RecruitingNCT06659835DIAMINOUpdated May 25, 2025

Amino Acid Loss During Continuous Renal Replacement Therapy

An observational study in Renal Insufficiency and Kidney Failure, sponsored by Medical University of Vienna. Recruiting at 1 site in Austria. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-05-25.

Sponsored by Medical University of Vienna · Observational

From the registry’s dates

Started Feb 2025; still recruiting 1 year 8 months later.

Study type: Observational
Model: Cohort
Time perspective: Prospective
Enrollment: 30
Ages: 18 Years and older
Sex: All

Study summary

The goal of this observational study is to learn about amino acid loss during continuous renal replacement therapy and plasma amino acid levels in intensive care patients. The main questions it aims to answer are:

What amount of amino acids is lost over the duration of continuous renal replacement therapy? How do amino acid plasma concentrations change over time in patients with and without continuous renal replacement therapy?

Amino acid concentrations will be measured in the effluent and in the plasma of patients receiving continuous renal replacement therapy as part of their regular medical care. In addition, plasma concentrations of amino acids will be studied in patients without renal replacement therapy.

Read the detailed description

In order to quantify the amount of amino acids lost via the continuous renal replacement (CRRT) machine, it is warranted to measure amino acid concentrations in the blood and effluent over the entire treatment period.

To this end, 20 intensive care patients will be examined throughout the entire duration of CRRT as part of this exploratory non-interventional study. Additionally, 10 intensive care patients without renal replacement therapy will be enrolled. In the CRRT-group amino acid loss through the effluent will be measured at different time points. Amino acid plasma concentrations will be determined in both groups. Amino acid urine concentration, nitrogen balance, as well as blood urea nitrogen, creatinine and albumin in the plasma will be measured as secondary outcome parameters. Additionally, observations regarding nutritional status and mobility (indirect calorimetry, bioimpedance analysis, ultrasound muscle and adipose tissue thickness, strength and mobility scoring) will be analyzed as exploratory secondary outcomes.

Duration of CRRT, length of intensive care and hospital stay as well as mortality will be monitored.

High-performance liquid chromatography fluorescence as well as liquid chromatography-mass spectrometry will be performed to measure amino acid concentrations in plasma, effluent and urine.

To answer the primary research question, change in amino acid plasma concentrations and effluent loss between treatment start and day 4 of continuous renal replacement therapy will be analysed using a two-sided Wilcoxon signed rank test.

Conditions studied

Renal Insufficiency
Kidney Failure

Browse trials for

Renal Insufficiency 1,995

Keywords

amino acid
continuous renal replacement therapy
effluent loss

In context

Renal Insufficiency

1,995 studies on the registry are indexed under Renal Insufficiency; 173 are open to participants now.

This study's planned enrollment of 30 is below the median of 149 across 394 observational studies indexed under Renal Insufficiency.

Browse Renal Insufficiency studies →

Lead sponsor

Medical University of Vienna is the lead sponsor of 1,076 studies on the registry; 177 are open to participants now.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: No
Sampling method: Probability sample

Study population

This study will enroll 30 intensive care patients: 20 patients receiving continuous renal replacement therapy and 10 patients without renal replacement therapy. The study will be carried out at the Medical University of Vienna at a 16-bed intensive care unit admitting patients after cardiothoracic and major vascular surgery.

Inclusion criteria

Postoperative ICU patients
Age ≥ 18 years
Patients on enteral or/and parenteral nutrition given according to internal standard operating procedure

A) CRRT group:

CRRT treatment planned; all types of CRRT (continuous veno-venous hemodialysis (CVVHD), continuous veno-venous hemodiafiltration (CVVHDF), continuous veno-venous hemofiltration (CVVH))

B)Non-CRRT group:

no current or previous (\<30 days) continuous or intermittent RRT
no chronic kidney disease stage G3-G5

Exclusion criteria

Exclusion criteria:

Preoperative intensive care patients
Patients with liver cirrhosis stage 1-3 according to the Child-Pugh classification
Patients with acute liver failure

Study design

Observational model: Cohort
Time perspective: Prospective
Enrollment: 30 participants (estimated)
Patient registry: No
Biospecimen retention: Samples with dna

Groups and cohorts

CRRT group
intensive care patients with continuous renal replacement therapy
non-CRRT group
intensive care patients without renal replacement therapy

