Resting Energy Expenditure
Conditions
Keywords
lean body mass, resting energy expenditure, oxygen consumption, Indirect calorimetry, carbon dioxide excretion, respiratory quotient
Brief summary
The study aims to correlate Lean Body Mass (LBM) Evaluated by Musculoskeletal Ultrasound with Resting Energy Expenditure (REE) measured by Indirect Calorimetry and to generate a predictive equation of REE based on LBM, in addition to identifying other factors that may affect REE such as age, gender, and severity scores.
Detailed description
Caloric needs in critically-ill patients fluctuate significantly over the course of the disease which might expose patients to either malnutrition or overfeeding.Malnutrition is associated with deterioration of lean body mass (LBM), poor wound healing, increased risk of nosocomial infection, and weakened respiratory muscles. On the other hand overfeeding in medically compromised patients can promote lipogenesis, hyperglycemia, and exacerbation of respiratory failure. Many factors may affect the resting energy expenditure (REE) through manipulation of oxygen consumption (VO2). One of the strongest determinants of REE is the LBM. A measurement of muscle mass and changes in muscle mass could thus provide an index of LBM in critically ill patients. At present, computerized tomography, magnetic resonance imaging and dual-energy X-ray absorptiometry (DXA) are widely used as reference methods for evaluating LBM in vivo. However, these methods are impractical in critically ill patients. More practically, ultrasound scanning is a simple, portable, safe, and a low-patient burden technique. Several studies found that the use of ultrasound can be a good estimate to LBM. Indirect calorimetry remains the accepted standard for determining the REE in the critically ill. Indirect calorimetry measures oxygen consumption(VO2) and carbon dioxide excretion (VCO2 ) (both in mL/min), which are used to calculate the respiratory quotient and the resting energy expenditure. Although, the measured LBM has been shown as an important determinant of REE, there was no previous study tested the relationship between estimated LBM by ultrasound-based muscle thickness measurement and REE.
Interventions
DIAGNOSTIC_TESTUS Muscle layer thickness (MLT) estimation
Three measurements will be made at each of three sites; mid-upper arm, forearm and thigh anteriorly and the mean value will be calculated. Measurement sites will be marked with indelible ink to ensure day-to-day consistency. 1. Thigh: MLT of the quadriceps femoris muscle (M. Vastus intermedius and M. rectus femoris) will be assessed bilaterally 2. Mid-upper arm: Muscle layer thickness will be measured over the biceps,midway between the tip of the acromion and the tip of the olecranon 3. Forearm: A point midway between the antecubital skin crease and the ulnar styloid was marked and muscle thickness down to the interosseus membrane
DIAGNOSTIC_TESTREE estimation by indirect calorimetry
REE will be calculated using indirect calorimetry via metabolic module on General Electric ventilator (Engstrom Carestation and Carescape R860, GE Health care, USA) All indirect calorimetric measurements will be done using standardized technique. Gas calibration will be performed before each measurement, and the measurements will last for at least 30 minutes. Measurements will be taken with the patient lying supine and ventilator settings left unchanged for at least 60 minutes ahead of indirect calorimetry. The REE will be calculated during the first 24 hours of admission to ICU.
Sponsors
Eslam Ayman Mohamed Shawki
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
\- Patient requiring ventilatory support \> 24 hours
Exclusion criteria
* Patient who will require FIO2 more than 0.6. * Air leak from the chest tube. * Patient with body temperature \> 39oC. * Patients with known endocrine dysfunction. * Patients on parenteral nutrition
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| correlation between LBM derived from ultrasound MLT and REE by indirect calorimetry | 24 hours of ICU admission | The correlation of the LBM derived from ultrasound MLT to the REE measured within 24 hours of ICU admission with indirect calorimetry |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Predictive equation for REE based on US measurement of MLT | 24 hours of ICU admission | generation of predictive equation of REE based on ultrasound measurement of MLT |
| Estimation of the effect of severity scores on the REE | 24 hours of ICU admission | Estimation of the effect of severity scores on the REE |
Countries
Egypt
Outcome results
None listed