Datex-Ohmeda
S5 Monitors E-Modules Technical Reference Manual Edition 4 Nov 2012
Technical Reference Manual
747 Pages
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Datex-Ohmeda E-Modules Technical Reference Manual
Conformity according to the Council Directive 93/42/EEC concerning Medical Devices amended by 2007/47/EEC. CAUTION: U.S. Federal law restricts this device to sale by or on the order of a licensed medical practitioner. Outside the USA, check local laws for any restriction that may apply. All specifications subject to change without notice. Order code for the Datex-Ohmeda E-Modules Technical Reference Manual, paper: M1065282 Order code for the S/5 Technical Reference Manuals CD: M1220141 4th edition November 19, 2012
GE Healthcare Finland Oy Kuortaneenkatu 2, FI-00510 Helsinki Finland Tel: +358 10 39411 Fax: +358 9 1463310 www.gehealthcare.com 2012, 2011 General Electric Company. All rights reserved.
Responsibility of the manufacturer GE Healthcare Finland Oy (GE) is responsible for the effects on safety, reliability and performance of the equipment only if: • assembly, extensions, readjustments, modifications, servicing and repairs are carried out by personnel authorized by GE. • the electrical installation of the monitor room complies with appropriate requirements. • the equipment is used in accordance with the "User's Guide" and serviced and maintained in accordance with the “Technical Reference Manual”. The manufacturer reserves the right to change product specifications without prior notice. Although the information in this manual is believed to be accurate and reliable, the manufacturer assumes no responsibility for its use.
Trademarks S/5, D-lite, D-lite+, Pedi-lite, Pedi-lite+, Mini D-fend, D-fend, D-fend+, MemCard, ComBar, ComWheel, EarSat, FingerSat, FlexSat, PatientO2, Entropy and Patient Spirometry are trademarks of GE Healthcare Finland Oy. Datex, Ohmeda, and OxyTip+ are trademarks of GE Healthcare Finland Oy and Datex-Ohmeda, Inc. A portion of the Entropy software is derived from the RSA Data Security, Inc. MD5 Message-Digest Algorithm.
Masimo SET Masimo SET is a licensed trademark of Masimo Corporation. All other product and company names are property of their respective owners.
Product availability Some of the products mentioned in this manual may not be available in all countries. Please, consult your local representative for the availability.
Master Table of Contents
Datex-Ohmeda E-Modules M1065282
Description Respiratory Modules, E-sCAiOV, E-sCAiO, E-sCOV and E-sCO
1
Compact Airway Modules, E-CAiOVX, E-CAiOV,
2
E-CAiO, E-COVX, E-COV and E-CO PRESTN Modules, E-PRESTN, E-RESTN, E-PRETN
3
Patient Side Modules, E-PSM, E-PSMP rev. 01
4
Cardiac Output Modules E-COP rev. 01 and E-COPSv rev. 01
5
Pressure Module, E-P, Pressure Temp Module, E-PT
6
Dual Pressure Module, E-PP
7
Masimo Module, E-MASIMO
8
Nellcor Compatible Saturation Module, E-NSAT, E-NSATX
9
Single-width Airway Module, E-miniC
10
Tonometry Module, E-TONO
11
Entropy Module, E-ENTROPY
12
EEG Module, E-EEG rev.00 and EEG Headbox, N-EEG rev. 01
13
BIS Module, E-BIS rev. 01
14
NeuroMuscular Transmission Module, E-NMT
15
Device Interfacing Solution, N-DISxxx rev. 01
16
Interface Module, E-INT
17
Recorder Module, E-REC
18
Memory Module, E-MEM
19
Remote Controllers, K-REMCO rev. 01, K-CREMCO
20
Anesthesia record keeping keyboard, K-ARKB, Keyboard Interface Board, B-ARK and ARK Barcode Reader, N-SCAN
21
E-Modules, Spare Parts
22
i Document no. M1181405B
About this manual Notes to the reader This Technical Reference Manual is intended for service personnel and engineers who will service and maintain the Datex-Ohmeda E-Modules as well as the anesthesia record keeping keyboard, K-ARKB, remote controllers, K-REMCO and K-CREMCO, Device Interfacing Solution, N-DISxxx, keyboard interface board, B-ARK, and ARK barcode reader, N-SCAN. This Technical Reference Manual completes the S/5 Anesthesia Monitor and S/5 Critical Care Monitor Technical Reference Manual and the S/5 Compact Anesthesia Monitor and S/5 Compact Critical Care Monitor Technical Reference Manual. Later in this manual, the monitors may be referred to as AM, CCM, CAM and CCCM. The order code for the Datex-Ohmeda E-Modules Technical Reference Manual is M1065282. The order code for the S/5 Technical Reference Manuals CD is M1220141. S/5 AM, CCM Technical Reference Manual, S/5 CAM, CCCM Technical Reference Manual and Datex-Ohmeda E-Modules Technical Reference Manual are included on the CD. Each manual on the CD has an individual document number and is available for downloading from GE Common Document Library in Adobe Acrobat PDF format.
