A Net Ultrafiltration Challenge to Predict Preload-dependence (UF CHALLENGE)

Civil Hospices of Lyon

Status: Completed

Conditions: Acute Kidney Injury

Treatments: Diagnostic Test: Slow ultrafiltration challenge; Diagnostic Test: Fast ultrafiltration challenge

Study type: Interventional

Funder types: Other

Identifiers

NCT05214729

69HCL21_1250

2021-A02939-32 (Other Identifier)

Details and patient eligibility

About

Hemodynamic instability episodes are a frequent complication of renal replacement therapies in critically ill patients, and their incidence is associated with worse survival. Hypovolemia, identified by the existence of biventricular preload dependence, is responsible for one episode out of two, and may justify a decrease in or cessation of fluid removal by net ultrafiltration (UF). To date, preload dependence is most frequently identified by evaluating the effects on cardiac output of postural changes (passive leg raising), impact of cardio-pulmonary interactions in ventilated patients, or fluid challenge. However, none of these tests may help identify a patient whose cardiac output is at risk of becoming preload dependent, that is situated at the inflexion point of the Frank Starling curve.

Our study aims to evaluate the effects on cardiac output (measured by a transpulmonary thermodilution technique) of 2 net ultrafiltration challenges, consisting fast removal of 250 ml of ultrafiltrate over 15 and 30 minutes respectively, and compare their diagnostic performance to the reference technique of preload dependence assessed by postural changes (passive leg raising) performed after the UF challenge.

Enrolled participants will undergo both UF challenges, following a randomized crossover design, in which the order of UF challenge duration (15 or 30 minutes) is randomized, separated by a washout period of 24 hours.

Enrollment: 20 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• adult patient, aged 18 year or older
• under mechanical ventilation and continuous general anesthesia, with a positive end-expiratory pressure of 5 cmH2O or more
• with stage 3 KDIGO acute kidney injury
• treated with continuous renal replacement therapy for less than 14 days
• ongoing continuous cardiac output monitoring
• with a predicted intensive care length of stay of 24 hours or more at time of screening

Exclusion criteria

• High arterial lactate concentration, > 4.0 mmol/L at time of screening
• Calibrated cardiac index < 2.0 L/min/m2 or > 4.0 L/min/m2 at time of screening
• Positive postural change maneuver in the last 2 hours preceding screening
• Patient under extracorporeal membrane oxygenation
• Patient with active bleeding requiring emergent transfusion
• Patient under chronic maintenance dialysis or renal transplant recipient
• Acute ischemic or hemorrhagic stroke complicated with coma and requiring mechanical ventilation
• Fulminant hepatitis (acute liver injury, hepatic encephalopathy, icterus and a drop in prothrombin < 50% in less that 15 days
• Impossible postural change maneuver
• Pregnant or lactating patient
• Imminent death
• Patient under legal protection measures as by French regulation
• Patient already enrolled in the present study
• Patient already participates in a study with protocolized net ultrafiltration, ongoing at time of screening

Trial design

Primary purpose: Diagnostic

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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20 participants in 2 patient groups

Fast to Slow Group

Experimental group

Description:

The Fast to Slow Group corresponds to enrolled patients randomized, following the sequential crossover design, to first perform the fast UF challenge immediately after inclusion, followed by the slow UF challenge after a washout period of 24 hours.

Treatment:

Diagnostic Test: Fast ultrafiltration challenge

Diagnostic Test: Slow ultrafiltration challenge

Slow to Fast Group

Experimental group

Description:

The Slow to Fast Group corresponds to enrolled patients randomized, following the sequential crossover design, to first perform the slow UF challenge immediately after inclusion, followed by the fast UF challenge after a washout period of 24 hours.

Treatment:

Diagnostic Test: Fast ultrafiltration challenge

Diagnostic Test: Slow ultrafiltration challenge