Bioelectrical Impedance in Monitoring Hyperhydration and Polyneuromyopathy in Critically Ill Patients

Study Overview
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Brief Summary
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This prospective, blinded observational clinical study was aimed to determine the effect of hyperhydration and muscle loss measured by Bioelectrical impedance vector analysis (BIVA) on mortality. The aim was to compare hydratation parameters measured by BIVA: OHY, Extracellular Water (ECW) / Total Body Wate (TBW) and quadrant, vector length, phase angle (PA) with cumulative fluid balance (CFB) recording (input-output) in their ability in predicting mortality as the abilities of the prognostic markers PA (BIVA), Acute Physiology and Chronic Health Evaluation II (APACHE II - score) and presepsin (serum Cluster of Differentiation (CD) 14-ST). The investigators also compared BIVA nutritional indicators (SMM, fat) with BMI and laboratory parameters (albumin, prealbumin and C-reactive protein (CRP) inflammation parameters) in the prediction of mortality. An important goal was to evaluate the usability of the BIVA method in critically ill patients on extracorporeal circulation, to compare the impedance data of the extracorporeal membrane oxygenation (ECMO) and non-ECMO groups.

Detailed Description
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Hyperhydration has a detrimental effect on mortality risk and morbidity, increases the risk of acute kidney failure, the need of renal replacement therapy (RRT), worsens recovery of renal functions and worsens lung injury (ALI), infectious complications, and causes prolonged artificial pulmonary ventilation (APV), the length of stay on Intensive care unit (ICU), and impairs wound healing. Real-time assessment of fluid status and management of fluid administration in critically ill patients is challenging. Echocardiography can rapidly identify hemodynamic phenotypes, but it is rather intermittent than continuous methods and requires experienced and trained staff. Semi-invasive methods, based on stroke volume monitoring as the area under the arterial curve and variability of stroke volume variation (SVV) evaluate intravascular volume. However, these methods lack information about the interstitial fluid, part of extracellular water (ECW), or intracellular fluid water (ICW). This problem is partially solved by transpulmonary thermodilution with extravascular lung water (EVLW) measurement and lung ultrasound. Calculating the cumulative balance (CBF) is imprecise, especially in the area of fluid output for insensible losses or third-space fluid losses. Even more imprecise is the clinical assessment of peripheral edema and blood flow. And gold standard deuterium dilution methods for total body water (TBW) are not usable in daily practice in the ICU settings. In addition to hyperhydration, the rapid loss of muscle tissue in critically ill patients has a negative impact on the course of the disease. Polyneuromyopathy affects up to 40 % of critically ill patients, patients in a severe catabolic state with an activated systemic inflammatory response (SIRS), with corticosteroid therapy, and immobilized on long-term artificial lung ventilation are at risk. Monitoring lean body mass, especially skeletal muscle mass (SMM), is still difficult. Anthropometric measurements and ultrasound measurements of the quadriceps muscles are not ideal because they are time-consuming and require well-trained staff. Some laboratory parameters such as albumin are likely to be influenced by inflammation (CRP), and hydration. Dual-energy X-ray absorptiometers (DEXA) using two different wavelengths of low-intensity X-rays give a relatively accurate picture of bone mass and soft tissues (fat-free mass, active mass, fat). However, repeated X-ray examination in immobilized critically ill patients is not the method of choice. Bioelectrical impedance vector analysis (BIVA) is a simple, rapid, and noninvasive bedside technique, based on the principle that the flow of altering electrical current through a particular tissue differs depending on the content of water and electrolytes. It is thus able to measure body composition as skeletal muscle mass (SMM), and body cell mass (BCM), including total body water and extracellular water. And with the use of 50 frequencies of bioimpedance spectroscopy (BIS), it is possible to distinguish TBW, ECW, and from their different intracellular water, because only electric current with a frequency higher than 100 Hertz (Hz) passes through the cell membrane. However, the technique cannot distinguish between intravascular and interstitial volumes in the extracellular compartment. According to a number of studies, the results of bioimpedance parameters of body composition are comparable to DEXA. However, BIA overestimates the representation of muscle. An important parameter is the phase angle (PA), which detects a time delay of the passage of current through the cell membrane, i.e., a phase shift between the sinusoidal voltage and current waveforms. PA reflects BCM and serves as an important prognostic factor, with a normal value of 4-15°. Of the laboratory markers, presepsin (PSEP) has prognostic significance. Presepsin, soluble Cluster of differentiation 14 (sCD14), is a glycoprotein expressed in the membranes of monocytes and macrophages in response to pathogen-associated molecular patterns (PAMPs: lipopolysaccharide, peptidoglycan) part of the bacterial wall or to other damage to cells - damage-associated molecular patterns (DAMPs). An interesting finding is its prognostic role, i.e. higher values in non-surviving patients, evaluated by a number of studies.

