PiCCOplus PC8100 Operators Manual and Product Information Ver 7.1

About this Manual

About this Manual WARNING Read the Operating Instructions carefully before using the PiCCO plus equipment!

WARNING Important items of information, i.e. activities where operating personnel must proceed with extreme caution in order to avoid injury to themselves or the patient. These items of information are always shown in bold print.

CAUTION Items of information for which careful attention must be paid in order to avoid damage to the equipment or the software. These items of information are always shown in bold print. MEDICAL ELECTRICAL EQUIPMENT WITH RESPECT TO ELECTRIC SHOCK, FIRE, MECHANICAL AND OTHER SPECIFIED HAZARDS ONLY IN ACCORDANCE WITH UL 2601-1 and CAN/CSA C22.2 NO. 601-1 62DA

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Operator’s Manual PiCCO plus Version 7.1

Table of Content

Table of Content About this Manual...II Table of Content...III List of Figures ... VII 1.

Quick Reference Guide...1-1

2.

General Information ...2-1 2.1

Intended Use ... 2-1

2.2

Indications ... 2-1

2.3

Contraindications... 2-1

2.4

Warnings ... 2-2

2.5

Cautions ... 2-3

3.

Introduction ...3-1

4.

Intermittent Thermodilution Measurement ...4-1

5.

4.1

Principles of Cardiac Output Determination... 4-1

4.2

Principles of Volume Calculation ... 4-1

4.3

Parameter Obtained by Transpulmonary Thermodilution ... 4-2 4.3.1

Cardiac Output Transpulmonary ...4-3

4.3.2

Global End-Diastolic Volume (GEDV) and Intrathoracic Blood Volume (ITBV)...4-3

4.3.3

Extravascular Lung Water (EVLW) ...4-7

4.3.4

Pulmonary Vascular Permeability Index (PVPI) ...4-9

4.3.5

Cardiac Function Index (CFI) and Global Ejection Fraction (GEF)...4-9

4.3.6

Intracardiac R-L Shunt-Detection and Quantification ...4-10

Pulse Contour Analysis...5-1 5.1

Principles of Measurement ... 5-1

5.2

Calibration of the Pulse Contour Analysis ... 5-3

5.3

Parameter Obtained by Pulse Contour Analysis ... 5-3 5.3.1

Pulse Contour Cardiac Output (PCCO)...5-4

5.3.2

Arterial Blood Pressure (AP) ...5-4

5.3.3

Stroke Volume Variation (SVV) and Pulse Pressure Variation (PPV) ...5-4

5.3.4

Systemic Vascular Resistance (SVR) ...5-5

5.3.5

Index of Left Ventricular Contractility (dPmx) ...5-5

5.3.6

Integrating approach of hemodynamic instability ...5-6

6.

Ranges of Normal Values...6-1

7.

Bibliography ...7-1

Operation Manual PiCCO plus Version 7.1

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Table of Content

8.

System Description... 8-1 8.1

8.2

8.3

8.4

9.

