KDIGO Clinical Practice Guideline for Acute Kidney Injury
Uncuffed nontunneled dialysis catheter vs a tunneled catheter: Recommendations and Rationale

• 5.4.1: We suggest initiating RRT in patients with AKI via an uncuffed nontunneled dialysis catheter, rather than a tunneled catheter. (2D)

Rationale

Since most early catheter-related infections have a cutaneous origin, tunneling the catheter under the skin together with a subcutaneous anchoring system, may reduce the risk of infection. Tunneling also increases mechanical stability of the catheter. On the other hand, the insertion of a tunneled cuffed catheter (TCC) is a cumbersome procedure that requires expertise (mostly performed by surgeons or interventional radiologists), time, and effort (mostly performed in the operating room or radiology department), thus potentially delaying initiation of RRT. The removal of TCCs is also technically more difficult.

A randomized trial compared the initial use of tunneled vs. nontunneled femoral catheters in 34 patients with AKI. Failure to insert the TCC occurred in four patients (12%) that were excluded from the final analysis. In the remaining 30 patients, those with tunneled catheters had an increased insertion time and more femoral hematomas, but also less dysfunction, fewer infectious and thrombotic complications, and a significantly better catheter survival.⁶³⁹ The small size of this study and the absence of an intention-to-treat analysis preclude firm conclusions (Suppl Table 33). In addition, the use of tunneled catheters for starting acute dialysis is not widespread practice.

Both the Centers for Disease Control (CDC) guidelines for prevention of catheter-related infections and the KDOQI guideline for vascular access in chronic dialysis patients recommend using a cuffed catheter for dialysis if a prolonged (e.g., > 1–3 weeks) period of temporary access is anticipated. ^640,641 In two recent large randomized trials, the mean duration of RRT for AKI was 12–13 days.^562,563 This probably does not justify the burden of an initial tunneled catheter in all patients with AKI receiving RRT. Rather, selected use of tunneled catheters in patients who require prolonged RRT is warranted.

No recommendation can be given regarding the optimal timing to change the nontunneled-uncuffed catheter to a more permanent access. It seems reasonable to create a more permanent access when recovery of kidney function is unlikely. The optimal timing should take into account the increased risk of infection with untunneled catheters, but also the practical issues related to the insertion of a tunneled catheter.

Several configurations of dialysis catheter lumen and tip have emerged over the years with no proven advantage of one design over another. The outer diameter varies between 11 and 14 French and it is self-evident that larger sizes decrease the risk of inadequate blood flow. In order to provide an adequate blood flow and reduce the risk of recirculation, the tip of the catheter should be in a large vein (see Recommendation 5.4.2). This means that the optimal length is 12–15 cm for the right internal jugular vein, 15–20 cm for the left internal jugular vein, and 19–24 cm for the femoral vein.^642-644

In PD, the Tenckhoff catheter, a soft, silicone rubber catheter with a polyester cuff, reduced early complications such as bowel perforation, massive bleeding, or leakage, and has become the standard for PD. Further modifications, including the use of swan-neck catheters, T-fluted catheters, curled intraperitoneal portions, dual cuffs, and insertion through the rectus muscle instead of the midline, have been made to reduce remaining complications such as peritonitis, exit/tunnel infection, cuff extrusion, obstruction, and dialysate leaks.^645,646 Blind placement has been largely replaced by surgical placement or placement guided by ultrasound/fluoroscopy, laparoscopy, or peritoneoscopy.^647-649 Continuous-flow PD dictates the need for an efficient dual-lumen catheter or two separate catheters with ports separated maximally.⁶⁴⁶ Outside the pediatric setting, no investigations have specifically looked at peritoneal catheters in the setting of AKI.