What is the purpose of the ICG Simulator – why should I purchase one?

Lifegard II ICG Derived Parameters:

INDENStroke Volume / Stroke Index (SV / SI): [30-120] / [30-65] ml /  ml/m²

INDENCardiac Output / Cardiac Index (CO / CI): [3.0 – 10.0] / [2.8 – 4.2]      l/min  /  l/min/m²

INDENSystemic Vascular Resistance / SVR Index (SVR / SVRI): [770 – 1560] /
INDEN[1340- 2480] dyn *s/cm5   / dyn * s * m2/cm5

INDENVelocity Index (VI) and Acceleration Index (ACI): [33 – 75] 1/1000s / [60 – 150] 1/100 s²

INDENThoracic Fluid Content (TFC): [21 – 50] 1/kOhm

INDENPre-Ejection Period (PEP): [40 – 100] ms

INDENLeft Ventricular Ejection Time (LVET): [200 – 350] ms

INDENEjection Time Ratio (ETR): [20 – 40] %

INDENSystolic Time Ratio (STR): [15 – 45] %

INDENLeft Cardiac Work Index (LCWI): [3.3 – 5.3] kg m/m²

Which CO₂ starter kit is best for you?

What is the purpose of the ICG Simulator – why should I purchase one?

For the LIFEGARD II series of patient monitors equipped to monitor ICG, the Analogic AN4700-AC001 ICG simulator is the perfect diagnostic tool for the facility’s lab, right along side the more familiar BP, ECG and temperature simulators. Although it is not to be used for calibration (the ICG function of the monitor does not require calibration), the technician can determine quickly if a problem is in the monitor or cables, or is an operator error.

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Lifegard ICG Derived Parameters:

The Lifegard ICG Monitor offers noninvasive, continuous, beat-by-beat measurements of:

• Stroke Volume (SV)                                                    [30-120] ml
• Stroke Index (SI)                                                         [30-65] ml/m²
• Cardiac Output (CO)                                                    [3.0 – 10.0] l/min
• Cardiac Index  (CI)                                                      [2.8 – 4.2] l/min/m²  
• Systemic Vascular Resistance (SVR)                           [770 – 1560] dyn * s/cm⁵
• SVR Index (SVRI)                                                       [1340- 2480] dyn * s * m²/cm⁵
• Acceleration Index (ACI)                                              [60 – 150] 1/100 s²
• Velocity Index (VI)                                                       [33 – 75] 1/1000s
• Ejection Velocity Index (EVI)                                       [1.2 – 2.8] W/s
• Pre-Ejection Period (PEP)                                            [40 – 100] ms
• Left Ventricular Ejection Time (LVET)                            [200 – 350] ms
• Ejection Time Ratio (ETR)                                           [20 – 40] %
• Systolic Time Ratio (STR)                                            [15 – 45] %
• Thoracic Fluid Content (TFC)                                       [21 – 50] 1/kW
• Left Cardiac Work Index (LCWI)                                 [3.3 – 5.3] kg m/m²

Stroke Volume / Stroke Index (SV / SI): [30-120] / [30-65] ml /  ml/m²

SV is the amount of blood the left ventricle ejects in one beat, measured in milliliters per beat (ml/beat). SV can be indexed to a patient's body size by dividing by Body Surface Area (BSA) to yield Stroke Index (SI).

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Cardiac Output / Cardiac Index (CO / CI): [3.0 – 10.0] / [2.8 – 4.2]      l/min  /  l/min/m²

CO is the amount of blood the left ventricle ejects into the systemic circulation in one minute, measured in liters per minute (l/min). CO is Stroke Volume (SV) multiplied by Heart Rate (HR). CO can be indexed to a patient's body size by dividing by Body Surface Area (BSA) to yield Cardiac Index (CI).

CO = SV x HR

CI= CO/BSA

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Systemic Vascular Resistance / SVR Index (SVR / SVRI): [770 – 1560] / [1340- 2480] dyn * s/cm5   / dyn * s * m2/cm5  

SVR is representative of the force that the left heart must pump against in order to deliver the stroke volume into the periphery. SVR is directly proportional to blood pressure and indirectly proportional to blood flow (CO). SVR is a measure of afterload.

SVR is determined by the following equation:

SVR = [(MAP - CVP) / CO] x 80

SVR can be indexed to a patient's body size by substituting Cardiac Index for Cardiac Output to yield Systemic Vascular Resistance Index (SVRI).

SVRI = [(MAP - CVP) / CI] x 80

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Velocity Index (VI) and Acceleration Index (ACI): [33 – 75] 1/1000s / [60 – 150] 1/100 s²

VI is the maximum rate of impedance change, and is representative of aortic blood velocity. ACI is an index of the peak acceleration of aortic blood flow.  ACI= dZ²/dt²MAX /TFI and is representative of aortic blood acceleration. Together the indices are believed to reflect cardiac contractility, or the pumping force of the heart.

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Thoracic Fluid Content (TFC): [21 – 50] 1/kOhm

TFC is representative of total fluid volume in the chest, comprised of both intra-vascular and extra-vascular fluid. TFC is calculated as the inverse of the baseline impedance measurement. Baseline impedance is directly proportional to the amount of conductive material (i.e., blood, lung water) in the chest.

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Pre-Ejection Period (PEP): [40 – 100] ms

PRE-EJECTION PERIOD (PEP) [msec] is the interval between R wave peak and B point of the ICG.  It is the period of isovolumic ventricular contraction.

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Left Ventricular Ejection Time (LVET): [200 – 350] ms

The B point marks the opening and the X point the closing of the aortic valve.  The LVET is the duration of the mechanical systole.

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Ejection Time Ratio (ETR): [20 – 40] %

The part of the mechanical systole from the whole heart cycle. (HPD = duration of the heart period.)

 ETR = 100% * LVET / HPD

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Systolic Time Ratio (STR): [15 – 45] %

SYSTOLIC Time ratio (STR): Calculated by the systolic time intervals (STI) of pre-ejection period (PEP) and left ventricular ejection time (LVET).  [STR= 100% PEP/LVET].

STR = 100% x PEP / LVET

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Left Cardiac Work Index (LCWI): [3.3 – 5.3] kg m/m²

LCWI parallels myocardial oxygen consumption, and is the product of blood pressure and blood flow. LCWI is determined with the following equation:

LCWI = (MAP - PAOP) x CO x 0.0144 / BSA

PAOP is Pulmonary Artery Occluded Pressure, or wedge pressure. Outside of direct measurement with a Pulmonary Artery Catheter, a default value of 7 mm Hg can be used because of PAOP's minimal effect on LCW determination.

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Which CO₂ starter kit is best for you?

 For LIFEGARD II monitors Models AN4321P and AN4323P equipped to measure CO₂, Analogic offers two different starter kits.

 CCU Starter Kit, Model number 10-63902-01, is designed for use with patients on ventilation such as in the ICU. CO₂ monitoring can be performed with diminished risk of hypoventilation, ventilatory depression, airway obstruction, or compromise.

Procedural Sedation Starter Kit, Model number 10-63901-01, is designed for use with minor surgical procedures such as endoscopy. CO₂ readings are delivered from a specialized cannula that fits into the Microstream^Ò Smart BiteBlocÔ.

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