General Information...8-3 8.1.1

Intended Use ... 8-3

8.1.2

Indications ... 8-3

8.1.3

Contraindications... 8-3

8.1.4

Warnings ... 8-4

8.1.5

Cautions ... 8-5

Unpacking and Inspection ...8-6 8.2.1

Unpacking... 8-6

8.2.2

Inspection ... 8-6

Starting Up...8-7 8.3.1

Key points... 8-7

8.3.2

Details ... 8-8

Menu Description...8-10 8.4.1

Input Menu... 8-12

8.4.2

Pressure Zeroing Menu ... 8-13

8.4.3

Configuration Menu ... 8-14

8.4.4

Main Menu... 8-15

8.4.5

Thermodilution Display Page... 8-16

8.4.6

Pulse Contour Display Page... 8-19

8.4.7

Info Screen ... 8-20

8.4.8

Thermodilution Info Screen ... 8-21

8.5

Printer ...8-22

8.6

Contrast Control ...8-22

8.7

Signal Indicator / Warning Indicator ...8-23

8.8

Battery Function ...8-23

8.9

Troubleshooting...8-24 8.9.1

Error Messages ... 8-24

8.9.2

Signal Transfer ... 8-26

8.10

Cleaning and Disinfecting the Device ...8-27

8.11

Maintenance and Service ...8-28

8.12

Transmission of AP Signal to Bedside Monitor...8-29

8.13

Data Transmission with RS232 Interface...8-31

Disposables ... 9-1 9.1

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PULSIOCATH Arterial Thermodilution Catheters ...9-1 Operator’s Manual PiCCO plus Version 7.1

Table of Content

9.2

PCCO Monitoring Kits ... 9-2

9.3

Injectate Temperature Sensor Housing... 9-2

9.4

PiCCO Kits ... 9-2

9.5

Disposable Accessories ... 9-2

10.

Accessories...10-1

11.

Specifications...11-1

12.

EMI Requirements...12-1

13.

Appendix...13-1 13.1

Equations for Calculated Values ... 13-1 13.1.1

Body Surface Area and Predicted Body Weight...13-1

13.1.2

Thermodilution Display Page ...13-1

13.1.3

Pulse Contour Display Page ...13-4

13.2

International Symbols... 13-6

13.3

Warranty... 13-7

13.4

Glossary ... 13-8

Operation Manual PiCCO plus Version 7.1

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Operator’s Manual PiCCO plus Version 7.1

List of Figures

List of Figures Figure 1: Schematic description of an indicator dilution curve and the time characteristics of interest...4-1 Figure 2: Indicator mixing chambers within the cardiopulmonary system (schematic) ...4-2 Figure 3: Structural regression analysis of the relation between Intrathoracic Blood Volume (ITBV) and Global End-Diastolic Volume (GEDV) ...4-4 Figure 4: Relationship between volume loading-induced changes in GEDVI and changes in SVI. ...4-5 Figure 5: Relationship between A, initial central venous pressure (CVP) and Stroke Volum Index (SVI); B, changes in central venous pressure and SVI in response to saline...4-6 Figure 6: Relationship between A, initial pulmonary artery occlusion pressure (PWP=PCWP) and SVI; and B, changes in PCWP and SVI in response to saline ...4-6 Figure 7: Patient management by combined use of EVLW and ITBV or GEDV ...4-8 Figure 8: R-L Shunt...4-10 Figure 9: Thermodilution curves ...4-10 Figure 10: Characteristic compliance during the heart phases ...5-1 Figure 11: Determination of the individual aortic compliance...5-2 Figure 12: Calculation of Pulse Contour Cardiac Output (PCCO)...5-2 Figure 13: Pathophysiological mechanisms of acute circulatory failure and PiCCO plus parameters ...5-6 Figure 14: Front panel of the PiCCO plus...8-1 Figure 15: Rear panel of the PiCCO plus ...8-2 Figure 16: Set up of PiCCO plus...8-7 Figure 17: Flowchart of PiCCO plus Software ...8-11 Figure 18: Printer ...8-22 Figure 19: Connection of rear panel for pressure transfer to bedside monitor...8-29

Operation Manual PiCCO plus Version 7.1

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List of Figures - Blank page -

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Operator’s Manual PiCCO plus Version 7.1

Quick Reference Guide

1.

