Gas Module II, SE SE with Spirometry and 3 Service Manual Addendum

AION™ is a trademark of Artema Medical AB. D-Lite™ is a trademark of GE Medical Systems Information Technologies. DRYLINE™ is a trademark of Artema Medical AB. Gas Module II® is a U.S. registered trademark of Mindray DS USA, Inc. Gas Module SE™ is a U.S. trademark of Mindray DS USA, Inc. Nafion™ is a trademark of Perma Pure Inc. Passport® XG is a U.S. registered trademark of Mindray DS USA, Inc. Passport 2® is a U.S. registered trademark of Mindray DS USA, Inc. Spectrum® is a U.S. registered trademark of Mindray DS USA, Inc. Spectrum OR™ is a U.S. trademark of Mindray DS USA, Inc.

Copyright © Mindray DS USA, Inc., 2008. All rights reserved. Contents of this publication may not be reproduced in any form without permission of Mindray DS USA, Inc.

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Gas Module Service Manual Addendum

Table of Contents

Introduction ... v Warnings, Precautions and Notes... vi Warnings ... vi Caution ... vii

Theory Of Operation... 1 - 1 Gas Sampling System... 1 - 2 Water Trap... 1 - 3 Zero Valve and Absorber ... 1 - 4 Nafion™ Tube ... 1 - 4 Gas Analyzers ... 1 - 4 Sample Flow Differential Pressure Transducer ... 1 - 4 Working Pressure Transducer... 1 - 4 Pneumatic Unit ... 1 - 4 Connection Block... 1 - 4 Occlusion Valve ... 1 - 5 Sampling Pump and Damping Chamber... 1 - 5 Anesthetic Agent Sensor ... 1 - 6 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 1 - 6 Gas Module 3 ... 1 - 8 O2 Sensor ... 1 - 11 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 1 - 11 Gas Module 3 ... 1 - 12 CPU Board... 1 - 14 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 1 - 14 Gas Module 3 ... 1 - 15 O2 Board ... 1 - 16 Communication Interface Board... 1 - 17 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 1 - 17 Gas Module 3 ... 1 - 18 Electrical Wiring Diagram... 1 - 19 Gas Module 3 Electronics ... 1 - 20 Power Supply ... 1 - 22 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 1 - 22 Gas Module 3 ... 1 - 23 Spirometry (Gas Module SE with Spirometry Only) Overview ... 1 - 24 Measured Parameters ... 1 - 24 Measurement Principles ... 1 - 25 PVX Measuring Unit ... 1 - 25

Specifications... 2 - 1 Performance Specifications ... 2 - 2 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 2 - 2 Gas Module 3 ... 2 - 3 Gas Measurements ... 2 - 6 Normal Conditions ... 2 - 6 Non-disturbing Gases ... 2 - 6 Disturbing Gases ... 2 - 7 Gas Module 3 Interference Specifications... 2 - 7 CO2 ... 2 - 8 O2... 2 - 9 N2O ... 2 - 10 Anesthetic Agents ... 2 - 10 Accuracy specifications at conditions exceeding normal... 2 - 12

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Table of Contents

ISO Mode Accuracy specifications for Gas Module 3 ... 2 - 13 Patient Spirometry ... 2 - 15 Normal Conditions for Gas Module SE with Spirometry ... 2 - 15 Accuracy specifications at conditions exceeding normal... 2 - 16 Power Input Ratings... 2 - 17 Environmental Conditions... 2 - 17 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 2 - 17 Gas Module 3 ... 2 - 17 Physical Characteristics ... 2 - 18 Gas Module II ... 2 - 18 Gas Module SE ... 2 - 18 Gas Module 3 ... 2 - 18 Agency Compliance... 2 - 18 Gas Module II ... 2 - 18 Gas Module SE ... 2 - 19 Gas Module 3 ... 2 - 19

Repair Information ... 3 - 1 Introduction ... 3 - 1 Safety Precautions... 3 - 2 Troubleshooting ... 3 - 2 General Troubleshooting Guidelines ... 3 - 2 Gas Module Technical Troubleshooting ... 3 - 3 Patient Spirometry Trouble Shooting... 3 - 6 Exchange Program ... 3 - 7 Equipment and Special Tools Required ... 3 - 8 Disassembly Instructions... 3 - 9 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 3 - 9 Gas Module 3 ... 3 - 12 Mounting Hardware and Accessories ... 3 - 13 Passport XG/Gas Module Mounting ... 3 - 13 Expert/Gas Module Mounting... 3 - 15 Passport 2/Spectrum/Spectrum OR Gas Module Mounting ... 3 - 17 Gas Module II/Gas Module SE Accessories ... 3 - 21 Gas Module SE with Spirometry Accessories ... 3 - 22 Gas Module 3 Accessories ... 3 - 23