What researchers measure

Primary outcomes

Amino acid effluent loss
Change of effluent loss of amino acids from start of continuous renal replacement therapy to day 4
Time frame: CRRT start, day 4 of continuous renal replacement therapy
Amino acid plasma concentration CRRT group
Change of plasma concentration of amino acids from start of continuous renal replacement therapy to day 4
Time frame: day 0, day 4 of continuous renal replacement therapy
Amino acid plasma concentration non-CRRT group
Change of plasma concentration of amino acids from the preoperative day to postoperative day 4 or to the last measurement at the intensive care unit, whichever is earlier
Time frame: preoperative day/enrollment to postoperative day 4

Secondary outcomes

Time course of effluent loss of amino acids over all measured time points
Time course of effluent loss of amino acids over all measured time points
Time frame: duration of continuous renal replacement therapy, maximum 30 days
Time course of plasma concentration of amino acids over all measured time points
Time course of plasma concentration of amino acids over all measured time points
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Urine concentration of amino acids over treatment period
Urine concentration of amino acids over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Nitrogen balance
Nitrogen balance over treatment period
Time frame: duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Blood urea nitrogen
Blood urea nitrogen over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Creatinine
Creatinine in blood, effluent, urine over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Albumin
Albumin in blood, effluent, urine over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Total protein
Total protein in blood, effluent urine over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Vitamins
Vitamins (Vitamin B12, folate) in blood, effluent, urine over treatment period
Time frame: duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Trace elements
Trace elements (iron, iodide) in blood, effluent, urine over treatment period
Time frame: duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Indirect Calorimetry
Indirect calorimetry over treatment period
Time frame: duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Bioimpedance analysis
Bioimpedance analysis over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Ultrasound Muscle and Adipose Tissue Thickness
ultrasound to measure muscle and adipose tissue thickness over treatment period
Time frame: preoperative if recruited preoperatively, duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Muscle Strength
muscle strength assessment (Medical Research Council Scale for Muscle Strength) over treatment period
Time frame: duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Mobility
mobility assessment (Surgical Intensive Care Unit Optimal Mobilisation Score) over treatment period
Time frame: duration of continuous renal replacement therapy (CRRT group) or length of ICU stay (non CRRT-group), maximum 30 days
Duration of Continuous Renal Replacement Therapy
duration of Continuous Renal Replacement Therapy
Time frame: duration of Continuous Renal Replacement Therapy (CRRT group), through study completion on average 10 days
Length of stay
Length of ICU stay
Time frame: length of ICU and hospital stay, through study completion maximum 1 year
Mortality
mortality during ICU and hospital stay
Time frame: length of ICU and hospital stay, through study completion maximum 1 year

Study locations

1 of 1 sites recruiting

Medical University of Vienna
Vienna, 1090, Austria
- Sarah Yadavalli, Dr. · Contact · sarah.yadavalli@meduniwien.ac.at · +43 067761632558
- Arabella Fischer, Dr. · Contact · arabella.fischer@meduniwien.ac.at
- Arabella Fischer, Dr. · Principal investigator
Recruiting