Quick Reference Guide PiCCO plus QUICK REFERENCE GUIDE PURPOSE 1. Transpulmonary thermodilution: Cardiac output (CO), cardiac preload (GEDV, ITBV), extravascular lung water (EVLW), pulmonary vascular permeability (PVPI) and contractility: Global ejection fraction (GEF) and cardiac function index (CFI). 2. Continuous monitoring after initial calibration of arterial pulse contour with transpulmonary thermodilution: Pulse contour cardiac output (PCCO), heart rate (HR), stroke volume (SV), volume responsiveness (SVV, PPV), arterial pressure (AP), systemic vascular resistance (SVR), and index of left ventricular contractility (dPmx). 3. PiCCOplusV7.0 corrects for possible R-L shunting. CO, GEDV and EVLW are accurately measured in presence of severe right-to-left shunts and the shunt fraction is calculated automatically STARTING UP Knowledge of the operator’s manual is mandatory! 1. For the bolus injection please prepares the appropriate injectate (e.g. saline solution 0.9%). If the ELWI is above 10ml/kg, use a cold (<8°C) bolus injectate. 2. Insert a central venous catheter (CVC) 3. Insert a PULSIOCATH thermodilution catheter (e.g. PV2015L20, PV2014L08) into a larger artery (e.g. femoral or axillary artery) 4. Connect the potential equalization stud of the PiCCOplus to a secondary ground source separate from the primary grounding source 5. Connect the hospital grade mains power cable 6. Connect the injectate temperature sensor housing (PV4046) to the distal lumen of the CVC 7. Connect “interface cable” and the “Injectate temperature sensor cable“ to the PiCCOplus and to the “Injectate temperature sensor housing” 8. Connect the prepared PULSION monitoring kit (e.g. PV8115) to the PULSIOCATH thermodilution catheter 9. Connect the “arterial pressure cable” to the PiCCOplus and the monitoring kit, connect the “interface cable” to the thermodilution catheter 10. Switch on the PiCCOplus 11. Enter all necessary information into the Input menu 12. Perform a “zero adjustment” of the pressure signal THERMODILUTION MEASUREMENT 1. Change to the “Thermodilution display page” 2. Press “Start measurement-key” 3. Wait until the blood temperature status “STABLE“ is displayed 4. Inject the bolus as quickly and smoothly as possible. 5. Leave the stopcock turned off to the CVP monitoring until “COMPLETE” is displayed 6. Perform 3 TD measurements initially 7. Press INFO to recall or delete last measurements

PULSE CONTOUR MONITORING 1. 2. 3. 4.

Change to the “Pulse contour display page” Change to “Thermodilution display page” if recalibration is required Change between indexed or absolute values, if required Press INFO for Trend or Profile screens

RANGES OF NORMAL VALUES Values based on clinical experience (without guarantee!) Normal ranges

Unit

CI

3.0 - 5.0

l/min/m2

SVI

40 - 60

ml/m2

GEDI

680 - 800

ml/m2

ITBI

850 - 1000

ml/m2

ELWI

3.0 – 7.0

ml/kg

Pressure zeroing menu

PVPI

1.0 – 3.0

-

Zero key

SVV

≤ 10

%

Pulse contour display page

PPV

≤ 10

%

Thermodilution display page

GEF

25 – 35

%

CFI

4.5 - 6.5

1/min

MAP

70 – 90

mmHg

SVRI

1700 - 2400

dyn—s—cm-5—m2

SYMBOLS Input menu Configuration menu

Start measurement key Stop measurement key Info screen, sub selection Delete measurement Trend display page

ERROR MESSAGES

Profile display Indexed values (based on body surface

***

Not plausible / not available

area resp. body weight)

+++

Value above specification range

Absolute values

----

Value below specification range

Decrease values

See operator’s manual for detailed explanation of displayed error messages (E=ERROR)

Increase values Previous position Next position Exit key PARAMETER Thermodilution determinations: CO Cardiac output1) GEDV Global End-Diastolic Volume1 ITBV Intrathoracic Blood Volume1 EVLW Extravascular Lung Water1 PVPI Pulmonary Vascular Permeability Index GEF Global Ejection Fraction CFI Cardiac Function Index R-L Right-Left-Shunt Pulse contour analysis: PCCO Pulse Contour Cardiac Output1 HR Heart Rate SV Stroke Volume1 SVV Stroke Volume Variation PPV Pulse Pressure Variation APsys Systolic Arterial Pressure APdia Diastolic Arterial Pressure MAP Mean Arterial Pressure dPmx Index of Left Ventricular Contractility SVR Systemic Vascular Resistance1 1) Parameters can also be displayed as indexed values

E

Interpretation

0 S 1

Technically good measurement R-L Shunt Error in determination of Tinj.

