Effect of Dynamic Circuit Pressures Monitoring on the Lifespan of Extracorporeal Circuit and the Efficiency of Solute Removal During Continuous Renal Replacement Therapy

Abstract

Objective: To observe the effects of dynamic pressure monitoring on the lifespan of the extracorporeal circuit and the efficiency of solute removal during continuous renal replacement therapy (CRRT).Materials and Methods: A prospective observational study was performed at the West China Hospital of Sichuan University in the ICU. Analyses of the downloaded pressure data recorded by CRRT machines and the solute removal efficiencies, calculated by 2*Ce/(Cpre+Cpost), where Ce, Cpre, and Cpost are the concentrations of the effluent, pre-filter blood, and post-filter blood, respectively, were performed. Samples were collected at 0, 2, 6, 12, and 24 h when continuous veno-venous hemodiafiltration (CVVHDF) was used after the initiation of CRRT. Measurements in concentrations of creatinine, blood urea nitrogen, and β2-microglobulin in the plasma and effluent were recorded.Results: Extracorporeal circuits characterized by moderate-to-severe (M–S) access outflow dysfunction (AOD) events, defined as access outflow pressure less than or equal to −200 mmHg for more than 5 min, had shorter median lifespans with no anticoagulation (32.3 vs. 10.90 h, P = 0.001) compared with the no M–S AOD events group. The significant outcome also existed in regional citrate anticoagulation (RCA) (72 vs. 42.47 h, P = 0.02). Moreover, Cox regression analysis revealed that the lack of M–S AOD events, RCA, or CVVHDF independently prolonged the circuit lifespan. All tested solutes removal efficiencies started to decline at 12 h. Furthermore, efficiencies of all solutes removal dropped obviously at 24 h when TMP ≥ 150 mmHg.Conclusion: RCA and CVVHDF predicted a longer circuit lifespan. M–S AOD events were associated with a shorter circuit lifespan when RCA or no anticoagulant was used. Replacement of extracorporeal circuit could be considered when running time of filter lasted up to 24 h with TMP ≥ 150 mmHg.

Regional citrate anticoagulation vs systemic heparin anticoagulation for double‐filtration plasmapheresis

“…17,18 Maintaining extracorporeal circuit patency is important to maximize effective treatment time, avoid blood loss, lessen unnecessary nursing workload and reduce medical costs. 18 Although RCA has been shown to significantly increase circuit patency and reduce bleeding events when compared to systemic heparin anticoagulation in critically ill patients undergoing continuous kidney replacement therapy (CKRT), 14,[19][20][21] those results may not be applicable for patients undergoing DFPP due to differences in duration of therapy, the complexity of the circuit and coagulopathy associated with plasmapheresis. While previous studies have demonstrated RCA as a feasible option for anticoagulation for DFPP in both critically ill Abbreviations: DFPP, double-filtration plasmapheresis; Hep, systemic heparin anticoagulation; RCA, regional citrate anticoagulation.…”

“…Dysfunctional vascular access has been shown to be an independent risk factor for circuit survival in CKRT, [22][23][24] even with the use of RCA. 19 Patients with kidney transplants may not have a functioning vascular access and the use of a nonpermanent vascular catheter for TPE may be more common. Establishing a functional vascular access will be critical to ensuring good delivery of extracorporeal therapies.…”

“…Nonpermanent and dysfunctional vascular access was shown to be the risk factors for circuit clotting in our study. Dysfunctional vascular access has been shown to be an independent risk factor for circuit survival in CKRT, 22‐24 even with the use of RCA 19 . Patients with kidney transplants may not have a functioning vascular access and the use of a nonpermanent vascular catheter for TPE may be more common.…”