A catheter is a slender, flexible tube used to introduce or remove fluids, or to access specific body cavities. Maintaining the correct position of catheters is important for their proper function and patient safety. This article explores internal design features and external techniques that keep them securely in place.
Internal Retention Mechanisms
Many catheters incorporate design features that prevent them from dislodging from their intended position.
One common internal retention mechanism involves an inflatable balloon, often seen in Foley catheters used for urinary drainage. Once the catheter tip is positioned within the bladder, a small balloon near the tip is inflated with sterile water through a separate lumen, creating a physical anchor against the bladder wall. This inflation ensures the catheter remains secured, resisting dislodgement.
Another internal securement method utilizes a “pigtail” design, frequently found in drainage catheters such as those used for nephrostomy or biliary drainage. After insertion, the flexible tip of the catheter is advanced into a cavity or duct and then allowed to curl into a tight coil. This curled shape is large enough to resist withdrawal through the smaller insertion site, effectively holding the catheter in place without the need for an external inflation mechanism. Its design allows it to fit within the anatomical space, providing stable retention.
External Securement Methods
Beyond internal anchors, external methods hold catheters securely, preventing movement and reducing complications.
Adhesive dressings are a common approach, using transparent film dressings or medical tapes. These dressings are applied over the insertion site and tubing, adhering to the skin for secure attachment. Transparent films allow visual inspection, while other tapes offer stronger adhesion for longer-term securement.
Specialized catheter securement devices (CSDs) offer a more robust external securement solution. These devices have an adhesive base that attaches to the skin and a mechanism that grips the catheter tubing. Some use clamping or locking mechanisms, while others employ channels the tubing snaps into. They distribute tension more effectively than simple tape, reducing skin irritation and accidental dislodgement.
Sutures provide another direct method of external catheter securement, particularly for catheters requiring strong, long-term fixation, like central venous or percutaneous drainage tubes. A medical professional stitches the catheter directly to the skin near the insertion site using sterile thread. This creates a strong mechanical anchor, minimizing catheter movement at its entry point.
Why Securement Matters
Effective catheter securement is fundamental to patient well-being and effective medical care.
Inadequate securement increases the risk of dislodgement, which can lead to immediate complications. When a catheter dislodges, it can damage surrounding tissues or blood vessels, causing pain, bleeding, or hematoma formation at the insertion site. This also necessitates a new insertion, distressing for the patient and consuming medical resources.
Beyond dislodgement, improper securement can compromise insertion site sterility, increasing infection risk. Catheter movement can create micro-abrasions along the insertion tract, allowing bacteria from the skin to enter the body. This can lead to localized infections, such as cellulitis, or more severe systemic infections like bloodstream infections. Securement also maintains the catheter’s function by ensuring it remains in the correct position for fluid administration, drainage, or diagnostic purposes.