2

Injection error

3

Inject faster than 10s

4-6

Error in calculation of thermodilution curve parameters

7

Time out (Thermodilution curve longer than 90s)

8

Blood temperature lower than injectate temperature

9

Invalid PCCO calibration

WARNING For safety of operation and for accuracy of measurements, only disposables and accessories approved by PULSION Medical Systems may be used with the PiCCO plus. Related patents: EP0947941, US6315735, JP3397716, US6200301, EP0637932, US5526817, JP3242655, EP1034737, US6491640, JP3375590, US6394961, EP1139867, US6537230, US6264613, P200010262, EP0666056, US5769082, JP3234462 Further patents pending

Joseph-Wild-Str. 20 • D-81829 Munich, Germany Phone +49-(0)89-459914-0 • Fax +49-(0)89-459914-18 E-mail: [email protected] • web: www.PULSION.com

Version 7.1

Operation Manual PiCCO plus Version 7.1

Quick Reference Guide

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Quick Reference Guide - Blank page -

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Operator’s Manual PiCCO plus Version 7.1

General Information

2.

General Information

2.1

Intended Use The PULSION PiCCO plus intended use is the determination and monitoring of cardiopulmonary and circulatory variables. Cardiac output is determined both continuously through arterial pulse contour analysis and intermittently through transpulmonary thermodilution technique. In addition, the PiCCO plus measures heart rate, systolic, diastolic and derived mean arterial pressure. Analysis of the thermodilution curve in terms of mean transit time (MTt) and downslope time (DSt) is used for determination of intra- and extravascular fluid volumes. If a patient’s weight and height are entered the PiCCO plus presents the derived parameters indexed to body surface area (BSA) and their body weight (BW) respectively.

2.2

Indications The PULSION PiCCO plus is indicated in patients where cardiovascular and circulatory volume status monitoring is necessary. This includes patients in surgical, medical, cardiac, burns and other specialty units where cardiovascular monitoring is desired, and patients undergoing surgical interventions of such magnitude that cardiovascular monitoring is necessary.

2.3

Contraindications Due to the invasiveness of the measurement, the PiCCO plus should not be used in patients where the placement of an indwelling arterial catheter is contraindicated. The PiCCO plus should only be used in patients where the expected results are reasonable in comparison to the risks. Patients on intra-aortic balloon counter pulsation (IABP) cannot be monitored with the pulse contour analysis of the device however the intermittent PiCCO thermodilution will give valid results even with IABP support.

Operation Manual PiCCO plus Version 7.1

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General Information

2.4

Warnings Federal law restricts this device for sale by or on the order of a physician. This device is intended for use in health care facilities by trained health care professionals. This device provides monitoring of physiological parameters. The clinical significance of changes in monitored parameters should be determined by a physician. For safety of operation and for accuracy of measurements, only disposables and accessories approved by PULSION Medical Systems AG may be used with the PiCCO plus. Explosion hazard when used in the presence of flammable anesthetics. Failure on the part of the responsible individual hospital or institution employing the use of the PiCCO plus to follow the service instruction may cause undue equipment failure and possible health hazards. When placing the arterial catheter into a large artery (i.e. femoral, brachial or axillary arteries) do not advance the tip of the catheter into the aorta. An intracardiac blood pressure measurement is not allowed. This means that the measuring position (i.e.catheter tip) should not be in the heart. When high frequency devices are used during surgery, the standard for high frequency devices for surgery IEC/TR3 61289-1 has to be followed. The patient is protected against electrical burns by enhanced isolations between the patient and the PiCCO plus, and by placement of the pressure transducer away from the body. All disposables must be discarded after use. Reuse of the disposables is strictly forbidden. Resterilisation may cause infections in the patient. Do not reconnect to an electrical power source if liquid has entered the PiCCO plus. Short circuit may damage the device and cause hazardous conditions for patient and user. Removal of the potential equalization stud from the rear of the PiCCO plus voids the IEC approval. Do not use a 3 wire to 2 wire adapter for the PiCCO plus. Do not touch the patient, bed or device during defibrillation. Do not allow conductive parts of the disposables to be in contact with any conducting parts of the device. The device is equipped with sealed lead battery cells. Do not charge the device in a gas tight container.