•
This Technical Reference Manual contains the information needed to maintain, service and troubleshoot these products. Instructions for visual and functional inspection, disassembly and reassembly as well as calibration of the modules are included. A service check form for each product is included in the slots.
•
In addition, this Technical Reference Manual contains detailed module specifications and descriptions on the technical performance and functioning of the modules.
•
Read the manual through and make sure that you understand the procedures described before servicing the modules. To avoid risks concerning safety or health, strictly observe the warning indications. If you need any assistance concerning the service, please do not hesitate to contact your authorized distributor.
For information on safety precautions and symbols on equipment, installation, planned maintenance and interfacing, refer to the AM and CCM Technical Reference Manual or the CAM and CCCM Technical Reference Manual. The manufacturer reserves the right to change product specifications without prior notice. Although the information in this manual is believed to be accurate and reliable, the manufacturer assumes no responsibility for its use. GE Healthcare assumes no responsibility for the use or reliability of its software in equipment that is not furnished by GE Healthcare.
Related documentation S/5 AM, CCM Technical Reference Manual S/5 CAM, CCCM Technical Reference Manual For more specific information about the clinical aspects refer to: S/5 monitor’s User’s Guide S/5 monitor’s User’s Reference Manual
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Conventions used Throughout this manual, the following conventions are used to distinguish procedures or elements of text:
Sign the check form after performing the procedure.
Hard Keys
Hard key names on the Command Board, the Remote Controller and modules are written in the following way: ECG.
Menu Items
Menu items are written in bold italic: ECG Setup.
‘Messages’
Messages displayed on the screen are written inside single quotes: ‘Please wait’.
“Sections”
When referring to different sections in the same manual, the section name is enclosed in double quotes: section “Cleaning and Service.”
“Other documents” When referring to different documents, the document name is enclosed in double quotes: refer to “User’s Reference Manual”. Hypertext links Hypertext links on PDF versions are written in blue color. WARNING
Warnings are written in the following way:
WARNING
Make sure that the electrodes, sensor and connectors do not touch any electrically conductive material, including earth.
CAUTION
Cautions are written in the following way:
CAUTION
The module electronics can only be repaired and calibrated at the factory.
NOTE
Notes are written in following way: NOTE: Handle all PC boards by their edges. In this manual, the word “select” means choosing and confirming.
Revision history Revision
Date
Comment
1st edition
10 May 2011
Initial
2nd edition
22 Sep 2011
Order code for paper manual added.
3rd edition
19 June 2012
E-PSM rev. 01, E-PSMP rev. 01, E-COP rev.01 and E-COPSv rev. 01 update.
4th edition
19 Nov 2012
Respiratory Modules E-sCAiOV, E-sCAiO, E-sCOV and E-sCO added .
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GE Healthcare Respiratory Modules, E-sCAiOV, E-sCAiO, E-sCOV, E-sCO
Technical Reference Manual Slot
Conformity according to the Council Directive 93/42/EEC concerning Medical Devices amended by 2007/47/EEC. CAUTION: U.S. Federal law restricts this device to sale by or on the order of a licensed medical practitioner. Outside the USA, check local laws for any restriction that may apply. All specifications subject to change without notice. Document number M1214853C June 21, 2012
GE Healthcare Finland Oy Kuortaneenkatu 2, FI-00510 Helsinki Finland Tel: +358 10 39411 Fax: +358 9 1463310 www.gehealthcare.com 2012 General Electric Company. All rights reserved.
