Sensors and Hybrid Therapies: A New Approach with Automated Citrate Anticoagulation

Abstract

Background: Hybrid therapies use intermittent hemodialysis (IHD) machines adapted to provide prolonged intermittent or continuous renal replacement therapy in the intensive care unit (ICU). Despite the low cost, hybrid therapy use is limited warranting a novel approach. Methods: The literature was reviewed for limitations of hybrid protocols, use of regional citrate anticoagulation (RCA) on hybrid systems and sensors for IHD and hybrid therapy. The novel hybrid program in the authors’ institution is presented as a plausible future direction for the modality. Results: Hybrid therapies are limited by access flow and clotting alarms. Technology limitations render many IHD sensors inoperable at low dialysate flow. A synergy with RCA allows a novel, safe approach with low blood flows and high dialysate flows with alarm- and clotting-free operation and all commercial IHD sensors functional. Conclusion: The low cost, ease of use, safety and efficacy of hybrid therapy with near-automated RCA may lead to rapid expansion of this form of ICU renal support.

Efficacy and Safety of a Citrate-Based Protocol for Sustained Low-Efficiency Dialysis in AKI Using Standard Dialysis Equipment

“…In this regard, it is likely that SLED with nearautomated regional citrate anticoagulation protocols optimized for very low blood flows and low citrate loads (46), as well as the availability of routine citrate measurements (47), could represent important developments, in order to improve the safety and efficacy of the citrate-based "hybrid" extracorporeal modalities.…”

The future of critical care: renal support in 2027

“…Moreover, some of these studies involved machines capable of semi-automated RCA delivery in which citrate infusion rates are modulated by device software, at least to some extent [47]. We predict that CRRT machines will provide more fully automated RCA by 2027, as has been proposed for other acute RRT modalities [48]. Finally, we foresee that the use of heparin as an anticoagulant for CRRT will be markedly reduced by 2027, due to its hemorrhagic risks in the CRRT population.…”

Online Hemoglobin and Oxygen Saturation Sensing During Continuous Renal Replacement Therapy with Regional Citrate Anticoagulation

“…The stand-alone OHOS monitor we use (Crit-line, Hemametrics, Waltham, mA) can easily be deployed predialyzer into the extracorporeal circuit of the SLED-RCA system (Figure 1). 8,9 The monitor displays the Hct or the Hb level, the blood O 2 saturation, and the trend in the percentage change in relative blood volume (RBV) calculated from the percentage differences between the starting and current Hb level. A negative percentage change in RBV indicates that the ultrafiltration rate is faster than the patient's intravascular volume refill rate (or that the patient has a rising Hb because of transfusion).…”

“…Optical hemoglobin and oxygen saturation sensor (OHOS) monitor could be deployed predialyzer into the extracorporeal circuit of continuous renal replacement therapy (CRRT) systems. Twenty-four hour sustained low-efficiency dialysis (SLED) with regional citrate anticoagulation (RCA) is a therapy that incorporates a stand-alone commercial OHOS into the extracorporeal circuit 8,9 and maintains the overall reliability of hemoglobin (Hb) and oxygen (O 2 ) saturation sensing.…”