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Operator’s Manual PiCCO plus Version 7.1

General Information

2.5

Cautions Inspect the PiCCO plus thoroughly for damage. If the PiCCO plus appears to be damaged, contact PULSION Medical Systems. Do not use the PiCCO plus if the device appears to be damaged. Product damage may occur unless proper care is exercised during unpacking and installation. The user must verify the safety and proper state of the device before use. If the system check detects a failure, no function will be available and “SERVICE” is displayed on the screen. Turn the PiCCO plus off and contact your local PULSION representative for a service. Do not attempt to use or repair the PiCCO plus. If zero adjustment is not performed, the blood pressure values can be wrong. Zero adjustment of the pressure transducer is mandatory. In the PCCO calibration restore menu an old calibration factor may be used. Using an old calibration factor can lead to erroneous results. Make sure that the old calibration factor is still valid, before using this option. When the PiCCO plus is connected to a bedside monitor, perform a zero calibration of the PiCCO plus before calibration of the bedside monitor. After every change of AP Correction, a recalibration of the pulse contour analysis via a thermodilution measurement is necessary. Recalibration is recommended with significant changes in hemodynamic conditions, such as volume shifts or changes to medication. If the pulse contour parameters are not plausible, they should be checked by a thermodilution measurement. The continuous pulse contour cardiac output measurement will be recalibrated automatically. Recalibration is recommended with significant changes in hemodynamic conditions, such as volume shifts or changes to medication. CVP should be updated when a new value is obtained to accurately calculate SVR. Faulty measurements can be caused by incorrectly placed catheters, defective connections or sensors and by electromagnetic interference (e.g.: electric blankets, electric coagulation). The PiCCO plus is subject to specific precautions concerning EMC and is only allowed to be installed and used according the EMC advices contained in this User´s Manual. Displayed ITBV / GEDV can be erroneously high with an aortic aneurysm, in combination with thermodilution measurement in the femoral artery. Equipment that may be connected to the analogue or digital interface has to meet the corresponding IEC specifications (e.g.: IEC 950 for data processing devices and IEC 601 for electro medical devices). Furthermore, all configurations have to meet the system standard IEC 601-1-1. Anyone who connects additional devices to the signal input or signal output of the PiCCO plus is changing the system configuration and is responsible for the adherence of the standard IEC 601-1-1. All units of the device are protected against malfunction that may be caused by EMC and ESD emitting devices such as defibrillators or devices for electrosurgical procedures. Apart from intermittent measurement errors, this has no effect on the safety or function of the device. In case of a ‘reset’ caused by line power interruption or excessive EMC influence the PiCCO plus restarts automatically. After confirming the valid calibration, monitoring can be continued without any loss of data Do not expose the PiCCO plus to temperatures above 40 ºC or below 10 ºC as accuracy of the measured values may be affected. Do not place other equipment or containers with liquid on top of the PiCCO plus. At the end of the battery life, cells need to be recycled or disposed of properly.

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General Information - Blank page -

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Operator’s Manual PiCCO plus Version 7.1

Introduction

3.

