Catheterisation — Vascular Access
Vascular access for continuous kidney replacement therapy (CKRT)
Catheter and insertion-site selection
CKRT requires a double-lumen central venous catheter, e.g. a Shaldon catheter, that efficiently provides the necessary blood flow.
KDIGO suggests the following order of sites for a non-tunnelled Shaldon catheter: right internal jugular vein, then femoral vein, then left internal jugular vein, with the subclavian vein as a last option to reduce the risk of central venous stenosis in patients with AKI [1].
Recommended order | Site |
|---|---|
1 | Right internal jugular vein |
2 | Femoral vein |
3 | Left internal jugular vein |
4 | Subclavian vein; last option |
Insertion and care
KDIGO recommends ultrasound guidance when inserting a catheter into the internal jugular or femoral vein. Infection-control precautions and catheter care are implemented according to the institution’s protocol and applicable guidelines [1,3].
Catheter size, length and flow rate are selected according to the insertion site, the CKRT prescription and the device; the function of each lumen is checked before treatment begins.
Jugular versus femoral venous access
In the randomised CATHEDIA trial involving 750 patients, the overall catheter-colonisation rate did not differ significantly between the two sites, and catheter-related bloodstream-infection rates were similar. A subgroup analysis found a difference according to body mass index: catheter colonisation was lower with femoral access in patients with BMI below 24.2, and lower with jugular access in those with BMI above 28.4. These are trial and subgroup findings; site selection is also balanced against patient factors and the team’s experience [2].
Access through an arteriovenous fistula or vascular graft (fistula or shunt)
Using an arteriovenous fistula or vascular graft for CKRT access requires specific precautions to protect the vascular access and reduce the risks of bleeding, thrombosis or shunt injury. The decision to use such access is based on its condition and the team’s assessment; it is not treated as a routine alternative to a central venous catheter [1].
Catheter lock solutions and catheter replacement — Catheter-Locking Solutions
The catheter lock solution is determined according to the catheter type, the approved lock concentration and institutional instructions. A trial of anticoagulation within the circuit does not imply that the catheter lock solution is the same or that it has the same clinical effect [1].
Heparin or trisodium citrate can be used as catheter lock solutions after catheter insertion and before starting CKRT, or during treatment interruptions.
Studies indicate that trisodium citrate is superior to heparin because it is associated with lower rates of bleeding, thrombosis and infection.
Routine use is not recommended for:
— Antibiotic-impregnated catheters.
— Topical antibiotics.
— Or antibiotic-containing catheter lock solutions.
Because they may promote:
— Fungal infection.
— And the development of antimicrobial resistance.
Catheters are not replaced on a routine schedule solely to prevent infection; institutional guidelines are followed when infection, obstruction or dysfunction is suspected [3]. When it becomes clear that recovery of kidney function sufficient to discontinue KRT is not imminent, consideration should be given to placing:
A permanent dialysis catheter, such as a tunnelled cuffed haemodialysis catheter or a Demers catheter.
Passing a guidewire again (rewiring) through a temporary haemodialysis catheter when it malfunctions is often ineffective. In many cases, placing a catheter at a new site may save more time and improve catheter function.
References
[1] KDIGO. Clinical Practice Guideline for Acute Kidney Injury. Kidney Int Suppl. 2012;2:1–138. https://kdigo.org/wp-content/uploads/2016/10/KDIGO-2012-AKI-Guideline-English.pdf.
[2] Parienti JJ, et al. Femoral vs jugular venous catheterization and risk of nosocomial events in adults requiring acute renal replacement therapy: a randomized controlled trial. JAMA. 2008;299(20):2413–2422. doi:10.1001/jama.299.20.2413.
[3] CDC. Guidelines for the Prevention of Intravascular Catheter-Related Infections. https://www.cdc.gov/infection-control/hcp/intravascular-catheter-related-infection/.