Table of contents
Table of contents Introduction
1
1
3
Technical specifications 1.1 1.2 1.3
1.4
2
Functional description 2.1
2.2
3
Physical characteristics... 3 Operating characteristics... 3 Airway gases... 3 1.3.1 General characteristics... 3 1.3.2 Respiration rate... 3 1.3.3 Carbon dioxide... 4 1.3.4 Oxygen... 4 1.3.5 Nitrous oxide... 4 1.3.6 Anesthetic agents... 5 1.3.7 Non-disturbing gases... 5 1.3.8 Gas cross effects... 5 Patient Spirometry... 6 1.4.1 General characteristics... 6 1.4.2 Airway pressure... 6 1.4.3 Airway gas flow... 6 1.4.4 Tidal volume... 6 1.4.5 Minute volume... 7 1.4.6 Compliance... 7 1.4.7 Airway resistance... 7 1.4.8 Inspiration to expiration ratio... 7 Measurement principle... 8 2.1.1 CO2, N2O, and agent measurement... 8 2.1.2 O2 measurement... 10 2.1.3 Patient spirometry... 10 Main components... 12 2.2.1 Controls and connectors... 12 2.2.2 Gas sampling system... 13 2.2.3 MiniTPX measuring unit... 16 2.2.4 MiniOM Oxygen sensor... 17 2.2.5 MiniPVX measuring unit... 19 2.2.6 CPU board... 20 2.2.7 MiniOM board... 20 2.2.8 MiniPVX board... 21 2.2.9 Main Component Interactions... 21
Service Procedures 3.1
8
22
Replacement of planned maintenance parts... 23 3.1.1 Required parts... 23 3.1.2 Planned Maintenance Kits... 23
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3.2 3.3
3.4 3.5
4
Troubleshooting 4.1 4.2
4.3 4.4 4.5
5
5.2
47
Visual inspection... 47 Troubleshooting checklist... 47 4.2.1 Gas sampling system troubleshooting... 48 4.2.2 MiniOM Measuring unit troubleshooting... 48 4.2.3 MiniTPX Measuring unit troubleshooting... 48 4.2.4 MiniPVX Measuring unit troubleshooting... 48 4.2.5 CPU board troubleshooting... 49 Service Interface... 49 Messages... 50 4.4.1 Gas measurements... 50 4.4.2 Spirometry... 53 Troubleshooting charts... 54 4.5.1 CO2 measurement... 54 4.5.2 Patient spirometry... 54
Spare parts 5.1
6
3.1.3 Replacement procedures... 23 Visual inspections... 24 Functional check... 25 3.3.1 Test setup... 25 3.3.2 Procedure... 25 3.3.3 Test completion... 30 Disassembly and reassembly... 30 3.4.1 Disassembly guidelines... 30 3.4.2 Disassembly and reassembly procedure... 32 Adjustments and calibration... 42 3.5.1 Sample Flow Rate Adjustment... 42 3.5.2 Gas Calibration... 43 3.5.3 Spirometry Calibration... 45
56
Ordering parts... 56 5.1.1 Planned Maintenance Kits... 56 Spare parts for E-sCAiOV, E-sCAiO, E-sCOV, E-sCO... 57 5.2.1 Front covers... 59
Earlier revisions
Appendix A:
Service check form
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Respiratory Modules, E-sCAiOV, E-sCAiO, E-sCOV, E-sCO
Introduction This document provides information for the maintenance and service of the CARESCAPE Respiratory modules, E-sCO, E-sCOV, E-sCAiO and E-sCAiOV. The CARESCAPE Respiratory modules are single width plug-in modules. The CARESCAPE Respiratory modules provide airway and respiratory measurements. Letters in the module name stand for: C = CO2 and N2O, O = patient O2, V = patient spirometry, A = anesthetic agents, and i = agent identification
Table 1 Modules
Options for CARESCAPE Respiratory modules Parameters / measurements CO2
N2O
O2
E-sCOV
X
X
X
E-sCO
X
X
X
E-sCAiOV
X
X
X
X
X
E-sCAiO
X
X
X
X
X
Anesthetic agents
Agent ID Spirometry X X
NOTE: Anesthetic agents and N2O values are not displayed with ICU and ED software packages, but when present in the module they are calculated for compensation of CO2 and O2.
