IV Catheters

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IV Catheters

By Lisa S. Higa

Today's hospitals rely on IV catheters as essential tools to deliver IV medications, blood products, and nutritional fluids to patients. Approximately, 90% of all patients entering the hospital environment for care have some form of intravenous therapy during their hospital stay. Administering vital medications to these patients through the use of IV catheters can be complicated by related serious infections. Complications of peripheral IV site therapy are typically grouped into localized, mechanical, or systemic categories. When peripheral IV sites fail, patients typically experience localized phlebitis. Replacing peripheral IV catheters can be challenging if the patient has poor peripheral venous access resulting in medication and intravenous fluid schedules disrupted. Complications may progress forming a thrombus, causing thrombophlebitis, or catheter-associated infections or bactermias. Based upon current knowledge, it is impossible to predict which patients will develop peripheral cannula associated complications causing repetitive peripheral IV failure, but recent data evaluating the performance of individual peripheral IV sites suggests a repetitive pattern to site failure. When repetitive peripheral IV access fails and intravenous medication doses and fluids are missed, healthcare providers consider placing the more expensive devices such as peripherally inserted central catheters (PICC) or implantable ports.

The duration of the intravenous site may range from minutes to months and should be the first criteria to consider when selecting an IV catheter. The primary goal of the healthcare provider is to select the appropriate IV device and initiate therapy with the shortest, smallest gauged catheter that is therapeutically and economically necessary to sustain the treatment effect safely. Reported incidences of phlebitis ranged from 10% to 90% of peripheral IVs with symptoms occurring within eight hours of placement. In response to early studies, intravenous drug manufacturers and pharmacists recommended adjusting medication dilution volumes and increasing infusion times for piggyback medications. As a result, a few recent studies cite decreases in the incidences of phlebitis as little as 2% to 22%. The least frequent episodes of phlebitis occur at PICC and CVC cannula sites.

Patients with short term peripheral IV or intravenous catheters may develop phlebitis as a complication, but rarely are these types of catheters associated with major blood-stream infections. When patients move their extremities, the mechanical movement jostles peripheral intravenous catheters as well. The insertion site may eventually show irritation leading to phlebitis with short term peripheral intravenous catheter usage-skin preparation, length of use, activity of catheter site, skin contamination, catheter material, and chemicals/medications administered. When the vein/artery is irritated, the risk of catheter-related infection increases as well. Peripheral arterial catheters often monitor hemodynamic status of acutely ill patients or are used to administer chemotherapy. Incidence of catheter-related infections, especially serious bloodstream infections is reported to be even lower than those associated with short term peripheral venous catheters. Though no study has identified why peripheral arterial catheters have lower rates of infection, two possible explanations are that vascular pressures are higher and that, located on the extremities, these sites are less affected by a patient's small motor movements. As with most catheter sites, inflammation at the insertion site or duration of over four days will make the patient more susceptible to catheter-related infections. Central venous catheters are associated with 90% of all catheter-related bloodstream infections. These multi-luminal types of catheters are the most commonly used by physicians for administering fluids and monitoring pressure of critically ill patients. Yet, because of the multiple ports, manipulation at the catheter site lead to trauma. Eventually, this and other factors, such as seriousness of the patient's condition, the site, lengthy duration of catherterization, and other factors contribute to a high risk of infection. The higher the number of lumens, the greater the risk of contamination.

Central arterial catheters take introducers and remain in place for approximately three days. Most use heparin locks, which reduce thrombosis and cut down on microbial adherence to the catheter. Longer insertion times and catheter insertion without using the highest level of protective barriers (gloves, drapes, masks, and gowns), location of the catheter, and condition of the patient all contribute to higher levels of infection in this type of catheter. Peripherally inserted central venous catheters (PICCs) insert into the superior vena cava by using cephalic or basilic veins. Because of their peripheral insertion, PICCS are associated with fewer complications due to mechanical manipulation (thrombis, phlebitis) and lower rates of infection than other central venous catheters. Longer insertion durations (10 days to 12 months) are possible, with no established or predetermined cut offs backed by research.

The skin offers a high level of protection from infection; therefore, tunneled central venous catheters and totally implanted intravascular devices reportedly have low rates of catheter-related bloodstream infections from 10 to 20%. These devices require surgical insertion and are generally used for patients requiring long-term vascular access (chemotherapy, home infusion, and hemodialysis. Midline catheters do not enter central veins, but instead are peripherally inserted with the tip terminating in the proximal portion of the extremity. Midline catheters are gaining in popularity because of their lower incidence of infection as compared to central catheters. They are soft, composed of silicone or polyurethane. Duration ranges around two to four weeks for this type of catheter.

Prevention Strategies

Each manufacturer has a different approach to improving catheter use-latex-free, needle-free, embedded antiseptic, safety valved, sheated, and prepackaged prep. Expert techniques of approaching a patient's IV needs have changed over time as well. "Using today's nursing techniques," says Lynne Moeser, consultant, IV Technologies, "we assess the patient's venous status, consider the patient's past histories, project the length of therapy and medications to be infused first. Then we identify venous access devices available, consider the costs associated with each, inform, and discuss options with the patient--then make the appropriate device selection.

"My hope is that IV clinicians and infection control clinicians can work together more closely in the future. Early assessment of a patient's IV needs is imperative. There would be distinct patient benefits and healthcare dollars saved if more attention were given to correlation of the proper IV device with the therapy ordered, the patient history and diagnosis, and vascular condition at the time of hospital admission," she concludes.

Innovative practices require new devices, and practices improve constantly. Because new devices enter IV therapy constantly, hospitals must train healthcare workers on the indications for the methods of inserting IV catheters. Education and training are vital in the fight to reduce infections and complications associated with vascular access devices.



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