Introduction Only the measurement of clinically relevant hemodynamic parameters results in correct diagnosis and appropriate therapy in critically ill patients. Today, intravascular pressure and cardiac output (CO) monitoring are frequently performed in the operating room and intensive care unit. Currently, CO is predominantly measured intermittently, although continuous measurement would be preferable. Continuous measurement appears to be a significant improvement in the hemodynamic monitoring of critically ill patients. The method for continuous cardiac output measurement should be as safe as possible, easy to use and it should be applicable without restrictions. The majority of current techniques for measuring continuous cardiac output are complex, cumbersome and expensive. One of the most common techniques for measuring continuous CO is the heat emitting thermodilution pulmonary artery catheter. Compared to this method, estimation of CO from the arterial pulse contour is less invasive and produces a real "beat to beat" signal. Additionally, pulse contour cardiac output (PCCO) monitoring is easily applicable to all critically ill patients. The arterial pulse contour method for measuring CO was originally described by Otto Frank in 1899[1]. Since then, a variety of pressure contour algorithms for estimating beat to beat stroke volume have been developed. The PiCCO plus is a device for continuous cardiac output measurement combined with volumetric assessment of cardiac preload and lung water monitoring without the need of a pulmonary artery catheter. The PULSION PiCCO plus computes the CO continuously, utilizing an improved arterial pulse contour analysis algorithm. The PCCO is calibrated by means of a transpulmonary thermodilution measurement. A bolus of normal saline or 5% dextrose in water is injected through a central venous catheter. A thermodilution curve is recorded by an arterial thermodilution catheter, which also serves for pressure monitoring. In addition to calibration of the PCCO, transpulmonary thermodilution also yields cardiac preload by means of global end-diastolic volume (GEDV) and an estimation of both, intrathoracic blood volume (ITBV) and extravascular lung water (EVLW) and various derived variables.

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Operator’s Manual PiCCO plus Version 7.1

Intermittent Thermodilution Measurement

4.

Intermittent Thermodilution Measurement

4.1

Principles of Cardiac Output Determination Cardiac output is determined using the well known Stewart-Hamilton formula. To accomplish thermodilution determination, a known volume of cold (at least 10°C lower than blood temperature) indicator is injected intravenously as quickly as possible. The recorded downstream temperature change is dependent on the flow and the volume through which the cold indicator has passed. As a result, a thermodilution curve can be recorded. The PiCCO plus detects the cold indicator in the arterial system (preferably in the femoral artery). Cardiac output (C.O.) by thermodilution is calculated as follows: C.O. = [(Tb – Ti) • Vi • K] / [∆Tb • dt] Tb: Ti: Vi: ∆Tb • dt: K:

4.2

(1)

Blood temperature before the injection of cold bolus Temperature of the injected indicator (injectate) Injection volume Area under the thermodilution curve Correction constants, made up of specific weights and specific heats of blood and injectate

Principles of Volume Calculation Specific volumes can be calculated by multiplying cardiac output with characteristic time variables of the thermodilution curve. The PULSION PiCCO plus determines the mean transit time (MTt) of the thermodilution curve as well as the exponential downslope time (DSt).

Figure 1: Schematic description of an indicator dilution curve and the time characteristics of interest

MTt DSt

Operation Manual PiCCO plus Version 7.1

= Mean transit time = Exponential downslope time

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Intermittent Thermodilution Measurement

MTt volume The product of CO and MTt represent the volume traversed by the indicator, i.e. total volume between the sites of injection and detection. This volume is often referred to as "needle to needle volume". DSt volume The product of CO and DSt represent the largest individual mixing volume in a series of indicator dilution mixing chambers.

Figure 2: Indicator mixing chambers within the cardiopulmonary system (schematic)

RAEDV: LAEDV: RVEDV: LVEDV: PBV: EVLW:

4.3

Right Atrial End-Diastolic Volume Left Atrial End-Diastolic Volume Right Ventricular End-Diastolic Volume Left Ventricular End-Diastolic Volume Pulmonary Blood Volume Extravascular Lung Water

Parameter Obtained by Transpulmonary Thermodilution The following parameters are derived by the PiCCO plus from a central venous indicator injection and transpulmonary detection with a thermistor catheter, and will be explained in the following chapters [2-8] The application of a pulmonary artery catheter is not necessary.