Figure 1 (1)
Airway gases measurement setup
CARESCAPE Respiratory Module
(2)
Gas sample, gas sampling line connector on the water trap
(3)
Gas sampling line
(4)
Gas sampling line connector on the airway adapter; place the connector upwards
(5)
Airway adapter with sampling line connector
(6)
Heat and moisture exchanger with filter (HMEF) (optional)
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System compatibility The CARESCAPE Respiratory Modules can be used for respiratory monitoring in the following S/5 monitors:
S/5 Anesthesia Monitor, software versions L-ANE06(A) 24.1 or later
S/5 Critical Care Monitor, software versions L-ICU06(A) 24.1 or later
S/5 Compact Anesthesia Monitor, software versions L-CANE05(A) 19.6 or later
S/5 Compact Critical Care Monitor, software versions L-CICU05(A) 19.6 or later
NOTE: Low sample gas flow situation is indicated with the message Replace D-Fend in the L-xxx06(A) software versions 24.1 and L-xxx05(A) software versions 19.6. NOTE: The CARESCAPE Respiratory Modules cannot be used in the S/5 Extension Frame.
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1
Technical specifications
1.1 Physical characteristics Size (H x W x D) Weight Power consumption
112 x 37 x 205 mm ( 4.4 x 1.5 x 8.7 in) 0.75 kg (1.5 lb) 3.9 W
1.2 Operating characteristics Warm-up time - CO2, O2 and N2O measurements:
1 minute
-Anesthetic agent measurement and identification: 5 minutes Gas sampling rate: 120 ±20 ml/min Automatic compensation for ambient pressure. Operating conditions Ambient temperature: +10°C to +40°C Ambient pressure: 660 mbar to 1060 mbar Ambient humidity: 10%RH to 98%RH, non-condensing
1.3 Airway gases 1.3.1 General characteristics Specifications are valid at the following normal operating conditions: Ambient temperature: +18°C to +28°C, within ±5°C of calibration Ambient pressure: 660 mbar to 1060 mbar, ±67 mbar of calibration Ambient humidity: 20%RH to 80%RH, non-condensing, ±20%RH of calibration Sampling line length: 2, 3 and 6 meters Respiration rate: 4 to 70 breaths/minute (Halothane 4 to 50 breaths/minute) Airway pressure: -20 mbar to +100 mbar Module operating time: >20 minutes continuously NOTE: The displayed ranges of parameter values depend on the host device. For more information, refer to the host device’s user documentation.
1.3.2 Respiration rate Breath detection:
1 vol% change in CO2 level
Measurement range: 4 to 100 breaths/min Accuracy at 4 to 20 breaths/min: ±1 breath/min at 20 to 100 breaths/min: ±5% RR value is updated breath-by-breath.
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1.3.3 Carbon dioxide Measurement range: Accuracy: Total system response time: Rise time: CO2 drift:
0 vol% to 15 vol%, 0 kPa to 15 kPa, 0 mmHg to 113 mmHg ±(0.2 vol% +2% of reading) < 3.0 s < 260 ms < 0.1 vol%
EtCO2 and FiCO2 values are updated breath-by-breath. Description of test method, data rate, and method of ET-calculation The module uses gas concentration waveforms with data rate of 25Hz to calculate end-tidal (ET) gas readings. The module finds the time instant of the highest CO2 concentration in each breath. Concentration at that instant is the ET CO2 reading. Because nitrous oxide and anesthetic agents are measured by the same sensor as CO2, the ET-readings of those gases are obtained directly at the time instant of ET CO2. For calculating ET-readings of oxygen, the module synchronizes the O2-waveform with the CO2 waveform. The ET-reading of O2 is then determined as O2-concentration at the time instant of ET CO2. If no breaths are detected for a given time (20s, for example), an apnea situation is triggered. During apnea, the ET values are updated every two seconds to the current concentration of each gas. The rated respiration rate range and the corresponding end-tidal gas reading accuracy were tested with reference gases of known concentrations. The test gases were fed to the gas sampling system of the module through an electrically actuated valve with very low internal volume. Depending on its actuation status, the valve directed either room air or a test gas to the gas sampling line. The desired respiration rates were set by the electrical actuating times of the valve. The measurement accuracy of the end-tidal gas readings was tested using gas sampling lines of 3 meter length, connected to the gas sample port on the D-fend Pro water trap. The gas sampled to the sampling line was switched from room air to the test gases using an electrically actuated valve with low internal dead space to generate step changes in the gas concentrations. The electric actuating signal of the valve was generated using a higly accurate signal generator to accurately control the simulated respiration rate. The electronic sampling rate of the gas sensor signals is 25Hz, equaling a new data point on the gas waveform traces every 40 milliseconds.
