A Longitudinal Investigation of Energy Expenditure and Substrate Utilization in Critically Ill Patients

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

COMPLETED

Total Enrollment

714 participants

Study Classification

OBSERVATIONAL

Study Start Date

2022-02-21

Study Completion Date

2025-03-21

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

The metabolic alterations associated with critical illness have significant implications for the nutritional management of ICU patients. Despite this, little is known about these changes in patients requiring prolonged organ support and nutritional therapy.

The overall aim of this study is to describe changes in metabolism over time in a large prospective cohort of patients requiring \>10 days of ICU care. Our hypothesis is that there is a significant change in mean energy expenditure and respiratory quotient (RQ) between the early (day 1-3), intermediate (day 4-10) and late (\>10 days) phase in ICU.

Related Clinical Trials

Explore similar clinical trials based on study characteristics and research focus.

Metabolic and Nutritional Characteristics of Long-stayer ICU Patients

NCT03938961

Critically Ill

COMPLETED

The Effect of a 6-month Dietitian-tailored Nutrition Intervention to Patients With Critical Illness (DETAIL)

NCT07149246

ICU Patients Nutrition Intake Critical Illness

RECRUITING NA

Observational Cohort Study on the Use of Parenteral Nutrition and Clinical Outcomes in Adult Critically Ill Patients

NCT04143503

Critical Illness

COMPLETED

Acylcarnitine Profile After Intensive Care

NCT05115734

Critical Care Carnitine Metabolism Disturbances

RECRUITING

Energy Expenditure in ICU Patients Using Predictive Formulas and Various Body Weights Versus Indirect Calorimetry

NCT02552446

Critical Illness Body Weights

COMPLETED

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Background

Critical illness has profound effects on human metabolism. The most prominent feature in the early phase is an upregulation of catabolic pathways, which promotes the production of endogenous energy substrates and net protein breakdown \[1\].

There is very little published data describing trends of energy expenditure and substrate utilization in patients with a prolonged ICU stay. While this group only constitutes a small fraction of ICU patients, it accounts for a large part of ICU resource allocation, morbidity and mortality \[2\]. Several studies have been conducted in recent years to better characterize patients with persistent critical illness, focusing on markers of catabolism and inflammation \[3, 4\]. It is not known if these changes are associated with alterations in energy metabolism and substrate utilization.

Bridging these knowledge gaps will improve our understanding of the nutritional needs and metabolism of patients beyond the early phase in ICU. We therefore plan to conduct a prospective observational multi-center study to address these questions.

Aim and hypothesis

The overall aim of this project is to describe longitudinal changes in energy expenditure and associated clinical characteristics in a large cohort of patients with a prolonged ICU stay. Our hypothesis is that there is a significant change in mean energy expenditure and respiratory quotient (RQ) between the early (day 1-3), intermediate (day 4-10) and late (\>10 days) phase in ICU. Correlations between metabolic rate and other clinical characteristics will also be analysed for hypothesis-generating purposes.

Population

All adult ICU patients with at least one measurement of energy expenditure by indirect calorimetry at participating study sites will be included in the study. Study sites are encouraged to routinely perform indirect calorimetry every 3-4 days. Study subjects will be followed until ICU discharge or death, whichever comes first.

Data collection and reporting

Patient data will be reported pseudonymized through a secure online form.

On admission

* Admission date
* Admission diagnosis (ICD-10)
* Surgery prior to admission (YES/NO), elective or emergent
* Outcome prediction score (SAPS 3, APACHE III/IV, MPM, etc.) and risk of death on admission (%)
* ICU source admission (ER/ward/OT/other ICU)
* Days in hospital before ICU admission

Demographic and anthropometric data:

* Sex (male/female)
* Age (years)
* Weight (kg)
* Height (cm)

Chronic comorbidities registered in electronic health records (YES/NO):

* Hypertension
* Ischemic heart disease
* Heart failure
* Diabetes mellitus
* COPD
* Chronic kidney disease
* End-stage renal disease
* Liver cirrhosis
* Active cancer (not in complete remission)
* Haematological malignancy
* Solid organ transplant

On the day of each indirect calorimetry

* REE (kcal/24 h), RQ, VO2 (ml/min), VCO2 (ml/min) and date of investigation
* Invasive mechanical ventilation (YES/NO) or renal replacement therapy (YES/NO)

If YES to invasive mechanical ventilation:

* Fraction of inspired oxygen
* Positive end-expiratory pressure (cmH2O)

Factors that may influence REE:

* Sequential organ failure assessment (SOFA) score
* Fever (≥38.5 ℃) within 2h of measurement (YES/NO/MISSING)
* Richmond Agitation-Sedation Scale score

Results of daily blood tests if available from routine testing:

* P-CRP (mg/L)
* P-albumin (g/L)
* P-urea (mmol/L)
* P-creatinine (μmol/L)
* Haemoglobin (g/L)

Medications, nutrition and other therapies:

* Infusions of vasoactive medications (YES/NO, if YES → name of medication(s))
* Infusions of sedatives or analgesics (YES/NO, if YES → name of medication(s), if propofol → infusion rate at time of measurement)
* Infusions of parenteral and/or enteral nutrition (YES/NO, if YES → brand name, formulation and rate at time of measurement)

On discharge

* Discharge date
* Survival status (ALIVE/DEAD)
* Sepsis during ICU stay (NO/SEPSIS/SEPTIC SHOCK)

Sample size considerations

The goal of this study is to include ≥200 patients with an ICU length of stay of \>10 days. Based on data from the Swedish Intensive Care Registry between 2015-2019, these patients accounted for 5% of all ICU admissions \[5\]. This proportion is comparable to results from a registry study conducted in Australia and New Zealand of over one million ICU admissions \[2\]. Based on these figures we intend to screen 6000 unique patients for study participation, accounting for the possibility that multiple measurements of indirect calorimetry are not consistently performed. In total we expect to include around 1250 unique subjects with at least one measurement with indirect calorimetry.

Statistics

Descriptive data will be presented as mean +/- standard deviation or median (interquartile range) as appropriate. The primary and secondary outcome measures will be analysed using a generalized linear mixed-effects model. Exploratory outcomes and their association to other clinical variables will be analysed using generalized linear regression models. If values are found to be not missing at random, conditional logistic regression censoring will be used to calculate inverse probability weights for accounting for difference in drop-out probabilities.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Critical Illness

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Observational Model Type

COHORT

Study Time Perspective

PROSPECTIVE

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Indirect calorimetry

Measurement of metabolic rate (kcal/day) by respiratory gas analysis.

Intervention Type DIAGNOSTIC_TEST

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

1. \>/= 18 years old.
2. Admitted to the ICU of a participating study site.
3. At least one measurement of energy expenditure performed during ICU stay.

Exclusion Criteria

1. Patients readmitted to the ICU of a participating study site \>72 hours after ICU discharge and already included in the study (≥1 measurement of energy expenditure performed during prior admission). If a patient is readmitted within ≤72 hours of ICU discharge this is considered a continuation of the last ICU admission for the purposes of this study.
2. Burns \>20% of body surface area.
3. Pregnancy.

Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No