Background

Central venous catheters (CVCs) are responsible for an estimated 250,000-400,000 bloodstream infections per year, with an associated mortality of 10%-35%. Colonization of the external surface of the catheter, distal spread of organisms down the catheters' intraluminal surfaces, and tap water have all been implicated in CVC infections.

Methods

In February, 2005, twenty-nine patients were prescribed and used the CD-1000, a new surgical dressing, to protect their catheter and exit site wound while performing high risk activities such as showering. This retrospective review was performed to evaluate the effectiveness of the CD-1000 at protecting the catheter and exit site from water and debris. In addition, patient satisfaction with the dressing and catheter infection rates were evaluated.

Results

The patient group used the CD-1000 for an average of 76.13 days (range, 26-147 days), and 96.4% reported that it was effective at keeping the catheter and exit site dry and clean while showering, and would recommend use of this dressing to anyone living with a catheter. Eleven of the 29 patients (37.9%) reported having had a catheter infection prior to using the CD-1000. During the study period there was 1 catheter infection (3.5%) resulting in a catheter infection rate for the study interval of 0.45/1,000 catheter days.

Conclusion

The CD-1000 allowed patients living with CVCs to return to showering and to engage in other high-risk activities previously not allowed. The dressing performed its intended function of maintaining a dry and clean environment for the catheter and exit site with a high level of satisfaction from the patients along with a low rate of infection during the study interval.

In the United States, there are more than 5 million central venous catheters (CVCs) inserted annually.[1],[2] Although the majority of these catheters are inserted for acute care needs and removed within hours to days, others remain in place for months to years. Regardless of their use, CVCs are responsible for an estimated 250,000-400,000 bloodstream infections per year, with an associated mortality of 10%-35%.[2]

Studies have identified 2 major sources of catheter-related infections. The first and most recognized is colonization of the external surfaces of the catheter by organisms from the patient's skin surrounding the catheter.[2] The second is contamination of the catheter hub, with distal spread of organisms down its intraluminal surface.[2] In addition, a study by the Centers for Disease Control and Prevention (CDC) identified tap water as a significant source of infection for patients with central venous access.[3]

On the basis of these and other findings, most clinicians advise their patients to keep their catheters dry and clean to reduce the risk of infection. Patients are often instructed to refrain from showering in order to keep their catheters dry. From a clinician's standpoint, this is a prudent recommendation, but from a patient's perspective, it is not realistic. Some physicians allow their patients to shower, advising them to protect catheters and exit site wounds from water as best they can. This often results in patients attempting to cover catheters and exit site wounds with homemade remedies such as plastic wrap or plastic bags and tape. At best, these homemade dressings are inconsistent at performing their intended function of keeping the catheter and exit site wound dry.

Recently available is a new surgical dressing, the CD-1000 (SDA Product, Miami, Fla.), that addresses the issue of home catheter protection while patients engage in high-risk activities. We began prescribing this product to our dialysis patients with tunneled CVCs. The CD-1000 is a composite wound dressing designed specifically for patients living with in-dwelling catheters. This dressing protects the catheter, hub, and exit site wound from fluid and debris. In this retrospective review, patients reported a high level of satisfaction with the CD-1000. There was also a low CVC infection rate during the study interval.

 Materials and Methods

In February 2005 we began prescribing the CD-1000 composite wound dressings to patients living with tunneled hemodialysis catheters. Patients were instructed to use the dressing at home when they were engaging in high-risk activities, such as showering or working around the yard. Patients were prescribed 3 dressings per week for as long as the catheter was in place, a practice in keeping with Medicare guidelines for use of the dressing.

The CD-1000 consists of an outer removable tarp that covers an inner composite dressing and pouch. The composite dressing and pouch houses the catheter and covers the exit site wound. Once the high-risk activity is complete, the outer tarp can be removed by pulling on the tarp while securing the composite dressing, allowing the tarp to be released from the dressing at its perforated edge. The composite dressing and protective pouch can be worn for as long as needed, typically for hours to days

Every patient prescribed the dressing was given instructions on its use prior to leaving our office. Patients were instructed to either apply the dressing over their existing catheter dressing or to remove the catheter dressing and apply the dressing directly over the catheter and exit site. Patients were instructed to apply the dressing by initially inserting the CVC hubs through the slit in the blue absorbent pad, allowing the hubs and distal catheter to reside in the dressing's pouch.

Next, patients were instructed to position the dressing, pouch, and covering tarp in a manner that would allow the dressing to cover the desired area with minimal to no gathering of the dressing. Once the dressing was felt to be in the proper position, patients were instructed to remove the covering from the tape surrounding the blue absorbent pad (inner composite dressing). Once the pad was secured in place, patients were instructed to position the tarp over the dressing and pouch, allowing the tarp to cover the chest wrapping around the chest to a patient's back. Once the tarp was felt to be in proper position, patients were instructed to remove the tape covering for the tarp securing the tarp in place.

Patients were requested to initially use the dressing for showering immediately prior to going to dialysis and to remove the outer tarp after showering, leaving the dressing in place. Once they reached dialysis, a nurse could visually inspect the dressing to ensure that it was properly placed and was clean and dry. Patients were also instructed that if the dressing, or any dressing around their catheter, became moist or wet, they should immediately remove it and replace it with dry gauze and tape.

Twenty-seven of the 28 patients who did not have an infection, and reported that the dressing kept the catheter and exit site clean.