1.3.4 Oxygen Measurement range: Accuracy: Total system response time: Rise time: O2 drift:
0 vol% to 100 vol% ±(1 vol% +2% of reading) < 3.0 s < 260 ms < 0.3 vol%
EtO2 and FiO2 values are updated breath-by-breath.
1.3.5 Nitrous oxide Measurement range: Accuracy: at (0 < N2O < 85 vol%)
0 vol% to 100 vol%
Total system response time: Rise time: N2O drift:
< 3.0 s < 320 ms < 0.3 vol%
±(2 vol% +2% of reading)
EtN2O and FiN2O values are updated breath-by-breath.
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1.3.6 Anesthetic agents Measurement range: Sevoflurane: 0 vol% to 8 vol% Desflurane: 0 vol% to 20 vol% Isoflurane, enflurane, halothane: 0 vol% to 6 vol% Accuracy: ±(0.15 vol% +5% of reading) Total system response time: < 3.1 s (< 3.5 s for Halothane) Rise time: < 420 ms (< 800 ms for Halothane) Hal drift: < 0.1 vol% Enf drift: < 0.1 vol% Iso drift: < 0.1 vol% Sev drift: < 0.1 vol% Des drift: < 0.3 vol% EtAA and FiAA values are updated breath-by-breath. The module automatically identifies the anesthetic agent present in the sampled gas and measures the concentration of the identified agent. Identification threshold: 0.15 vol% Identification time: < 20 s The module automatically identifies mixtures of two anesthetic agents present in the sampled gas and measures the concentrations of the two identified agents. Identification threshold for the 2nd agent at 1 MAC of the 1st agent:
0.2 vol% +10% of the concentration of the 1st agent
1.3.7 Non-disturbing gases A gas is considered non-disturbing if its effects to the measured gas are as follows: CO2: < 0.2 vol% O2, N2O:
< 2 vol%
Anesthetic agents:
< 0.15 vol%
The following gases are non-disturbing when tested according to ISO21647(2004B): ethanol, acetone, isopropanol, methane, nitrogen, carbon monoxide, nitric oxide, freon R134A (for CO2, O2 and N2O), water vapor. The effects caused by N2O to the measurement of CO2, O2 and anesthetic agents are automatically compensated for. The effects caused by anesthetic agents to the measurement of CO2 and N2O are automatically compensated for.
1.3.8 Gas cross effects Helium (50 vol%):
Decreases CO2 readings by less than 0.5 vol% at 5 vol% of CO2
Xenon (80 vol%):
Decreases CO2 readings by less than 0.5 vol% at 5 vol% of CO2
Decreases O2 readings by less than 2 vol% at 50 vol% of O2 Decreases O2 readings by less than 1.5 vol% at 14 vol% of O2
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1.4 Patient Spirometry 1.4.1 General characteristics These specifications are valid in the following operating conditions: The module has been operating continuously for 10 minutes Airway adapter, adult: D-lite Airway adapter, pediatric: Pedi-lite Respiration rate - adults: 4 to 35 breaths/min - pediatric patients: 4 to 70 breaths/min I:E ratio: 1:4.5 to 2:1 Airway humidity: 10 %RH to 100 %RH Ambient temperature: +10°C to +40°C Ambient pressure: 660 mbar to 1060 mbar Ambient humidity: 10 %RH to 98 %RH (non-condensing) NOTE: The displayed ranges of parameter values depend on the host device. For more information, refer to the host device’s user documentation.
