Patient clearance time (tp) with different vascular access types

Int J Artif Organs. 2013 Dec;36(12):853-60. doi: 10.5301/ijao.5000247. Epub 2013 Oct 2.

Abstract

Background/aims: The dialysis delivered dose is limited by the rate at which urea can be transferred from the different body compartments. The time needed to clear the peripheral compartments of the body has been called the patient clearance time (tp). The aim of the study was to compare delivered dialysis dose using the tp index between patients dialyzed through a permanent central venous catheter (CVC) and patients with an arteriovenous fistula (AVF).

Methods: The study included 48 stable hemodialyzed patients. Patients were classified into two groups according to their vascular access type. The first group included 24 patients dialyzed through a permanent CVC and the second group consisted of 24 patients with a mature AVF. The following parameters were calculated twice for each patient: tp, Kt/V adjusted for the tp.

Results: tp was lower in the AVF dialysis modality than in CVC (26 ± 7 vs. 42 ± 14 min, p<0.001) while the (eqKt/V)tp was higher in AVF than in CVC dialysis (1.36 ± 0.11 vs. 1.19 ± 0.13, p<0.001).

Conclusions: The patient clearance time is lower in AVF than in CVC dialysis, and this is accompanied by a higher delivered dialysis dose.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Arteriovenous Shunt, Surgical*
  • Catheterization, Central Venous*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Models, Biological
  • Renal Dialysis*
  • Time Factors
  • Treatment Outcome
  • Urea / blood

Substances

  • Urea