Cardiac Output Measurement With NICCOMO and PiCCO Devices at Different PEEP Levels

Study Overview
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Brief Summary
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Thermodilution cardiac output measurement is a reliable method, but it is an invasive one. PiCCO device requires cannulation of central vein and peripheral artery. Impedance method requires only attachment of special electrodes. Non-invasive methods are less accurate. Aim of study is to assess accuracy and reliability of impedance method ( using NICCOMO device) in comparison of thermodilution method ( using PiCCO device) at different PEEP levels.

Detailed Description
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Echocardiography is performed prior to measurement to exclude patients with heart valve abnormalities. Patients without spontaneous ventilation ( deeply unconscious, sedated or sedated and paralysed), ventilated with controlled mechanical ventilation mode with tidal volume 6-8 ml/ideal body weight, resulting in EtCO2 35-45 mmHg, with PiCCO catheters implemented have additionally NICCOMO device attached. Fraction of inspired oxygen (FiO2) is set to achieve saturation >96% at positive end expiratory pressure (PEEP) 0 cmH2O. Measurement of cardiac output are performed on expiration at PEEP 0, 5, 10, 15 20 cmH2O and at optimal PEEP (obtained from P-V curve). Simultaneously CO value from impedance device is noted. Other haemodynamic parameters, calculated by both devices are also noted - stroke volume (SV), stroke volume variation (SVV), Cardiac index (CI), systemic vascular resistance (SVR), systemic vascular resistance index (SVRI).

Official Title
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Assessment of Reliability of Cardiac Output Measurement Based on Impedance (NICCOMO) - Method of Noninvasive Cardiac Output Measurement, Compared to Transthoracic Thermodilution (PiCCO) at Different PEEP Levels

Conditions
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Cardiovascular Diagnostic Techniques

Intervention / Treatment
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* Device: PICCO
* Device: NICCOMO


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: critically ill patients patients on mechanical ventilation circulatory insufficiency (present or in the past) monitored with with PiCCO device Exclusion Criteria: morbid obesity, short neck, severe pneumonia, inability to NICCOMO electrodes attachment, massive tissue oedema, non-sinus cardiac rhythm, tachycardia, low cardiac output, septic shock, heart valve pathologies, severe atherosclerosis, aortic prosthesis, severe hypertension, extremes of height and weight, intraaortic pump

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 |
| --- | --- |
| haemodynamics measuring<br>those with already implemented PICCO device get impedance device (NICCOMO) attached | Device: PICCO<br>* measurements based on thermodilution<br>Device: NICCOMO<br>* measurements based on impedance<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Numbers of measurements of haemodynamic parameters (CO, CI, SV, SVV, CI, SVR, SVRI) obtained with impedance, that differ from those obtained with thermodilution | measurements taken with impedance and thermodilution simultaneously, at PEEP 0, 5, 10, 15, 20 and at optimal PEEP | up to 90 minutes |