What are the indications for central venous catheters, how can catheter‑related bloodstream infections be prevented, what complications should be monitored, what is the appropriate dressing‑change protocol, and how should blood cultures be obtained from a central line?

Central Venous Access Lines: Comprehensive Management Guide

Indications for Central Venous Catheters

Central venous catheters are indicated for long-term intravenous therapy (>5-14 days), administration of vesicant/irritant medications or high-osmolarity solutions, parenteral nutrition, chemotherapy, hemodynamic monitoring, and when peripheral venous access is unachievable. 1

Device Selection by Duration

• Short-term use (<30 days): Non-tunneled central catheters when peripheral access fails 1
• Long-term use (>30 days): Tunneled catheters for chemotherapy, antibiotics, parenteral nutrition, or blood products 1
• Long-term intermittent therapy (≥6 months): Implantable ports carry the lowest infection risk among long-term devices 1
• Peripheral-compatible infusates in critically ill patients: Use peripheral IV (≤5 days) or midline catheters (6-14 days) instead of PICCs unless duration is ≥15 days 1

Site Selection Algorithm

• Preferred site: Subclavian vein access demonstrates lower catheter-related bloodstream infection rates compared to femoral and possibly jugular sites 1, 2
• Avoid femoral access whenever possible due to 10 times higher thrombosis risk than subclavian access and increased infection risk 1, 2
• Avoid subclavian site in hemodialysis patients and those with advanced kidney disease due to risk of subclavian vein stenosis 2
• Internal jugular access may have lower mechanical complication risk than subclavian, though ultrasound guidance has reduced site-specific differences 2

CLABSI Prevention Strategies

Use 2% chlorhexidine with alcohol for skin antisepsis and apply maximal sterile barrier precautions during insertion to reduce catheter-related bloodstream infections. 3, 1

Evidence-Based Prevention Measures

• Maximal barrier precautions: Cap, mask, sterile gown, sterile gloves, and sterile full-body drape during insertion 3, 1, 2
• Ultrasound guidance: Mandatory for all CVC insertions to increase success rates and reduce complications including pneumothorax, arterial puncture, and air embolism 1, 2
• Skin antisepsis: 2% chlorhexidine with alcohol; if contraindicated, use tincture of iodine, iodophor, or 70% alcohol 3, 1, 2
• Single-lumen catheters: Use minimum number of lumens necessary to reduce infection risk 3, 2
• Tunneled/implanted catheters: Reduce infection risk in long-term use 3
• Antimicrobial-coated catheters: Reduce infection risk in short-term use only 3
• Hub disinfection: Disinfect hubs, stopcocks, and needle-free connectors before each access 3
• Administration set changes: Replace IV tubing every 72 hours unless clinically indicated 3

Interventions NOT Effective for CLABSI Prevention

• Do not use: Routine antibiotic prophylaxis, routine catheter replacement on scheduled basis, in-line filters, or heparin for infection prevention 3
• Antibiotic lock: Effective only in neutropenic patients with long-term venous access; not recommended routinely 3

Complications and Monitoring

Infectious Complications

The risk of catheter-related bloodstream infection is approximately 5 per 1000 catheter-days. 4

• Daily assessment: Evaluate insertion site daily by palpation through dressing or visual inspection with transparent dressings for redness, drainage, and fever 2
• Catheter-related bloodstream infection rate: Approximately 5 per 1000 catheter-days 4
• Femoral catheter infection rate: Approximately 2.7 per 1000 catheter-days (higher than other sites) 2

Thrombotic Complications

The risk of thrombosis is approximately 3 per 1000 catheter-days, with femoral access carrying 10 times higher risk than subclavian access. 4, 1

• Symptomatic thrombosis: Occurs in 4-8% of cases; asymptomatic thrombosis detected by venography ranges from 27-66% in cancer patients 2
• Major complications: Pulmonary embolism and sepsis 2
• Minor complications: Tip clots, lumen obstruction, and fibrin sheath formation 2
• Prevention strategies: Position catheter tip parallel to vessel wall in lower SVC or upper right atrium; use smallest caliber catheter compatible with therapy; ultrasound guidance at insertion 3, 2
• Prophylactic anticoagulation: Low molecular weight heparin effective only in patients at high risk for thrombosis 3

Mechanical Complications

• Pneumothorax and arterial puncture: Reduced significantly with ultrasound guidance 1, 2
• Catheter tip malposition: Increases risk of thrombosis, erosion, and pericardial tamponade; confirm position with post-insertion chest X-ray 2
• Pinch-off syndrome: Subclavian insertion carries risk of catheter compression between first rib and clavicle; reduced with ultrasound guidance 2
• Air embolism: Prevented by proper insertion technique and patient positioning 1

Proper Blood Culture Collection

When catheter-related bloodstream infection is suspected, obtain paired blood cultures—one from a peripheral vein and one from the catheter—with differential time to positivity monitoring. 3

Diagnostic Protocol

• Paired quantitative blood cultures: One percutaneously and one from the catheter, with continuously monitored differential time to positivity 3
• Alternative method: Quantitative or semi-quantitative culture of the catheter when removed or exchanged over guide wire 3
• Do not culture routinely: Culture catheters only when catheter-related bloodstream infection is suspected, not as routine practice 3
• Preferred culture method: Quantitative or semi-quantitative cultures are preferable to qualitative cultures 3

Dressing Change Protocol and Assessment

Replace dressings when the catheter is removed or replaced, or when the dressing becomes damp, loosened, or soiled. 3

Dressing Management

• Frequency: Change dressing when catheter is removed/replaced, or when dressing becomes damp, loosened, or soiled 3
• Diaphoretic patients: Replace dressings more frequently 3
• Bulky dressings: If dressing prevents palpation or direct visualization, remove and visually inspect catheter site at least daily, then apply new dressing 3
• Daily inspection: Evaluate insertion site daily by palpation through intact dressing or visual inspection with transparent dressings 2

Catheter Removal Criteria for Short-Term Lines

Remove short-term central lines immediately if there are evident signs of local infection at the exit site, clinical signs of sepsis, positive culture of exchanged catheter, or positive paired blood cultures. 3

• Mandatory removal: Erythema or pus at exit site, clinical signs of septic shock, positive culture of catheter exchanged over guide wire, or positive paired blood cultures 3
• Continue antibiotics: Appropriate antibiotic therapy should be continued after catheter removal 3
• Do not exchange over guide wire: If evidence of infection at exit site or CRBSI, remove catheter and insert new one at different site 3
• Staphylococcus aureus bacteremia: Perform trans-esophageal echocardiography to rule out endocarditis due to high rates of complicating endocarditis 3

Long-Term Catheter Management

• Removal required: Tunnel infection or port abscess, septic shock, positive cultures for fungi or highly virulent bacteria, complicated infection (endocarditis, septic thrombosis, metastatic infections) 3
• Salvage attempt: In other cases, attempt to save device using antibiotic lock technique 3

Routine Maintenance

• Flushing protocol: Most central venous access devices can be safely flushed and locked with saline solution when not in use 3
• Heparinized solutions: May be used as lock (after flushing with saline) for implanted ports or open-ended catheter lumens scheduled to remain closed for >8 hours 3
• Femoral catheter duration: Limit to 5 days maximum when possible, particularly in non-bedbound patients 2