Replacement Parts ... 4 - 1 Introduction ... 4 - 1 Available Replacement Parts and Sub-Assemblies ... 4 - 1 Exchange Program... 4 - 2 Replacement Parts Pricing Information ... 4 - 2 Ordering Information ... 4 - 3 Abbreviations ... 4 - 4 Isometric Drawing and Parts Lists ... 4 - 5

Calibration ... 5 - 1 Introduction ... 5 - 1 Warnings and Guidelines ... 5 - 1 Test Equipment and Special Tools Required... 5 - 2 Power-Up Verification ... 5 - 2 Passport XG Configuration for Gas Module ... 5 - 2 Expert Configuration for Gas Module... 5 - 3 Passport 2/Spectrum/Spectrum OR Configuration for the Gas Module ... 5 - 4 Gas Module 3 Pneumatic Leakage Test... 5 - 5

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Table of Contents

Gas Module 3 Zero Reference Valve Test ... 5 - 5 Calibration... 5 - 6 Passport XG Gas Calibration ... 5 - 6 Expert Gas Module Calibration ... 5 - 8 Gas Monitor Calibration - Passport 2/Spectrum/Spectrum OR ... 5 - 10 Power Supply PC Board Calibration ... 5 - 16 Patient Spirometry Calibration Measurement (Spectrum OR only)... 5 - 18 Patient Spirometry Leak Test Verification (Spectrum OR Only)... 5 - 20 Gas Module Leakage Current Checks... 5 - 21

Preventive Maintenance... 6 - 1 Preventive Maintenance Introduction ... 6 - 1 Preventive Maintenance Schedule ... 6 - 1 Performance Verification... 6 - 2 Perform as required, or at 6 month intervals... 6 - 2 Perform as required, or 1 Year intervals ... 6 - 2 Patient Spirometry Leak Test Verification (Spectrum OR Only)... 6 - 2 Mechanical / Physical / Visual Inspection ... 6 - 2 Perform at 6 month intervals... 6 - 2 Consumable Item Replacement ... 6 - 2 Replace at 1 month intervals ... 6 - 2 Replace at 2 month intervals ... 6 - 2 Replace at 12 month intervals ... 6 - 2 Replace at 24 month intervals ... 6 - 2 Internal Adjustments/Calibration... 6 - 3 Perform at 12 month intervals or as required... 6 - 3 Patient Spirometry Calibration Measurement (Spectrum OR only)... 6 - 3 Care and Cleaning of Gas Module ... 6 - 4 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry ... 6 - 4 Gas Module 3 ... 6 - 5

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Introduction

Introduction

Introduction The Gas Module is a companion to several Patient Monitors. It is capable of automatically identifying and measuring five anesthetic agents (Desflurane, Enflurane, Sevoflurane, Halothane and Isoflurane), as well as N2O, CO2 and O2. The unit monitors all gases via sidestream sampling. The following models are referenced in this manual: Gas Module II, Gas Module SE, Gas Module SE with Spirometry, and Gas Module 3. When information is common to all models, the generic name “Gas Module” is used. Information that is unique to a specific model is identified accordingly. The system connects to the Patient Monitor via an RS232 connector. A special “Y” shaped power cord is used to supply AC voltage to both the Gas Module and the Monitor power supply. All Gas Module data displays on the monitor screen. All user commands are entered on the monitor and then electronically transmitted to the Gas Module. This addendum provides Gas Module information on theory of operation, specifications, repair, parts, calibration and preventive maintenance. For related information on the Patient Monitor, refer to the associated Service Manual and Operating Instructions. • Passport XG Operating Instructions • Passport 2 Operating Instructions (Domestic) • Passport 2 Operating Instructions (International) • Expert Operating Instructions (Domestic) • Spectrum Operating Instructions (Worldwide) • Spectrum OR Operating Instructions (Worldwide) NOTE:

The Gas Module SE with Spirometry can only be used with the Spectrum OR monitor.

NOTE:

The Gas Module 3 can only be used with Passport 2, Spectrum, and Spectrum OR monitors.

WARNING: Calibration gas is considered Dangerous Goods/Hazardous Materials per I.A.T.A. and D.O.T. Regulations. It is a violation of federal and international law to offer any package or over pack of dangerous goods for transportation without the package being appropriately identified, packed, marked, classified, labeled and documented according to D.O.T. and I.A.T.A. regulations. Please refer to the applicable I.A.T.A. Dangerous Goods Regulations and/or the Code of Federal Regulations 49 (Transportation, Parts 171-180) for further information.

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Introduction

Warnings, Precautions and Notes

Warnings, Precautions and Notes Please read and adhere to all warnings, precautions and notes listed here and in the appropriate areas throughout this manual. A WARNING is provided to alert the user to potential serious outcomes (death, injury, or serious adverse events) to the patient or the user. A CAUTION is provided to alert the user to use special care necessary for the safe and effective use of the device. They may include actions to be taken to avoid effects on patients or users that may not be potentially life threatening or result in serious injury, but about which the user should be aware. Cautions are also provided to alert the user to adverse effects on this device of use or misuse and the care necessary to avoid such effects. A NOTE is provided when additional general information is applicable.

