Chloride Transfer During Continuous Renal Replacement Therapy in the Intensive Care Unit: a Prospective Observational Cohort Study

NCT ID: NCT04755491

Last Updated: 2022-09-13

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 50 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2021-03-16
• Study Completion Date: 2022-08-24

Brief Summary

Acute kidney injury (AKI) is a frequently encountered complication in the intensive care unit (ICU), affecting on average 25 to 35% of patients. It is associated with an increased mortality, proportional to AKI severity. RRT induces important shifts of water and electrolytes. Thus, significant amount of chloride might unintentionally be transferred to patients.

Chloride is the main anion of the organism. It is involved in the regulation of numerous physiological processes. Thus, significant and rapid modification of chloride amount contained in the organism (as might be induced by renal replacement therapy) may be responsible for important, and potentially deleterious, consequences to critically ill patients.

Studies have shown that the administration of high amounts of chloride rich solutions (such as sodium chloride (NaCl) 0,9%) was associated with the development of hyperchloremic acidosis in a dose-dependent manner. This hyperchloremic acidosis could also be theoretically associated with deleterious physiological effects. However, the true clinical consequences of administration of high amounts of chloride rich solutions remains unclear. Their effect on mortality remains a matter of debate, the results of studies being very conflicting in that respect. Nevertheless, hyperchloremia itself and/or the rise of chloremia in the intensive care unit seems to be associated with increased mortality. Moreover, the impact of those chloride rich solutions on the development of acute kidney injury is also a subject of controversy, data from the literature being here again very conflicting.

A recent study already showed that continuous RRT (CRRT) techniques induce a significant transfer of sodium to patients benefiting from those techniques. In that study, the amount of sodium transferred depended mainly on the difference between patient's natremia and sodium concentration in dialysate and/or replacement fluid (usually higher than patient's natremia) used.

By analogy, it is likely that an occult transfer of chloride also happens during RRT, given the high chloride concentration of dialysate fluids (in continuous veno-venous dialysis, CVVD) and replacement fluids (in continuous veno-venous hemofiltration, CVVH), or when these 2 modalities are combined (continuous veno-venous hemodiafiltration, CVVHDF). Finally, the investigators suspect, although it remains undemonstrated so far, that the RRT technique (convective vs. diffusive) may influence this transfer, to an unknown extent. Nevertheless, this transfer and its potential determinants have never been studied yet.

If chloride overload (and its potential clinical consequences) induced by the administration of solutions such as NaCl 0,9% is being extensively studied, no study has ever focused on chloride transfer that may result from the use of renal replacement therapy. However, as mentioned above, it is very likely that such a chloride transfer to patients happens, and that its magnitude depends on different parameters such as RRT modality, RRT fluids characteristics, or patient's chloremia at the start of RRT.

The investigators conduct the present study to describe and compare the intensity of chloride transfer during the first 24 hours of renal replacement therapy by continuous veno-venous hemofiltration (CVVH), continuous veno-venous hemodialysis (CVVD),or continuous veno-venous hemodiafiltration (CVVHDF), and to determine if that transfer is more important with one or the other of those two techniques, in ICU patients affected with severe AKI requiring RRT. Secondary aims are to describe and compare the effects of chloride transfer under 3 RRT modalities (CVVD, CVVH and CVVHDF) on patient's outcome, organ failures, electrolyte and acid-base balance, fluid balance and hemodynamics. Finally, the investigators aim to develop a pharmacokinetic compartment model of chloride transfer during different modalities of RRT.

Conditions

Acute Kidney Injury

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Chloride transfer by continuous veno-venous hemofiltration

Chloride transfer over 24h of continuous veno-venous hemofiltration in mechanically ventilated ICU patients presenting with stage III AKI according to Kidney Disease: Improving Global Outcome (KDIGO) classification. Chloride concentrations will be measured in the serum, the urine, and the effluent of included patients every 4 to 6h from inclusion to H24.

Continuous veno-venous hemofiltration

Intervention Type: DEVICE

Treatment of KDIGO stage 3 AKI by CVVH, in which renal replacement therapy is applied using a convection technique (ultrafiltration). Indication, choice of CRRT modality, and CRRT settings are made by the clinician in charge, following international recommendations. The measurement of chloride transfer over 24h is performed during CVVH treatment.