References and documents

Publications

Maxvold NJ, Smoyer WE, Custer JR, Bunchman TE. Amino acid loss and nitrogen balance in critically ill children with acute renal failure: a prospective comparison between classic hemofiltration and hemofiltration with dialysis. Crit Care Med. 2000 Apr;28(4):1161-5. doi: 10.1097/00003246-200004000-00041. PubMed 10809299 ↗
Kihara M, Ikeda Y, Fujita H, Miura M, Masumori S, Tamura K, Yabana M, Takagi N, Umemura S, Ishii M. Amino acid losses and nitrogen balance during slow diurnal hemodialysis in critically ill patients with renal failure. Intensive Care Med. 1997 Jan;23(1):110-3. doi: 10.1007/s001340050299. PubMed 9037649 ↗
Berger MM, Shenkin A, Revelly JP, Roberts E, Cayeux MC, Baines M, Chiolero RL. Copper, selenium, zinc, and thiamine balances during continuous venovenous hemodiafiltration in critically ill patients. Am J Clin Nutr. 2004 Aug;80(2):410-6. doi: 10.1093/ajcn/80.2.410. PubMed 15277163 ↗
Stapel SN, de Boer RJ, Thoral PJ, Vervloet MG, Girbes ARJ, Oudemans-van Straaten HM. Amino Acid Loss during Continuous Venovenous Hemofiltration in Critically Ill Patients. Blood Purif. 2019;48(4):321-329. doi: 10.1159/000500998. Epub 2019 Jul 10. PubMed 31291614 ↗
Story DA, Ronco C, Bellomo R. Trace element and vitamin concentrations and losses in critically ill patients treated with continuous venovenous hemofiltration. Crit Care Med. 1999 Jan;27(1):220-3. doi: 10.1097/00003246-199901000-00057. PubMed 9934919 ↗
Sundstrom Rehal M, Liebau F, Tjader I, Norberg A, Rooyackers O, Wernerman J. A supplemental intravenous amino acid infusion sustains a positive protein balance for 24 hours in critically ill patients. Crit Care. 2017 Dec 6;21(1):298. doi: 10.1186/s13054-017-1892-x. PubMed 29212550 ↗
Bellomo R, Tan HK, Bhonagiri S, Gopal I, Seacombe J, Daskalakis M, Boyce N. High protein intake during continuous hemodiafiltration: impact on amino acids and nitrogen balance. Int J Artif Organs. 2002 Apr;25(4):261-8. doi: 10.1177/039139880202500403. PubMed 12027135 ↗
Chua HR, Bellomo R. Nutritional Management of Patients Treated with Continuous Renal Replacement Therapy. Elsevier Inc.; 2013. https://doi.org/10.1016/B978-0-12-391934-2.00037-0
Fischer A, Hertwig A, Hahn R, Anwar M, Siebenrock T, Pesta M, Liebau K, Timmermann I, Brugger J, Posch M, Ringl H, Tamandl D, Hiesmayr M; USVALID Collaboration Group. Validation of bedside ultrasound to predict lumbar muscle area in the computed tomography in 200 non-critically ill patients: The USVALID prospective study. Clin Nutr. 2022 Apr;41(4):829-837. doi: 10.1016/j.clnu.2022.01.034. Epub 2022 Feb 11. PubMed 35263692 ↗
Fischer A, Spiegl M, Altmann K, Winkler A, Salamon A, Themessl-Huber M, Mouhieddine M, Strasser EM, Schiferer A, Paternostro-Sluga T, Hiesmayr M. Muscle mass, strength and functional outcomes in critically ill patients after cardiothoracic surgery: does neuromuscular electrical stimulation help? The Catastim 2 randomized controlled trial. Crit Care. 2016 Jan 29;20:30. doi: 10.1186/s13054-016-1199-3. PubMed 26825278 ↗
Kasotakis G, Schmidt U, Perry D, Grosse-Sundrup M, Benjamin J, Ryan C, Tully S, Hirschberg R, Waak K, Velmahos G, Bittner EA, Zafonte R, Cobb JP, Eikermann M. The surgical intensive care unit optimal mobility score predicts mortality and length of stay. Crit Care Med. 2012 Apr;40(4):1122-8. doi: 10.1097/CCM.0b013e3182376e6d. PubMed 22067629 ↗
Jonckheer J, Vergaelen K, Spapen H, Malbrain MLNG, De Waele E. Modification of Nutrition Therapy During Continuous Renal Replacement Therapy in Critically Ill Pediatric Patients: A Narrative Review and Recommendations. Nutr Clin Pract. 2019 Feb;34(1):37-47. doi: 10.1002/ncp.10231. Epub 2018 Dec 20. PubMed 30570180 ↗
Oddoye EA, Margen S. Nitrogen balance studies in humans: long-term effect of high nitrogen intake on nitrogen accretion. J Nutr. 1979 Mar;109(3):363-77. doi: 10.1093/jn/109.3.363. PubMed 430238 ↗
Bernardi MH, Schmidlin D, Ristl R, Heitzinger C, Schiferer A, Neugebauer T, Wrba T, Hiesmayr M, Druml W, Lassnigg A. Serum Creatinine Back-Estimation in Cardiac Surgery Patients: Misclassification of AKI Using Existing Formulae and a Data-Driven Model. Clin J Am Soc Nephrol. 2016 Mar 7;11(3):395-404. doi: 10.2215/CJN.03560315. Epub 2016 Jan 22. PubMed 26801479 ↗

Individual participant data

Plan to share: Undecided

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on May 25, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT06659835
Lead sponsor: Medical University of Vienna
Collaborators: Karolinska Institutet
Responsible party: Arabella Fischer, MD (Principal investigator, Medical University of Vienna) — Principal investigator
First posted: Oct 26, 2024
Start date: Feb 8, 2025
Primary completion: Sep 2026 (estimated)
Completion: Dec 2026 (estimated)
Last update: May 25, 2025

Study contacts

Sarah Yadavalli, Dr.

Contact

sarah.yadavalli@meduniwien.ac.at

+43 67761632558

Arabella Fischer, Dr.

Contact

arabella.fischer@meduniwien.ac.at

Sarah Yadavalli, Dr.

principal investigator · Medical University of Vienna

Arabella Fischer, Dr.

principal investigator · Medical University of Vienna

Andrea Laßnigg, Prof.

study director · Medical University of Vienna

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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