From February through July 2005, 29 patients were prescribed and used the CD-1000 for home catheter care. The mean number of days the dressing was in use was 76.13 (range 26-147). At the end of the review period, 22 patients were still using the dressing. Of the patients not using the dressing, 5 stopped using it when their catheters were removed, and 2 stopped using it with their catheters still in place. One of these 2 patients discontinued use of the dressing because of a preference for bathing rather than showering; the other had difficulty applying the dressing. Eleven patients (37.9%) reported a catheter infection prior to use of the CD-1000.

During the study, only 1 patient had a catheter infection (3.5%), for an infection rate of 0.45 infections per 1000 catheter days. Twenty-seven of the 28 patients who did not have an infection (96.43%) reported that the dressing kept the catheter and exit site clean and dry while engaging in high-risk activity. Twenty-seven patients reported ease of use on a scale from 1 (easy) to 5 (hard). In the first week ease of use was rated 2.65, improving to 1.84 after the first week of application of the dressing. Twenty-seven of 29 patients (93%) requested to use the dressing for as long as their catheters remained in place, and 28 (96%) stated that they would recommend the CD-1000 to patients chronically living with catheters.

Living with a CVC is a challenge for both patient and caregiver. These catheters, often a necessary evil, are fraught with difficulties. CVCs used for hemodialysis have a lower patency rate and higher infection rate than do dialysis grafts or fistulae. The relative risk of infection-related hospitalization and infection-related death is increased two- to threefold among catheter-dependent hemodialysis patients compared with those using fistulae or grafts.[4-6] Although many dialysis patients only require CVCs for a short period while awaiting fistulae or graft maturation, for others, CVCs are their only access option.

This retrospective review evaluated the impact of a new composite dressing, the CD-1000, on hemodialysis patients living with CVCs. Prior to this study, in our practice - as in many others - patients with CVCs were instructed not to shower or engage in activities that would place the catheter or exit site wound at risk for contacting water or debris. Although this was our recommendation, we recognized that it was often not carried out. Some patients would wrap their chest in plastic wrap; or cover their catheter with a plastic bag and tape and attempt to shower. Although this worked for some, it was not consistent and therefore not recommended. Others would shower without using any protection over the catheter or exit site, against our recommendations. This led to a rate of catheter infections in our practice that we estimated to be 2.5-5 infections per 1,000 patient days depending on the time of year, a rate similar to those described in the literature.[4]

Given this infection rate, along with the knowledge that patients were showering and engaging in high-risk activities against our recommendations, we believed it would be prudent to identify a means of CVC protection that was reasonable for both patient and clinician. The CD-1000 enabled us to recommend showering to our patients with a sense of confidence that their catheters would be protected. We were able to instruct patients on how to properly protect their catheters when engaging in high-risk activities. From our perspective, this prospective approach to catheter care was a vast improvement over our old approach of recommending unrealistic care.

Although the number of infections per 1,000 patient days could not be determined in the 29 study patients with a matched interval prior to use of the dressing, 37.9% of the patients reported having had at least 1 catheter infection prior to its use. This is of interest as it has been demonstrated that the patients at greatest risk of developing catheter-related bacteremia are those with a prior episode of catheter-related bacteremia.[4],[7] Given that a large percentage of the patients in this study had had an episode of catheter-related bacteremia prior to using the CD-1000, it is remarkable that the infection rate for the study interval was only 0.45 per 1,000 patient days for patients who were instructed to engage in high-risk activities.

Although there is controversy in the literature on catheter care with regard to dressing type (occlusive vs. nonocclusive) and use of ointments, there is no controversy about the frequency and severity of catheter-related bloodstream infections. As previously mentioned, colonization of the external surfaces of catheters by organisms from the patients' skin surrounding the catheters and contamination of the catheter hub with distal spread of organisms down its intraluminal surface are the 2 most frequent causes of CVC infections.[2]

In addition, tap water, as demonstrated in the CDC study by Do et al.,[3] also plays a significant role in CVC infections. They showed, that among patients with central venous catheters, those at greatest risk of developing a bloodstream infection had been allowed to shower rather than bathe and to get their exit site wet.[3] The CD-1000 addresses all 3 of the factors associated with CVC infections. It protects the catheter, the exit site, and the catheter hub from water and debris.

Although it cannot be absolutely determined that the use of the dressing was the sole factor responsible for the low infection rate in this study, it is noteworthy that the infection rate of these patients was so low while engaging in a high-risk activity like showering. The dressing allowed our patients to reclaim a piece of their precatheter life by allowing them to shower and engage in other normal life activities that had not been allowed prior to its use.

References

1	Penne K. Using evidence in central catheter care. Semin Oncol Nurs. 2002; 18(1): 66-70.
2	Fraenkel DJ, Rickard C, Lipman J. Can we achieve consensus on central venous catheter-related infections?. Anaesth Intensive Care. 2000; 28: 475-490.
3	Do AN, Ray BJ, Banerjee SN, et al. Bloodstream infections associated withe needleless device use and the importance of infection-control practices in the home health care setting. J Infect Dis. 1999; 179: 442-448.
4	Allon M. Dialysis catheter-related bacteremia: treatment and prophylaxis. Am J Kidney Dis. 2004; 44: 779-791.
5	Pastan S, Soucie M, McClellan WN. Vascular access and increased risk of death among hemodialysis patients. Kidney Int. 2002; 62: 620-626.
6	Allon M, Depner PA, Radeva M, et al. Impact of dialysis dose and membrane on infection-related hospitalization and death: results of the HEMO Study. J Am Soc Nephrol. 2003; 14: 1863-1870.
7	Marr KA, Sexton DJ, Conlon PJ, Corey GR, Schwab SJ, Kirkland KB. Catheter-related bacteremia and outcome of attempted catheter salvage in patients undergoing hemodialysis. Ann Intern Med. 1997; 127: 275-280.