The CIRE Study (CItrate REcirculation Study)

Study Overview
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Brief Summary
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The aim of this study is to determine the effects of AV port reversal (AVPR) on recirculation, clearance, post-filter ionized calcium and subsequently citrate dosing.

Detailed Description
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Rationale: AV port reversal (AVPR) has been demonstrated to increase recirculation in venous catheters used in ICU for CVVH. The effects of this frequently used manoeuvre have not been described in the setting of CVVH using regional citrate anticoagulation. Objective: The aim of this study is to determine the effects of AVPR on recirculation, clearance, post-filter ionized calcium and subsequently citrate dosing. Study design and methods: Open trial studying the effect of AVPR in patients undergoing citrate CVVH. After measurement in standard catheter configuration, AVPR is performed after which effects on catheter recirculation, clearance, citrate dosing and post-filter ionized calcium (iCa) are monitored. Sample sites: Arterial line, arterial (pre-filter) port, postfilter port (after postdilution and calcium compensation), effluent sample. All flow rates to be noted. Study population: Twelve patients admitted to intensive care, requiring continuous renal replacement therapy (CRRT) for AKI. Patients are preferably anuric and have achieved good metabolic control under CVVH before inclusion in the study.

Official Title
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Effects of AV Port Reversal in Citrate CVVH - The CIRE Study (CItrate REcirculation Study)

Conditions
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Acute Kidney Injury

Intervention / Treatment
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* Other: AV port reversal


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Critically ill patients requiring CRRT for AKI (RIFLE criteria) Written informed consent from the patient or legal representative No AV port reversal had taken place before inclusion in the study Diuresis is minimal or the patient is anuric so that effects of changes in clearance as a consequence of diuresis are minimalized and do not influence study outcomes. The patient has undergone CVVH for a number of days, ensuring good metabolic control, so that possible short term loss of clearance as a consequence of AV port reversal has no detrimental effects. Exclusion Criteria: pre-existing chronic renal insufficiency requiring dialysis chronic immunosuppression liver cirrhosis Child-Pugh C severe or shock-related hepatitis Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: AV port reversal<br>Patients undergoing citrate CVVH. | Other: AV port reversal<br>* Reversal of the AV port at 1h Reversal of the AV port to start position at 7h<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in citrate concentration in circuit after AV port reversal |  | 8 hours | 
| change in post-filter ionised Ca after AV port reversal |  | 8 hours | 
| change in clearance after AV port reversal |  | 8 hours |