The insertion of a catheter into a body cavity, duct, or vessel to allow drainage, injection of fluids, and/or access by surgical instruments is a common procedure in the practice of medicine. Catheters come in a variety of shapes and forms and can be used for a variety of tasks, including chemotherapy, fluid drainage, hemodialysis, and administering intravenous fluids, anesthesia, or other medications. A peripheral intravascular catheter can be used to administer medication, nutrition, and various other intravenous fluids via peripheral blood vessels, to perform hemodynamic measurements, and to provide access for procedures and devices affecting the cardiovascular system. A central venous catheter can be used to deliver medications or fluids to vessels near the heart or into the heart itself. It is estimated that more than 100 million peripheral venous catheters and more than 250,000 central venous catheters are placed in patients in the United States each year. Other intravascular catheters include those used for hemodialysis, peripheral central access (PIC), interventional procedure access, cardiac ventricular assist device access, and other long term vascular access support. These can be both arterial and venous in respect to the type of vessel in which they are inserted. For these many intravascular catheter uses, the catheter insertion site is traditionally and universally dressed by pressing the round, tubular catheter against the skin of the patient with a sterile adhesive patch-type dressing or with sterile gauze and adhesive tape, which are the two dressing types recommended by the United States Centers for Disease Control and Prevention (“CDC”).
One major problem with intravascular catheterization methods is the risk of infection. For example, infections related to central venous catheters alone occur up to 80,000 times per year in the U.S., leading to 28,000 deaths and costing as much as 2.3 billion dollars per year. The rise of multi-drug resistant organisms has further compounded the magnitude of the problem of intravascular catheter infection, and the lay press and medical literature have paid increasing attention to this problem. As a very significant marker of this concern, the Centers for Medicare and Medicaid recently ruled that costs associated with catheter-related infection will no longer be reimbursed. Because of this, there has been a very strong push by clinicians, hospitals, and insurers to address the problem of catheter related infection. Several improved strategies for catheter care have been introduced, such as using rigorous interval dressing change protocols, applying optimal catheter care techniques, using antibiotic impregnated catheters, using improved dressing materials, and/or supplying antimicrobial additives to the dressing composition.
All of these strategies, however, still have the fundamental drawback of working within the mechanical constraints of the “traditional” patch-type covering dressing. This dressing strategy, which has been used since the first intravascular catheter was placed more than 100 years ago, acts, as stated above, by pressing the tubular catheter against the skin with a flat adhesive dressing that serves to cover both the catheter-skin insertion site and a portion of the catheter external to the body. The fundamental shortcoming of this traditional dressing strategy is that it precludes the creation of a sterile seal at the catheter-skin insertion site, as a gap between the round contour of the catheter and the skin is always left. The size of this gap is larger if the dressing is attached to wider diameter points of the catheter device, such as a catheter hub or an intermediate connector. Inflow of contaminants to the catheter insertion site along these open channels is always a possibility with such methods and devices, and therefore true sterility can never be achieved. In addition, over time, movement of the skin and catheter relative to one another and relative to the dressing can increase the size of the catheter-dressing gap. Furthermore, these dressings cannot be exposed to water or other liquids as these liquids will flow directly to the catheter-skin insertion site, thereby further contaminating this site.
Accordingly, there is a need for catheter dressing methods and devices that provide for improved sealing at the catheter-dressing junction and/or improved sterility at the catheter insertion site. The devices and methods disclosed herein represent a paradigm shift in intravascular catheter care from a non-sterile, non-sealing dressing to a fully sealed and durably-sterile solution.