Introduction to Catheter Related Blood Stream Infections
Catheter related bloodstream infections, also known as CRBSIs, occur when bacteria or other microorganisms travel through an intravenous catheter and enter the bloodstream, causing an infection. Intravenous catheters, also called IV cathetics, IV lines or central lines, are medical devices that are inserted into a vein or artery to deliver fluids, medications, nutrients or blood products directly into the bloodstream. They can remain in place for days, weeks or even months in hospitalized patients. While catheters are lifesaving for many patients, they also increase the risk of developing a bloodstream infection if not placed and cared for properly.
Causes and Risk Factors of CRBSIs
Microorganisms that cause CRBSIS usually enter the bloodstream when the skin surrounding the catheter entry site is contaminated. The most common sources of infection include the patient’s own skin flora and microbes transferred from the hands of healthcare providers during catheter insertion, dressing changes or accessing the catheter port. CRBSIs are more likely to develop the longer a catheter remains in place as this provides more opportunity for bacteria to colonize around the insertion site or travel into the catheter itself. Additional factors that increase risk include the use of non-sterile techniques during placement and maintenance, frequent handling of the catheter, poor skin integrity or tissue damage from tapes/dressings, and underlying conditions such as immunosuppression. Central venous catheters like peripherally inserted central catheters (PICCs) pose higher infection risks compared to peripheral IV lines.
Signs and Symptoms of Catheter Related Bloodstream Infections
Since bacteria from a CRBSI enter the bloodstream directly through an intravenous catheter, they can rapidly spread throughout the body and cause symptoms that may be difficult to attribute directly to the catheter. Common indicators that a patient may have developed a CRBSI include sudden onset of fever, chills, fatigue and general feelings of illness that cannot be explained by another cause. Redness, swelling or pain may also be present at the catheter insertion site. Some patients experience drop in blood pressure or experience confusion, especially if the infection spreads to other vital organs like the heart (endocarditis) or brain (meningitis). Newborn infants and elderly patients may not show typical signs and symptoms.
Diagnosing Catheter Related Bloodstream Infections
To diagnose a suspected CRBSI, healthcare providers typically obtain blood cultures from both the catheter and a separate peripheral vein. A CRBSI is confirmed if the same type of bacterium or fungus grows out in the blood drawn from the catheter at least two hours before growth appears in blood drawn from a separate venipuncture site. Cultures of catheter tips may also isolate pathogens that have colonized on the device. Observing inflammation or pus at the insertion site on physical exam further points to catheter colonization. Imaging tests like chest x-rays may reveal complications like abscesses or lung infiltrates if the infection has disseminated. Blood test abnormalities like elevated white blood cell counts are also common but nonspecific findings. Definitive diagnosis requires identifying the same microorganism in both sets of blood cultures.
Treatment and Management of CRBSIs
Once a CRBSI is confirmed, prompt treatment with targeted intravenous antibiotics is imperative to prevent life-threatening complications. Antibiotic therapy is chosen based on the identity and susceptibility profile of the causative pathogen isolated from blood cultures. The infected catheter also needs to be promptly removed to prevent ongoing seeding of bacteria into the bloodstream from the colonized device. For some patients with limited venous access, “salvage” of the catheter may be attempted using prolonged antibiotic infusion via the infected line while awaiting placement of a new line. However, catheter removal generally leads to better outcomes and is the standard of care for most CRBSI cases. Ongoing monitoring of antibiotic therapy response and surveillance blood cultures are essential to ensure resolution of bacteremia. Treatment duration depends on the pathogen and clinical course but typically lasts at least two weeks for most bacteria.
Preventing CRBSIs Through Best Practices
Infection prevention programs focused on implementing evidence-based standards have significantly reduced CRBSI rates at healthcare facilities. Key prevention practices include optimal catheter insertion technique using full barrier precautions like sterile gloves, gown, mask and hat. Hand hygiene before and after any catheter access and clean dressing changes are equally important. Biopatches that absorb local infection risks can extend catheter dwell time safely. Avoiding unnecessary lines or prolonged use also decreases infection pressure. CRBSI tracking through surveillance methods enables targeted performance improvement in high-risk units. Educating both providers and patients on proper catheter care is a highly effective prevention strategy. Strict adherence to best practices during all aspects of catheter care can substantially decrease CRBSI occurrence and improve patient outcomes. Ongoing research also evaluates novel technologies like antimicrobial impregnated catheters to further suppress infection risks. A coordinated, multidisciplinary effort is required to realize the goal of zero preventable CRBSIs.
In summary, CRBSIs are serious healthcare associated infections associated with significant morbidity, mortality and costs. Despite advances, they remain an ongoing challenge, especially for high-risk populations relying on long-term intravenous access. Clinicians must maintain a high index of suspicion to enable early diagnosis and treatment guided by microbiology results. Prompt catheter removal combined with targeted antibiotics forms the mainstay management approach. Infection control programs aiming to consistently implement evidence-based standards during all aspects of catheter insertion and maintenance offer the best strategy for CRBSI prevention. Continued research, education and performance tracking efforts are still warranted to eliminate these preventable infections, protect patient safety and optimize patient outcomes.