Early versus late initiation of renal replacement therapy in critically ill patients with acute kidney injury (The ELAIN-Trial): study protocol for a randomized controlled trial

Background Acute kidney injury remains a common complication in critically ill patients and despite multiple trials and observational studies, the optimal timing for initiation of renal replacement therapy is still unclear. The early versus late initiation of renal replacement therapy in critically ill patients with acute kidney injury (ELAIN) study is a randomized, single-center, prospective, two-arm, parallel group trial to reduce mortality in patients with severe acute kidney injury. We describe the study design and discuss aspects of the need for a trial in this patient cohort. Methods/design Our plan is to randomize critically ill patients with acute kidney injury to ‘early’ or ‘late’ initiation of renal replacement therapy according to stage 2 and 3 of the KDIGO classification using a specific trial protocol. We plan to guide data collection and analysis using pre-existing definitions and testing. The primary endpoint is overall survival in a 90-day follow-up period. Secondary endpoints include 28-day, 60-day, 90-day and 1-year all-cause mortality, recovery of renal function, ICU and hospital length-of-stay. The primary analysis will be an intention-to-treat analysis; secondary analyses include treated analyses. We will also specify rules for handling data and determining outcome. Discussion Several challenges for study design and execution can be seen in our trial, and it should generate results that will inform and influence the practice of renal replacement therapy in critically ill patients with acute kidney injury. Trial registration German Clinical Trials Register: DRKS00004367 (www.germanctr.de); 28 May 2013. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1249-9) contains supplementary material, which is available to authorized users.

cipal investigator is Prof. Dr. Alexander Zarbock (Department of Anesthesiology, Intensive Care and Pain Medicine, University of Münster).

Information
Why do we perform this study ? We perform this study to evaluate the optimal timing for the initiation of renal replacement therapy in critically ill patients with acute kidney injury.

What treatment do I receive?
We want to examine whether the early initiation of renal replacement therapy shows a benefit comparing to late initiation. If we diagnose an acute kidney injury and you are willing to participate in this study you will be assigned to one of the two treatment arms. Renal replacement therapy will be initiated either early or late.

How is the study process and what do I have to consider if I participate in this study?
At the time of study inclusion we will evaluate your medical history and you will get a comprehensive medical examination. Acute kidney injury is diagnosed through several clinical parameters such as an increase in serum-creatinine in the blood and/or a decrease in urinary output. Additionally, we will analyze a biomarker (NGAL; neutrophil gelatinase-associated lipocalin) in the blood which gives us a more detailed specification on acute kidney injury. The clinical condition with regard to acute kidney injury needs to be considered due to our inclusion criteria. It depends on the results of this comprehensive examination whether your clinical condition allows us to include you to the study. Subsequently, if you give your consent, you will be randomly assigned to one of the two treatment arms. If you are randomized to the early group renal replacement therapy will be initiated as soon as possible. If you are randomized to the late group the timing of initiation of renal replacement therapy cannot be appointed. The course of acute kidney injury depends on numerous individual factors in critically ill patients. The time interval until fulfilling the criteria for the late group can differ between hours and days.
If you participate in this study we will collect blood (3 ml) and urine (3 ml) samples at five different time points (at the time of inclusion, day 1, 3, 5 of renal replacement therapy and 1 day after cessation of renal replacement therapy) for additional biomarker analysis. Samples will be collected using routinely placed catheters, additional vascular punctures are not necessary.
Clinical examinations, medical interventions and ascertained parameters are fixed components of your routinely treatment. The intensive care treatment does not differ between the two groups except the time of the initiation of renal replacement therapy. One year after inclusion we will contact you to ask for your physical condition.

Care of samples
The samples for the additional analyses will be labeled pseudonymously. Pseudonymous means that we do not use your name or your initials for the labeling. We will use a number code for the samples. After the analyses, which will be performed in our own laboratories, we will keep the samples for a maximum of ten years and then destroy them.

Do I have a personal benefit by participating in this study?
If you are allocated to the early group, this may improve the treatment of your disease. As it is not proved whether the early initiation of renal replacement therapy is associated with a clinical advantage, the participation in this study may not have the desired benefit. If you are allocated to the late group, your prospects for treatment will not differ between participation and no participation in the study. However, the results of this study may contribute to the improvement of the therapy of critically ill patients with acute kidney injury.