1.4.2 Airway pressure Measurement range:
-20 cmH2O to +100 cmH2O
Accuracy:
±1 cmH2O
Time resolution: 10 ms Values calculated from the measured airway pressure data: Peak pressure (Ppeak) Plateau pressure (Pplat) Mean pressure (Pmean) Positive end expiratory pressure (PEEPtot, or PEEPi and PEEPe) Static positive end expiratory pressure (static PEEPe and static PEEPi)
1.4.3 Airway gas flow Measurement range - adults: -100 l/min to +100 l/min - pediatic patients: -25 l/min to +25 l/min Time resolution: 10 ms Flow measurement has automatic compensation for airway pressure and effects caused by variation in the concentrations of the gas components measured by the module.
1.4.4 Tidal volume The module calculates the volume by integrating the measured gas flow over time. Tidal volumes (TVinsp and TVexp) are obtained as the change of volume during inspiration and expiration. Measurement range - with D-lite: - with Pedi-lite: Accuracy - with D-lite: - with Pedi-lite:
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150 ml to 2000 ml 5 ml to 300 ml ±6% or 30 ml (whichever is greater) ±6% or 4 ml (whichever is greater)
Respiratory Modules, E-sCAiOV, E-sCAiO, E-sCOV, E-sCO
1.4.5 Minute volume The module calculates the inspired and expired minute volumes as the sum of inspired (MVinsp) and expired (MVexp) gas volume during one minute. Measurement range - with D-lite: 2 l to 20 l - with Pedi-lite: 0.5 l to 5 l
1.4.6 Compliance The module calculates both the compliance (Compl) and static compliance (static Compl). Compliance is calculated by dividing the expired gas volume (TVexp) by the change in the airway pressure (Pplat PEEPtot). Static compliance is calculated by dividing TVexp by the difference of static Pplat and static PEEPtot. Measurement range - adults:
4 ml/cmH2O to 100 ml/cmH2O
- pediatric patients:
1 ml/cmH2O to 100 ml/cmH2O
1.4.7 Airway resistance The module calculates the airway resistance (Raw) by solving the lung model equation P(t) = Raw * F(t) + V(t) / Compl + PEEPtot where: P(t), F(t) and V(t) are the time dependent waveforms of pressure, flow, and volume, respectively. Measurement range: 0 cmH2O/l/s to 40 cmH2O/l/s
1.4.8 Inspiration to expiration ratio The module measures ratio of the inspiratory and expiratory time (I:E). The inspiratory time is the time from the start of inspiration to the start of expiration. The end inspiratory pause, if one exists, is included in the inspiration. Accordingly, expiratory time is the time from the start of expiration to the start of the next inspiration.
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2
Functional description
2.1 Measurement principle 2.1.1 CO2, N2O, and agent measurement MiniTPX is a side stream gas analyzer, measuring real time concentrations of CO2, N2O, and anesthetic agents (Halothane, Enflurane, Isoflurane, Desflurane, and Sevoflurane).
Figure 2
MiniTPX sensor principle
Anesthetic agents or mixtures of two anesthetic agents are automatically identified, and concentrations of the identified agents are measured. MiniTPX also detects mixtures of more than two agents and issues an alarm. MiniTPX is a non-dispersive infrared analyzer, measuring absorption of the gas sample at seven infrared wavelengths, which are selected using optical narrow band filters. The infrared radiation detectors are thermopiles. Concentrations of CO2 and N2O are calculated from absorption measured at 3-5 m.
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Figure 3
Absorbance of N2O and CO2
Identification of anesthetic agents and calculation of their concentrations is performed by measuring absorptions at five wavelengths in the 8-9 m band and solving the concentrations from a set of equations.
Figure 4
Infrared absorbance of AAs
The measuring accuracy is achieved utilizing numerous software compensations. The compensation parameters are determined individually for each MiniTPX during the factory calibration.
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2.1.2 O2 measurement The differential oxygen measuring unit uses the paramagnetic principle in a pneumatic bridge configuration. The signal picked up with a differential pressure transducer unit is generated in a measuring cell with a strong magnetic field that is switched on and off at a main frequency of 164 Hz. The output signal is a DC voltage proportional to the O2 concentration difference between the gas to be measured and the air reference.
