How is dialysis performed in a patient without established vascular access?

Dialysis Without Established Vascular Access

When a patient lacks established vascular access, dialysis is performed using a central venous catheter (CVC), with the specific type and insertion site determined by the expected duration of use and clinical urgency.

Immediate Access Strategy

For Urgent/Short-Term Use (<1 week)

• Non-tunneled (uncuffed) catheters should be placed for hospitalized patients requiring immediate dialysis when AVF/AVG is not yet available 1
• These temporary catheters are appropriate for bridge therapy while awaiting AVF/AVG maturation or as emergency access 2, 1
• Femoral vein catheters may be used in bed-bound patients but should not remain in place longer than 5 days 1
• Any short-term catheter must have a documented plan to either discontinue or convert to a long-term catheter within 1 week 1

For Intermediate/Long-Term Use (>3 weeks)

• Tunneled cuffed catheters (TCCs) are recommended when access is needed for more than 3 weeks 1
• These serve as effective bridge therapy during the 3-4 months required for AVF maturation 2
• TCCs are acceptable for short-term duration when AVF or AVG is created but not yet ready for use 2

Preferred Insertion Sites (In Order of Preference)

For Acute Kidney Injury Patients

The site selection follows this hierarchy 1:

1. Right internal jugular vein (first choice) - most direct path to cavo-atrial junction with lowest complication risk 3
2. Femoral vein (second choice)
3. Left internal jugular vein (third choice)
4. Subclavian vein (last choice) - should be avoided when possible due to risk of central venous stenosis that may preclude future AVF/AVG creation 1, 2

For Long-Term Tunneled Catheters (>3 months)

When prolonged catheter use is anticipated without planned AV access, the KDOQI guidelines recommend this order 2:

• Internal jugular vein
• External jugular vein
• Femoral vein
• Subclavian vein
• Lumbar veins

Right-sided placement is preferred over left-sided due to more direct venous anatomy 2, 3

Critical Technical Requirements

Catheter Specifications

• Catheters must achieve rapid blood flow rates of 350 mL/min at prepump pressures not more negative than 250 mm Hg 1
• Silicone or polyurethane materials are preferred 1
• Antimicrobial-coated catheters (minocycline and rifampin) reduce catheter-related bloodstream infection risk 1

Placement Technique

• Ultrasound guidance must be used for all dialysis catheter insertions to reduce complications 1, 3
• Short-term catheter tips should be positioned in the superior vena cava, confirmed by chest radiograph or fluoroscopy 1
• Long-term catheter tips should be positioned in the lower third of the superior vena cava or at the atrio-caval junction (within the right atrium) for optimal flow 1, 3
• Chest radiograph must be obtained promptly after placement and before first use of internal jugular or subclavian catheters 1
• Femoral catheters require sufficient length to reach the inferior vena cava for adequate blood flow 1

Important Clinical Context

When CVCs Are Appropriate

KDOQI guidelines consider tunneled CVCs reasonable for 2:

• Bridge therapy while AVF/AVG matures
• Acute transplant rejection requiring temporary dialysis
• Living donor transplant confirmed with operation date <90 days but dialysis needed
• AVF/AVG complications requiring temporary non-use (major infiltration, cellulitis)

Long-Term CVC Indications (>3 months)

CVCs may be used for prolonged duration in specific scenarios 2:

• Multiple prior failed AV accesses with no available options
• Severe arterial occlusive disease or noncorrectable central venous outflow occlusion
• Limited life expectancy
• Valid patient preference after proper informed consent regarding risks
• Pediatric patients with prohibitively diminutive vessels

Critical Pitfalls to Avoid

Mortality and Morbidity Risks

• Prolonged catheter use increases mortality by 51% and severe infection by 130% compared to AVF/AVG 1
• Less than 10% of chronic maintenance hemodialysis patients should be maintained on catheters as permanent access 2
• Chronic catheter use (>3 months without maturing permanent access) should be avoided 2

Infection Complications

• Systemic and local infections occur more frequently with cuffed catheters than with AV accesses 2
• Routine replacement of catheters at scheduled intervals does not reduce infection rates and is not recommended 1

Vascular Complications

• Subclavian vein access carries significant risk of central venous stenosis (up to 50% of cases), which can preclude future permanent access creation 2, 1
• Chronic catheter access increases risk of central venous stenosis that may prevent establishment of permanent vascular access 2
• Long-term catheters should not be placed on the same side as a maturing AV access 1

Dialysis Adequacy

• Cuffed catheters provide lower blood flow rates compared to AV access, potentially compromising dialysis adequacy 2
• Inadequate dialysis adequacy is associated with increased morbidity and mortality 2

Patient Education Imperative

Patients must be educated on the risks and benefits of catheters and strongly encouraged to allow creation of an AVF for permanent access 2. The initial ease-of-use and painless access offered by catheters may foster patient reluctance to consider more permanent options despite significantly greater infection risk and potential for inadequate dialysis 2.