What risks are associated with the participation in the study?
With this study we want to analyze whether the early initiation of renal replacement therapy is associated with a clinical benefit in critically ill patients with acute kidney injury compared to late initiation. Renal replacement therapy will be performed using Citrate anticoagulation, a widely accepted and used method. For this, a double lumen venous catheter needs to be inserted and blood is extracted through one of the two lumen. The extracted blood runs through dialysis, the uremic agents are removed and brought back to the body through the second lumen. As the blood runs through extraneous surface, anticoagulation with citrate is performed to avoid clotting. The effect of citrate is reversed by giving calcium before entering the systemic circulation in order to avoid adverse events. The following complications may occur: catheter insertion problems (bleeding, infection, tissue injury), blood pressure drops caused by blood extraction, electrolyte imbalances. All these possible complications are considered low as intensive care treatment means close monitoring of the hemodynamic and laboratory parameters and quick response to the mentioned conditions. It is expected however that patients in both groups will need dialysis; the only difference is the timing of initiation of renal replacement therapy. For most patients, the participation in this study will not come with extra risks.

What happens if I do not participate in this study?
If you do not participate in this study you receive the routinely medical care according to the current medical standards. Important: You are able to terminate your study participation at any time point during the study period without disadvantages for your medical treatment.

Who may participate in this study?
You are not allowed to participate in this study if you are currently participating or did participate until recently (30 days) in another trial. Further, you are not able to participate in this study if you meet one of the following criteria: • Pregnancy • Chronic kidney disease (glomerulonephritis, interstitial nephritis, vasculitis) • Previous renal replacement therapy • Liver cirrhosis • HIV-infection • Hematologic diseases The study investigator will proof the exclusion criteria and answer your questions.

Who decides whether I get eliminated from this study?
You can terminate your study participation at any time point during the study period without any explanation. This will not lead to any disadvantages in your medical treatment.
In certain circumstances the study investigator will decide to terminate your study participation and you will not have any influence on this decision. This may be caused by the following: • Your study participation is medically unjustifying.
• The complete trial is cancelled.

Do I get information about new findings during the study?
If we have any new findings that may be related to a change in your personal therapeutic strategy then you obviously will get information on that.

Does the study participation arise any costs?
No, there are no additional costs resulting from study participation.

Am I medically insured?
Yes, we have a health insurance for study participants. By request, you can get the scope of the insurance cover. Any health impairment that may be related to the study participation needs to be reported immediately to the insurance to protect your insurance cover. The study investigator needs to be informed immediately about any change in your medical condition. He will evaluate if this change may be related to the study and he will help you with the report to the insurance. The status will be documented and clarified. This is of high interest because otherwise you may loose your insurance cover. By request you will obviously receive a copy of the insurance conditions.

What happens to the data?
Your medical history and personal information will be documented pseudonymously. We will use a number code for your data to keep them safe and only staff members working on this trial have access to this code. The staff is obligated to maintain confidentiality. A decoding is only allowed on the legally prescribed cases. Details can be seen in the informed consent. 1) I agree that the Department of Anesthesiology, Intensive Care and Pain Medicine may record data about my medical condition, on paper as well as on electronic case report forms, for this clinical trial. Where required, data may be transmitted pseudonymously: a. In case of adverse events: to the ethics board committee b. Further, I agree that authorized and confidential representatives of the university of Münster may take insight to personalized data if this is necessary to prove a proper implementation of the study. For this I release the study investigator from the secrecy obligation. 2) I agree that my data are kept for ten years after termination or completion of the study as law for drug trials prescribes it. Data will be deleted after ten years.

If you have any questions
I have been informed that the participation in this trial is voluntary and that I may withdraw my consent at any time of the study period without any disadvantages.