Official Title
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Bioelectrical Impedance Vector Analysis (BIVA) in Monitoring Hyperhydration and Polyneuromyopathy in Critically Ill Patients

Conditions
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Respiratory Distress Syndrome, Acute, Respiratory Insufficiency, Lung Ventilator, Hyperhydration, Hypoxemia, Chronic Obstructive Pulmonary Disease Exacerbation, Septic Shock

Intervention / Treatment
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* Device: Bioelectrical impedance vector analysis (BIVA)
* Diagnostic Test: Blood and urine analysis
* Diagnostic Test: cumulative water balance


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with respiratory insufficiency, with the assumption of at least 7 days of artificial lung ventilation (medical, trauma, surgical patients) Primary acute respiratory distress syndrome (ARDS) (pulmonary involvement): pneumonia, inhalation trauma, chest trauma (lung contusion), aspiration Secondary ARDS (extrapulmonary): sepsis, shock states, acute pancreatitis, polytrauma, burns, non-cardiogenic shock, intoxication, TRALI (massive blood transfusion), drowning Patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) Exclusion Criteria: Patients with unfavorable prognosis APACHE II ≥30 Metastatic malignancy Conditions after cardiopulmonary resuscitation (KPCR) before admission Cerebral edema Brain trauma Intracranial hypertension Liver cirrhosis A pre-existing neurodegenerative disease Patients with pacemakers, defibrillators, pregnancy (conditions contraindications to use of bio-electrical impedance).

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 |
| --- | --- |
| Group of Patients who Survived (S)<br>The group is defined by the number of patients who survived. | Device: Bioelectrical impedance vector analysis (BIVA)<br>* BIVA is a simple, rapid, and noninvasive method, based on the principle that the flow of altering electrical current through a particular tissue differs depending on the content of water and electrolytes, used for monitoring hydratation and nutritional status in critically ill patients.<br>Diagnostic Test: Blood and urine analysis<br>* For regular measurement in 2-3 terms, depending on the length of hospitalization (the first measurement took place within 48 hours of admission, followed one week after admission and the last before transport from the ICU): laboratory indicators of nutritional status will also be taken (albumin, prealbumin, creatinine), inflammation (C-reactive protein, presepsin) and 25-hydroxyvitamin D level.<br>Diagnostic Test: cumulative water balance<br>* Cumulative balance is the sum of daily fluid balances during hospitalization.<br>|
| Group of Patients who Died (D)<br>The group is defined by the number of patients who died. | Device: Bioelectrical impedance vector analysis (BIVA)<br>* BIVA is a simple, rapid, and noninvasive method, based on the principle that the flow of altering electrical current through a particular tissue differs depending on the content of water and electrolytes, used for monitoring hydratation and nutritional status in critically ill patients.<br>Diagnostic Test: Blood and urine analysis<br>* For regular measurement in 2-3 terms, depending on the length of hospitalization (the first measurement took place within 48 hours of admission, followed one week after admission and the last before transport from the ICU): laboratory indicators of nutritional status will also be taken (albumin, prealbumin, creatinine), inflammation (C-reactive protein, presepsin) and 25-hydroxyvitamin D level.<br>Diagnostic Test: cumulative water balance<br>* Cumulative balance is the sum of daily fluid balances during hospitalization.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Body Mass (physique) - Bioelectrical impedance analysis (BIA) | Bioelectrical impedance analysis (BIA) comparison of skeletal muscle mass, body fat and body water (expressed in %) in patients hospitalized in the ICU. | The first within 48 hours of admission, the second one week after admission and third before transport from the ICU | 
| Body Mass (physique) - Phase Angle (PA) | Assessment of the Phase angle (expressed in degrees) as a part of BIA in patients hospitalized in the ICU. | The first within 48 hours of admission, the second one week after admission and third before transport from the ICU | 
| Body Mass (physique) - BIVA vector analysis (Cole Cole graf) | Assessment of the BIVA vector analysis (Cole Cole graf, expressed as a optimal curve dependence of resistance on reactance always at a specific frequency, divided into quadrants) in patients hospitalized in the ICU. | The first within 48 hours of admission, the second one week after admission and third before transport from the ICU | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Indicators of nutritional status (albumin, prealbumin) | Assesment of indicators of nutritional status (albumin, prealbumin in g/l) in serum of patients admitted to Intensive Care Unit (ICU). | The first within 48 hours of admission, the second one week after admission and third before transport from the ICU | 
| Indicator of inflammation (CRP) | Assesment of indicator of inflammation (C-reactive protein in mg/L) in serum of patients admitted to Intensive Care Unit (ICU). | The first within 48 hours of admission, the second one week after admission and third before transport from the ICU | 
| Indicator of inflammation - presepsin (PSEP) | Assesment of indicator of inflammation measurements (presepsin in ng/L) in serum of patients admitted to Intensive Care Unit (ICU). | The first within 48 hours of admission, the second one week after admission and third before transport from the ICU | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bioelectrical impedance, Hyperhydration, Critical care, Extracorporeal membrane oxygenation Mortality