Figure 5
O2 measurement principle
2.1.3 Patient spirometry In mechanical ventilation, breaths are delivered to the patient by a ventilator with a proper tidal volume (TV), respiration rate (RR), and inspiration / expiration ratio in time (I:E) determined by the settings of the ventilator. The Patient Spirometry monitors patient ventilation.
The following volume parameters are displayed:
Expiratory and inspiratory tidal volume (TV) in ml Expiratory and inspiratory minute volume (MV) in l/min Expiratory spontaneous minute volume in l/min Inspiration/expiration ratio (I:E)
The following airway pressure parameters are displayed:
Peak pressure (Ppeak) Mean airway pressure (Pmean); available only in S/5 Critical Care and Compact Critical Care monitors End inspiratory pressure (Pplat) PEEPi, PEEPe; available only in S/5 Critical Care and Compact Critical Care monitors Total positive end expiratory pressure (PEEPtot); available only in S/5 Anesthesia and Compact Anesthesia monitors Real time airway pressure waveform (Paw) Static Positive end expiratory pressures (Static PEEPi and Static PEEPe); available only in S/5 Critical Care and Compact Critical Care monitors Static Plateau pressure (Static Pplat); available only in S/5 Critical Care and Compact Critical Care monitors Static Compliance (Static Compl); available only in S/5 Critical Care and Compact Critical Care monitors
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PEEP, Ppeak, Pmean, and Pplat are measured by a pressure transducer on the MiniPVX board. Ambient pressure is used as a reference in measurement. The pressure measurement is made from the airway part that is closest to the patient between the patient circuit and intubation tube. PEEPi=intrinsic PEEP, PEEPtot-PEEPe Static pressure measurement maneuvers are automatically identified based on an increased zero flow period at the end of the inspiration or expiration. Static Compliance is calculated, if Static PEEP and Static Pplat measurements were made within a 2 minute period.
The following airway flow parameters are displayed: Real time flow waveform (V') Compliance (Compl) Airway resistance (Raw) Pressure volume loop Flow volume loop The measurement is based on measuring the kinetic gas pressure and is performed using the Pitot effect. A pressure transducer is used to measure the Pitot pressure. The pressure signal obtained is linearized and corrected according to the density of the gas. Speed of flow is calculated from these pressure values and the TV value is then integrated. The MV value is calculated and averaged using TV and RR (respiratory rate) values.
D-lite Patient Spirometry uses specific sensors called D-lite+/D-lite and Pedi-lite+/Pedi-lite flow sensors. Different types of sensors are available: adult sensor for measuring adults and pediatric sensor for children. Both are available as reusable and disposable versions. D-lite and Pedi-lite adapters are designed to measure kinetic pressure by a two-sided Pitot tube. Velocity is calculated from pressure difference according to Bernoulli's equation. Flow is then determined using the calculated velocity.
(from Bernoulli's equation)
Formula 1
where: V’ = flow (l/min), v = velocity (m/s), A = cross area (m2), dP = pressure difference (cmH2O), = density (kg/m3) Finally, the volume information is obtained by integrating the flow signal.
Compliance and airway resistance Compliance is calculated for each breath from the equation
Formula 2 Compliance describes how large a pressure difference is needed to deliver a certain amount of gas to the patient. The airway resistance, Raw, is calculated using an equation that describes the kinetics of the gas flow between the lungs and the D-lite. The equation states that the pressure at the D-lite can at any moment of the breath be approximated using the equation
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Formula 3 where P(t), V’(t) and V(t) are the pressure, flow and volume measured at the D-lite at a time t, Raw is the airway resistance, Compl is the compliance and PEEPe+PEEPi is the total positive end expiratory pressure (PEEPtot).
2.2 Main components The respiratory modules consist of:
• • • • •
Gas sampling system MiniTPX measuring unit MiniOM measuring unit MiniPVX measuring unit CPU board
2.2.1 Controls and connectors
Figure 6
Front of CARESCAPE Respiratory Module, E-sCAiOV, and the back of the module
(1)
D-fend Pro water trap
(2)
Gas sample, sampling line connector on the water trap
(3)
Water trap container
(4)
Connectors for Patient Spirometry
(5)
Gas exhaust, connector for the gas exhaust line (sampling gas out
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