Study protocol: the DOse REsponse Multicentre International collaborative initiative (DO-RE-MI)

Abstract

Introduction: Current practices for renal replacement therapy in intensive care units (ICUs) remain poorly defined. The DOse REsponse Multicentre International collaborative initiative (DO-RE-MI) will address the issue of how the different modes of renal replacement therapy are currently chosen and performed. Here, we describe the study protocol, which was approved by the Scientific and Steering Committees.

Methods: DO-RE-MI is an observational, multicentre study conducted in ICUs. The primary end-point will be the delivered dose of dialysis, which will be compared with ICU mortality, 28-day mortality, hospital mortality, ICU length of stay and number of days of mechanical ventilation. The secondary end-point will be the haemodynamic response to renal replacement therapy, expressed as percentage reduction in noradrenaline (norepinephrine) requirement. Based on the the sample analysis calculation, at least 162 patients must be recruited. Anonymized patient data will be entered online in electronic case report forms and uploaded to an internet website. Each participating centre will have 2 months to become acquainted with the electronic case report forms. After this period official recruitment will begin. Patient data belong to the respective centre, which may use the database for its own needs. However, all centres have agreed to participate in a joint effort to achieve the sample size needed for statistical analysis.

Conclusion: The study will hopefully help to collect useful information on the current practice of renal replacement therapy in ICUs. It will also provide a centre-based collection of data that will be useful for monitoring all aspects of extracorporeal support, such as incidence, frequency, and duration.

Figure 1

Flowchart of the DO-RE-MI observational study. All incident patients admitted to the intensive care unit (ICU) and requiring renal replacement therapy (RRT) will be followed up during RRT. At discharge, primary and secondary end-points will be recorded. All data will be entered in electronic case report form (CRF) and stored in a website [11]. The rectangles indicate the type of information that will be available from this study. ARF, acute renal failure; DO-RE-MI, DOse REsponse Multicentre International collaborative initiative; SAPS, Simplified Acute Physiology Score.

Figure 2

Examples of how the different case report forms will be applied. Four different cases are summarized, encompassing treatment interruption or end in relation to the compilation of case report forms (CRFs). Case 1 is the easiest case. The patient is admitted to the intensive care unit (ICU), is treated with renal replacement therapy (RRT), ends treatment and is discharged. The patient has a single CRF. In case 2 the patient is admitted and is treated with RRT, but this treatment is stopped for longer than 18 hours (this is defined as treatment end). However, the patient is later started on RRT again. A new CRF (even if the modality is the same) will need to be completed. In this case, the patient has two or more CRFs (as in the case of more than one treatment stoppages for longer than 18 hours). In case 3 the patient is admitted and is started on RRT, which is stopped for less than 18 hours (defined as interruption). The patient is then restarted and the compilation is continued on the same CRF. Case 4 is similar to case 3, with the important difference being related to the change in modality following treatment interruption. In this case, each change of modality will require a new CRF.

Figure 3

Mortality rate as a function of dialysis dose (expressed as urea clearance ml/min).

Figure 4

Power as a function of sample size.