Chloride transfer by continuous veno-venous hemodialysis

Chloride transfer over 24h of continuous veno-venous hemodialysis in mechanically ventilated ICU patients presenting with stage III AKI according to Kidney Disease: Improving Global Outcome (KDIGO) classification. Chloride concentrations will be measured in the serum, the urine, and the effluent of included patients every 4 to 6h from inclusion to H24.

Continuous veno-venous hemodialysis

Intervention Type: DEVICE

Treatment of KDIGO stage 3 AKI by CVVD, in which renal replacement therapy is applied using a diffusion technique (dialysis). Indication, choice of CRRT modality, and CRRT settings are made by the clinician in charge, following international recommendations. The measurement of chloride transfer over 24h is performed during CVVD treatment.

Chloride transfer by continuous veno-venous hemodiafiltration

Chloride transfer over 24h of continuous veno-venous hemodiafiltration in mechanically ventilated ICU patients presenting with stage III AKI according to Kidney Disease: Improving Global Outcome (KDIGO) classification. Chloride concentrations will be measured in the serum, the urine, and the effluent of included patients every 4 to 6h from inclusion to H24.

Continuous veno-venous hemodiafiltration

Intervention Type: DEVICE

Treatment of KDIGO stage 3 AKI by CVVHDF, in which renal replacement therapy is applied using a combination of diffusion technique (dialysis) and convection technique (ultrafiltration). Indication, choice of CRRT modality, and CRRT settings are made by the clinician in charge, following international recommendations. The measurement of chloride transfer over 24h is performed during CVVHDF treatment.

Interventions

Continuous veno-venous hemofiltration

Treatment of KDIGO stage 3 AKI by CVVH, in which renal replacement therapy is applied using a convection technique (ultrafiltration). Indication, choice of CRRT modality, and CRRT settings are made by the clinician in charge, following international recommendations. The measurement of chloride transfer over 24h is performed during CVVH treatment.

Intervention Type: DEVICE

Continuous veno-venous hemodialysis

Treatment of KDIGO stage 3 AKI by CVVD, in which renal replacement therapy is applied using a diffusion technique (dialysis). Indication, choice of CRRT modality, and CRRT settings are made by the clinician in charge, following international recommendations. The measurement of chloride transfer over 24h is performed during CVVD treatment.

Intervention Type: DEVICE

Continuous veno-venous hemodiafiltration

Treatment of KDIGO stage 3 AKI by CVVHDF, in which renal replacement therapy is applied using a combination of diffusion technique (dialysis) and convection technique (ultrafiltration). Indication, choice of CRRT modality, and CRRT settings are made by the clinician in charge, following international recommendations. The measurement of chloride transfer over 24h is performed during CVVHDF treatment.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Adult patients (age > 18 years) affiliated to a social security regimen.
• Presenting with stage III AKI according to Kidney Disease: Improving Global Outcome (KDIGO) classification28.
• Treated with continuous RRT (CVVH or CVVD or CVVHDF) for less than 24 hours, whatever the method used.
• Mechanically ventilated at the time of inclusion in the study.

Exclusion Criteria

• Patients on chronic hemodialysis / peritoneal dialysis.
• Patients on extracorporeal membrane oxygenation
• Patients on intermittent hemodialysis (acute or chronic)
• RRT initiated for a different reason than stage III AKI according to Kidney Disease: Improving Global Outcome (KDIGO) classification
• Withholding of life sustaining treatment concerning RRT, mechanical ventilation or cardiopulmonary resuscitation.
• Patients whose life expectancy is lower than 24 hours
• Patients under guardianship or another juridical protection
• Patient's or next of kin opposition to participate
• Patients previously included in the study

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Hospices Civils de Lyon

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Laurent BITKER, MD, PhD

Role: PRINCIPAL_INVESTIGATOR

Hospices Civils de Lyon

Locations

Hôpital de la Croix-Rousse (Hospices Civils de Lyon) / Médecine Intensive - Réanimation

Lyon, , France

Countries

France

References

Chivot M, Bellomo R, Deniel G, Richard JC, Bitker L. Chloride Mass Transfers during Continuous Veno-Venous Hemodialysis with Regional Citrate Anticoagulation: Effects of Additional Ultrafiltration and Hamburger's Effect. Blood Purif. 2025;54(7):404-412. doi: 10.1159/000546322. Epub 2025 May 28.

Reference Type: DERIVED

PMID: 40435983 (View on PubMed)

Other Identifiers

69HCL20_1055

Identifier Type: -

Identifier Source: org_study_id