I declare that my participation in the ELAIN-trial is completely voluntary.
I received a copy of the information letter and consent as well as a copy of the general insurance conditions. One copy remains at the trial center.
______________________________________________________________________________ Name of patient __________ _______________________________ Date Signature of patient

Confirmation of person obtaining consent
The patient has been informed about nature, meaning and consequences of the participation in this trial (verbally and in writing) according to the legal regulations of the food and drug legislation. Questions have been sufficiently answered. The patient agreed voluntarily to participate in this trial. A copy of the information letter and consent was delivered to the patient.  about the study. I received the patient information related to this study and a copy of the signed statement of consent. I read and understood both documents. I was cleared up on aims, course, chances and risks of the study, my rights and obligations, the insurance cover and the voluntary nature of the participation in this study. I had the possibility to ask questions. These have been sufficiently answered. Additionally, these points have been addressed to: ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ It has been explained that during the study period there is an insurance that covers study related harms. I am obligated to contact immediately the study investigators if study related injuries occur. I am aware that I am able to withdraw my study agreement without giving any reasons (verbally or in writing), without having any disadvantages in my medical treatment.

Authorized representative -Informed Consent Declaration Prospective, randomized, clinical study for analyzing the influence of the timing of renal replacement therapy on the survival of critically ill patients with acute kidney injury (ELAIN-Trial)
Data safety I am aware that for this clinical study personalized data are being raised, especially the medical history and diagnostic findings, for further analysis. The use of the data is subjected to statutory provisions and needs my consent to participate in this study. 1) I agree that the Department of Anesthesiology, Intensive Care and Pain Medicine may record data about the medical condition, on paper as well as on electronic case report forms, for this clinical trial. Where required, data may be transmitted pseudonymously: a. In case of adverse events: to the ethics board committee b. Further, I agree that authorized and confidential representatives of the university of Münster may take insight to personalized data if this is necessary to prove a proper implementation of the study. For this I release the study investigator from the secrecy obligation. 2) I agree that my data are kept for ten years after termination or completion of the study as law for drug trials prescribes it. Data will be deleted after ten years.
I have been informed that the participation in this trial is voluntary and that I may withdraw my consent at any time of the study period without any disadvantages.
I declare that the above-mentioned patient will participate in the ELAIN Trial.
I received a copy of the information letter and consent as well as a copy of the general insurance conditions. One copy remains at the trial center. about the study. I received the patient information related to this study and a copy of the signed statement of consent. I read and understood both documents. I was cleared up on aims, course, chances and risks of the study, my rights and obligations, the insurance cover and the voluntary nature of the participation in this study. I had the possibility to ask questions. These have been sufficiently answered. Additionally, these points have been addressed to: ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________________ It has been explained that during the study period there is an insurance that covers study related harms. I am obligated to contact immediately the study investigators if study related injuries occur. I am aware that I am able to withdraw my study agreement without giving any reasons (verbally or in writing), without having any disadvantages in the medical treatment.
Data safety I am aware that for this clinical study personalized data are being raised, especially the medical history and diagnostic findings, for further analysis. The use of the data is subjected to statutory provisions and needs my consent to participate in this study. 1) I agree that the Department of Anesthesiology, Intensive Care and Pain Medicine may record data about the medical condition, on paper as well as on electronic case report forms, for this clinical trial. Where required, data may be transmitted pseudonymously: a. In case of adverse events: to the ethics board committee b. Further, I agree that authorized and confidential representatives of the university of Münster may take insight to personalized data if this is necessary to prove a proper implementation of the study. For this I release the study investigator from the secrecy obligation. 2) I agree that my data are kept for ten years after termination or completion of the study as law for drug trials prescribes it. Data will be deleted after ten years.
I have been informed that the participation in this trial is voluntary and that I may withdraw my consent at any time of the study period without any disadvantages.
I declare that the above-mentioned patient will participate in the ELAIN Trial.
I received a copy of the information letter and consent as well as a copy of the general insurance conditions. One copy remains at the trial center.

Confirmation of the attending physician
I confirm that due to the emergency situation the patient's informed consent cannot be provided. As soon as a legal representative is available, her/his consent will be obtained. If the patient regains her/his capacity for consent her/his consent will be obtained.
I handed a copy of the information declaration of study inclusion to the consultant physician.

_________________________________________
Place and date ______________________________________ ______________________________ Name of the attending physician Signature of the attending physician