 d compared with the TAD group, which cost an average of $27.06/30 d |
Results | No statistical significance in CRI between groups. There was 1% CRI in both groups. |
Authors | Maki et al.25 |
Year | 1994 |
Study design | Randomized, prospective |
Patient population | 442 patients with pulmonary catheter |
Compared | SGT replaced every 2 d vs. Tegaderm replaced every 5 d vs. Op Site 3000 replaced every 5 d |
Results | No statistical significance in catheter colonization or sepsis between the groups. There was, however, greater colonization of the skin under the dressings of the TAD group |
Authors | Brandt et al.26 |
Year | 1996 |
Study design | Randomized, prospective |
Patient population | 101 cancer patients with long-term tunneled catheters |
Compared | SGT changed every day vs. Op Site 3000 changed every 7 d |
Comments | Cost of supplies greater for the SGT group averaging $23.10/week compared to the cost of the Op Site 3000 group, which averaged $8.98/wk |
Results | No statistical significance when all categories of CRI considered between the groups |
Authors | Treston-Aurand et al.5 |
Year | 1997 |
Study design | Retrospecive, nonrandomized |
Patient population | 3931 patients with various central venous catheters |
Compared | SGT changed every day vs. Tegaderm changed every 2 d vs. Op Site 3000 |
Comments | Greater staff satisfaction with TAD |
Results | Statistically significant more CRI with SGT |
Patient Satisfaction
Studies that have compared patient satisfaction among dressings have shown greater patient satisfaction with TAD because fewer dressing changes are required, and because patients do not need to be as vigilant about not getting the dressings wet (they can take showers).
Personnel Satisfaction
Studies that evaluated staff acceptance have shown significantly greater satisfaction with TAD.
Costs
Although the cost of a single TAD is greater than a single dressing of sterile gauze and tape, TAD need be changed only every 4 to 7 days instead of the daily changes required for gauze dressings. Studies have shown overall cost savings for supplies with TAD.5,24 In addition, cost savings are realized with TAD because of decreased nursing time.24,26
Recommendations
Greater patient satisfaction, greater staff satisfaction, and less overall cost while maintaining at least the same quality of care in terms of CRI make TAD a viable (if not preferred) alternative to sterile gauze dressings. Regardless of which alternative one chooses as the primary method of dressing catheters, it is vitally important to realize that viable options exist. Patients’ preference or events such as skin irritation may dictate changing or alternating dressing types.
Perhaps of greater importance than the type of dressing used is the establishment of appropriate catheter care by the nursing staff. One study demonstrated the benefits of a nursing educational program on the CDC recommendations for control of CRI. Statistically significant reduction of inappropriate catheter care and a reduction in the rate of skin colonization have been shown. Because maintenance of catheters by inexperienced staff may increase the risk of catheter colonization,27 many institutions have established infusion therapy teams. Available data suggest that personnel trained in the maintenance of IV access devices can provide a service that effectively reduces catheter-related infections and costs.
DRESSING CHANGE
Techniques
The materials needed are as follows:
• Nonsterile gloves
• Sterile gloves
• Povidone–iodine swab sticks
• Alcohol pads and swab sticks
• Sterile barrier
• Sterile gauze or transparent dressing
• Tape
