IV Catheters

June 1, 2000

IV Catheters

IV Catheters

By Lisa S. Higa

Today'shospitals rely on IV catheters as essential tools to deliver IV medications, bloodproducts, and nutritional fluids to patients. Approximately, 90% of all patients enteringthe hospital environment for care have some form of intravenous therapy during theirhospital stay. Administering vital medications to these patients through the use of IVcatheters can be complicated by related serious infections. Complications of peripheral IVsite 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 peripheralvenous access resulting in medication and intravenous fluid schedules disrupted.Complications may progress forming a thrombus, causing thrombophlebitis, orcatheter-associated infections or bactermias. Based upon current knowledge, it isimpossible to predict which patients will develop peripheral cannula associatedcomplications causing repetitive peripheral IV failure, but recent data evaluating theperformance of individual peripheral IV sites suggests a repetitive pattern to sitefailure. When repetitive peripheral IV access fails and intravenous medication doses andfluids are missed, healthcare providers consider placing the more expensive devices suchas peripherally inserted central catheters (PICC) or implantable ports.

The duration of the intravenous site may range from minutes to months and should be thefirst criteria to consider when selecting an IV catheter. The primary goal of thehealthcare provider is to select the appropriate IV device and initiate therapy with theshortest, smallest gauged catheter that is therapeutically and economically necessary tosustain the treatment effect safely. Reported incidences of phlebitis ranged from 10% to90% of peripheral IVs with symptoms occurring within eight hours of placement. In responseto early studies, intravenous drug manufacturers and pharmacists recommended adjustingmedication dilution volumes and increasing infusion times for piggyback medications. As aresult, 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 phlebitisas a complication, but rarely are these types of catheters associated with majorblood-stream infections. When patients move their extremities, the mechanical movementjostles peripheral intravenous catheters as well. The insertion site may eventually showirritation leading to phlebitis with short term peripheral intravenous catheter usage-skinpreparation, length of use, activity of catheter site, skin contamination, cathetermaterial, and chemicals/medications administered. When the vein/artery is irritated, therisk of catheter-related infection increases as well. Peripheral arterial catheters oftenmonitor hemodynamic status of acutely ill patients or are used to administer chemotherapy.Incidence of catheter-related infections, especially serious bloodstream infections isreported to be even lower than those associated with short term peripheral venouscatheters. Though no study has identified why peripheral arterial catheters have lowerrates of infection, two possible explanations are that vascular pressures are higher andthat, located on the extremities, these sites are less affected by a patient's small motormovements. As with most catheter sites, inflammation at the insertion site or duration ofover four days will make the patient more susceptible to catheter-related infections.Central venous catheters are associated with 90% of all catheter-related bloodstreaminfections. These multi-luminal types of catheters are the most commonly used byphysicians 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, thesite, lengthy duration of catherterization, and other factors contribute to a high risk ofinfection. The higher the number of lumens, the greater the risk of contamination.

Central arterial catheters take introducers and remain in place for approximately threedays. Most use heparin locks, which reduce thrombosis and cut down on microbial adherenceto the catheter. Longer insertion times and catheter insertion without using the highestlevel 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 ofcatheter. Peripherally inserted central venous catheters (PICCs) insert into the superiorvena cava by using cephalic or basilic veins. Because of their peripheral insertion, PICCSare associated with fewer complications due to mechanical manipulation (thrombis,phlebitis) and lower rates of infection than other central venous catheters. Longerinsertion durations (10 days to 12 months) are possible, with no established orpredetermined cut offs backed by research.

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

Prevention Strategies

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

"My hope is that IV clinicians and infection control clinicians can work togethermore closely in the future. Early assessment of a patient's IV needs is imperative. Therewould be distinct patient benefits and healthcare dollars saved if more attention weregiven to correlation of the proper IV device with the therapy ordered, the patient historyand diagnosis, and vascular condition at the time of hospital admission," sheconcludes.

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



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