Influence of Renal Replacement TherApy on Indirect Calorimetry

Study Overview
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Brief Summary
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Renal replacement therapy may affect carbon dioxide elimination, which may theoretically influence measurement of energy expenditure by means of indirect calorimetry. However, available clinical studies are noct conclusive on this issue. This observational study aims to investigate the effect of renal replacement therapy on indirect calorimetry in critically ill mechanically ventilated patients.

Detailed Description
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Optimal Nutrition of the critically ill is still a clinical challenge. Current guidelines recommend that measurement of energy expenditure using indirect calorimetry should be favoured in critically ill patients. The technique is based on measurement of oxygen consumption and carbon dioxide elimination. Experimental studies have reported on carbon dioxide elimination via renal replacement therapy. Since acute kidney injury with requirement for renal replacement therapy (RRT) is common in the intensive care unit, the significance of carbon dioxide elimination via the dialyser should be clarified. However, available evidence from clinical studies is contradictory, one reason being the heterogenous study design. In this prospective observational study on critically ill mechanically ventilated medical patients requiring RRT, indirect calorimetry (IC) will be conducted twice on the same day with and without RRT: either immediately before commencement of RRT followed by a second IC with RRT after an RRT run time of an hour, or immediately before the end of an RRT session followed by a second IC an hour after the termination of RRT.

Official Title
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Influence of Renal Replacement TherApy on Indirect Calorimetry: a Prospective Observational Study

Conditions
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Acute Renal Failure, Mechanical Ventilation

Intervention / Treatment
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* Device: indirect calorimetry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: simultaneous requirement for mechanical ventilation and renal replacement therapy informed consent Exclusion Criteria: age <18 years requirement for therapeutic hypothermia serum lactate >4 mmol/l requirement for inspiratory oxygen fraction >0.6 and positive end-expiratory pressure >12 mbar leak in the ventilator circuit (e.g. due to a chest tube) requirement for extracorporeal circulatory support refusal to participate in the 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

| Intervention/Treatment |
| --- |
|Device: indirect calorimetry|indirect calorimetry with and without renal replacement therapy|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| energy expenditure | energy expenditure in kcal/d | 60 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Carbon dioxide elimination | Carbon dioxide elimination in ml/min | 60 minutes | 
| respiratory quotient | respiratory Quotient, defined as the Ratio of Carbon dioxide elimination to Oxygen consumption | 60 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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indirect calorimetry, energy expenditure, carbon dioxide elimination, renal replacement therapy, respiratory quotient