Parameter Cardiac Output, transpulmonary Global End-Diastolic Volume Extravascular Lung Water Global Ejection Fraction Pulmonary Vascular Permeability Index Cardiac Function Index Intrathoracic Blood Volume

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Absolute parameters

Indexed parameters

Abbr.

Unit

Abbr.

Unit

COa GEDV EVLW GEF

l/min ml ml %

CIa GEDI ELWI n.a.

l/min/m2 ml/m2 ml/kg

PVPI CFI ITBV

n.a. 1/min ml

n.a ITBI

ml/m2

Operator’s Manual PiCCO plus Version 7.1

Intermittent Thermodilution Measurement

4.3.1

Cardiac Output Transpulmonary The measurement of cardiac output by transpulmonary thermodilution (COa) has been validated by many clinical studies against the pulmonary arterial thermodilution and the Fick method [9-22]. The transpulmonary thermodilution curves are four to five times longer than those of the pulmonary artery. Compared to pulmonary artery thermodilution, the transpulmonary thermodilution measurement has only minimal ventilatory variations because of the longer passage time. As a result, COa provides a representative mean value over the ventilatory cycle and the reproducibility of COa measurement is around 5 % [14]. Therefore, three injection boluses are sufficient for an accurate determination of COa. Transpulmonary thermodilution cardiac output serves as the basic parameter for calculation of various blood volumes, explained below:

4.3.2

Global End-Diastolic Volume (GEDV) and Intrathoracic Blood Volume (ITBV) GEDV measurement using single thermodilution method Global End-Diastolic Volume is the sum of all end-diastolic volumes of the atria and the ventricles. Thus, GEDV is equivalent to preload volume of the total heart. GEDV can be determined by thermodilution at bedside [2-8]. GEDV = COa • (MTtTDa – DStTDa) MTt TDa: DSt TDa:

(2)

Mean transit time of the cold indicator from the site of injection to the site of detection Exponential downslope time of the arterial thermodilution curve

Cardiopulmonary or, more precisely, Intrathoracic blood volume measurement has been performed with indicator dilution techniques for over thirty years.

Operation Manual PiCCO plus Version 7.1

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Intermittent Thermodilution Measurement

ITBV estimation using single thermodilution method The PiCCO plus offers the possibility of assessing ITBV derived from Global End-Diastolic Volume (GEDV) determined by thermodilution measurement. GEDV correlates well with ITBV in both experimental and in clinical studies, as shown in figure 3[8]. Using regression analysis of GEDV (determined by thermodilution) and ITBV (determined by thermal-dye-dilution) a regression equation can be derived. Using this equation, ITBV (obtained without dye dilution) can be estimated [3, 5-8]: ITBV = 1.25 • GEDV

(3)

Figure 3: Structural regression analysis of the relation between Intrathoracic Blood Volume (ITBV) and Global End-Diastolic Volume (GEDV)

(Patho-) physiological significance of GEDV and ITBV The following figure (fig 4) demonstrates the relationship between GEDV index (GEDI) and Stroke Volume Index (SVI). In total 36 patients suffering from septic shock, who were in need of a volume challenge or an increase in dobutamine infusion were included. Hemodynamic parameters were evaluated in triplicate by the transpulmonary thermodilution technique. In total, 66 fluid challenges were done in 27 patients, and 28 increases in the dobutamine infusion rate were made in 9 patients. Volume loading induced a significant increase in central venous pressure (CVP), in Global EndDiastolic Volume Index (GEDI), Stroke Volume Index (SVI), and in Cardiac Index (CI). Changes in GEDI were correlated with changes in SVI, while changes in CVP were not. The pre-infusion GEDI was lower in the cases of positive response, and was negatively correlated with the percentage increase in GEDI and in SVI. Dobutamine infusion induced an increase in SVI and in CI but no significant change in CVP and in GEDI. These results demonstrate that the GEDI behaves as an indicator of cardiac preload [46].

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Operator’s Manual PiCCO plus Version 7.1