Identifying Hemodialysis Catheter Recirculation Using Effective Ionic Dialysance

Abstract

Vascular catheter use for dialysis remains highly prevalent, however, it is frequently adversely affected by access recirculation (AR). We previously reported the utility of effective ionic dialysance (EID)/blood flow rate (Qb) ratio in identifying significant (>5%) AR in arteriovenous (AV) fistulas (Mohan et al ASAIO J 56:427-433, 2010). We present data from 58 patients, receiving hemodialysis via venous catheters (85% tunneled cuffed catheters) who underwent intermittent monitoring for AR with the saline dilution technique (Transonic HD02 monitor) and had EID and Qb measurements from Diascan biosensor in the Gambro Phoenix dialysis machine available. Among the 193 hemodialysis sessions studied, 74 instances of significant access recirculation (sAR) were identified. A higher incidence of sAR occurred with temporary catheters and catheters in the femoral vein. We report a significant correlation between the EID/Qb ratio and AR in addition to demonstrating the predictive utility of the ratio for identifying dysfunction catheters with sAR (area under the receiver operator characteristic curve of 0.86 with a sensitivity of 79% and a specificity of 76% at an EID/Qb ratio of ≤ 0.60). Our data demonstrate the utility of the EID/Qb ratio as an indicator of sAR in dialysis catheters albeit at a different threshold than that seen with AV fistulae.

Integrating Real Time Data to Improve Outcomes in Acute Kidney Injury

“…These methods can eliminate the need for blood sampling, ensure accuracy and consistency of delivered dose, detect access recirculation and enable quality assurance [48]. Ionic dialysance, for example, can accurately and constantly detect changes in clearance [5] and problems with recirculation [7] without intermittent blood sampling. When connected to EHRs, this continuous clearance monitoring can lead to real-time decision support thus facilitating the adjustment of dialysis prescriptions and timely interventions [7,44].…”

“…Matching this with cardiac output may provide further improvements [41]. Current device technology is sufficiently advanced as to capture treatment conductivity, urea kinetics, blood volume changes, thermal balance and access recirculation, among other variables [2,42,43], yet they are not integrated - despite the potential to result in improved outcomes [7,44,45,46,47]. Currently available techniques for adequacy assessment include conductivity-based methods, urea sensors and spectrophotometric methods [3,4].…”

“…Ionic dialysance, for example, can accurately and constantly detect changes in clearance [5] and problems with recirculation [7] without intermittent blood sampling. When connected to EHRs, this continuous clearance monitoring can lead to real-time decision support thus facilitating the adjustment of dialysis prescriptions and timely interventions [7,44]. Similarly, ultraviolet absorbance in dialysate can help monitor dose delivery, allowing for timely prescription adjustments [3,49].…”

“…The treatment generates significant amounts of data, including pressure readings at various time points and locations in the circuit, changes in clearance and ultrafiltration rates. More recent technologies [2] have allowed for real-time measurement of delivered dialysis dose [3,4,5], estimates of access health [6] and the presence of recirculation [7]. In conjunction with ongoing hemodynamic monitoring, these features provide an opportunity to intervene and improve outcomes for patients requiring RRT [8].…”

Knowing What We Do and Doing What We Should: Quality Assurance in Hemodialysis

“…Accordingly, an objective and unbiased reporting of dialysis dose can be provided - accounting for every treatment. Additionally, online dialysance monitoring may assist in diagnosing problems such as needle reversal and vascular access malfunction [46,47]. Trending machine-measured dialysance over time may provide ‘continuous vascular access surveillance', alerting staff allowing them to intervene at an early time point, potentially reducing the risk of access complications.…”