Prevalence of Hypotension Associated With Preload Dependence During Continuous Renal Replacement Therapy

Study Overview
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Brief Summary
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Per-dialytic hypotension is common in Intensive Care Unit patients under continuous renal replacement therapy, and occurs in nearly 50% of the patients. To date, there is a lack of study having characterized the underlying mechanism of hypotension in this setting. New diagnostic methods are now available with high reliability to identify hypovolemia as the underlying cause of hypotension, among which change in cardiac index during passive leg raising may be the less affected by restrictive validity criteria. A change in cardiac index greater than 10% during this test is highly predictive of preload dependence, i.e the probability than cardiac index will increase if cardiac preload increases. The aim of this study is then to identify, among hypotensive episodes occurring during renal replacement therapy in Intensive Care Unit patients, the percentage of episodes related to preload dependence as identified by passive leg raising.

Official Title
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Prevalence of Hypotension Associated With Preload Dependence During Continuous Renal Replacement Therapy

Conditions
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Kidney Injury, Renal Failure, Acute

Intervention / Treatment
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* Other: Hemodynamic monitoring during passive leg raising


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Intensive Care Unit patients with acute kidney injury under continuous renal replacement therapy initiated since less than 24 hours under hemodynamic monitoring by the PiCCO® device. Exclusion Criteria: lower limb amputation inferior vena cava compression intracranial hypertension age below 18 year pregnancy advance directives to withhold or withdraw life sustaining treatment, lack of written informed consent by patient or next of kin lack of affiliation to social security as required by French regulation patient under a legal protective measure previous inclusion in current study inclusion in another research study

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with acute kidney injury<br>Intensive care unit patients with acute kidney injury. Patients under continuous renal replacement therapy and hemodynamic monitoring. | Other: Hemodynamic monitoring during passive leg raising<br>* Measurement of hypotensive episodes related to preload dependance.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Presence of hypotensive episode by hemodynamic monitoring | An hypotensive episode is defined as mean arterial pressure < 65 mm Hg and one of the following events : Fluid administration OR increase of vasopressor dose OR decrease of fluid removal | 7 days | 
| Preload dependence identified by cardiac index greater than 10% during passive leg raising | The passive leg raising allows to identify the percentage of hypotensive episodes related to preload dependence. A change in cardiac index greater than 10% during this test is highly predictive of preload dependence, i.e the probability than cardiac index will increase if cardiac preload increases. | 7 days |