Warnings WARNING: Always Remove Power from the Gas Module BEFORE Disassembly. WARNING: Remove Power from the Gas Module BEFORE removing the Enclosure. WARNING: If the water trap breaks or becomes damaged during operation, there is a risk that bacteria and/or mucus may contaminate the Gas Module. WARNING: The airway adapter and sampling line are intended for single use only. WARNING: The water trap, sampling line, and airway adapter should be disposed of in accordance with local regulations for contaminated and biologically hazardous items. WARNING: To avoid high sampling flow with the Gas Module 3, do not use Adult/Pediatric water traps and/or sampling lines with neonates. WARNING: Connect only approved gas sampling lines to the water trap. WARNING: The Gas Module must not be used with flammable anesthetic agents. WARNING: The use of gas sampling accessories other than specified may cause significant measurement errors and patient risk. WARNING: With the Gas Module 3, use only Neonate sampling lines and water traps for Neonate patients. Do not use Neonate sampling lines and water traps for Adult/Pediatric patients. WARNING: Do not allow the sampling tubing to become kinked. WARNING: Do not reuse disposable devices.

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Cautions

Introduction

WARNING: Trace Gas Hazard – When using the optional Gas Module, a health hazard exists when trace amounts of vaporized anesthetic agents are chronically inspired by operating room personnel. See Appendix A in NFPA 56A on Inhalation Anesthetics. During any procedure where such agents are employed, the Gas Module exhaust output should be connected to a medical gas-scavenging system. WARNING: When monitoring CO2, connection from the exhaust port to the hospital’s waste gas-scavenging system is recommended to prevent exposure of hospital personnel to the patient’s respiratory sample. WARNING: Connection of the Gas Module exhaust port to the hospital’s waste gas-scavenging system is recommended to prevent exposure of hospital personnel to the patient’s respiratory sample. Vacuum (negative pressure) should not exceed 1 mmHg at the Gas Module exhaust fitting. Excessive scavenge vacuum may result in damage to the Gas Module’s internal pump. WARNING: Equipment not suitable for use in the presence of a flammable anesthetic mixture with air or with nitrogen or nitrous oxide. WARNING: Do not connect devices that are not specified as part of the system. WARNING: Do not clean the Gas Module while it is on and/or plugged in. WARNING: The contents of the water trap should be handled as a potential infection hazard.

Cautions CAUTION:

The internal sampling system of the Gas Module does not need to be cleaned or sterilized. There is no reverse flow back to the patient. If the internal sampling system is suspected to be clogged or dirty, the module should be serviced by an authorized service person only.

CAUTION:

If the dust filter for the fan cannot be cleaned or is damaged, replace it with part number 0378-00-0040. Use of another type of filter may decrease the cooling effectivity and cause damage to the Gas Module.

CAUTION:

Do not disinfect or open the water trap. Do not touch the water trap membrane.

CAUTION:

Dispose of the water trap in accordance with hospital policy.

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Introduction

Cautions

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1.0

Theory Of Operation

Contents of this chapter ... Page 1.1 Gas Sampling System ... 1-2 1.2 Anesthetic Agent Sensor ... 1-6 1.3 O2 Sensor ... 1-11 1.4 CPU Board ... 1-14 1.5 O2 Board ... 1-16 1.6 Communication Interface Board ... 1-17 1.7 Electrical Wiring Diagram ... 1-19 1.9 Power Supply ... 1-22 1.10 Spirometry (Gas Module SE with Spirometry Only) Overview . 1-24

This Theory of Operation section provides block diagrams, a functional overview of the main components and the gas sampling / measurement principle for the Gas Module. The Gas Module consists of the following main components: • Gas Sampling System • Anesthetic Agent Sensor • O2 Sensor • CPU Board • O2 Board • Communications Interface Board • Power Supply • Spirometry Module (PVX unit) • Water Trap • Internal Tubing

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1-1

Gas Sampling System

1.1

Theory Of Operation

Gas Sampling System The sampling system draws in a patient sample to the analyzers at a fixed rate. The gas sampling system draws patient sample into the module, and removes water and impurities from it in a water trap. The pump draws gas through the sampling line, through the water trap and into the gas measuring units. After the measurements, the gas is expelled through the exhaust port. The sample flow rates are as follows: • For Gas Module II, Gas Module SE, and Gas Module SE with Spirometry, the sample flow rate is 200 ml/min. • For Gas Module 3, the sample flow rate is 200 ml/min with the Adult/Pediatric water trap and 120 ml/min with the Neonatal water trap. A number of flow restrictors are utilized to create a pressure difference with ambient pressure in the gas sensors. A larger pressure difference makes the presentation of the gas concentration curves less sensitive to variations in the airway pressure thus meeting the accuracy requirements. Refer to the FIGURE 1-1 and FIGURE 1-2 for the Gas Tubing Layout and Gas Sampling Component Block Diagram for Gas Module II, Gas Module SE, and Gas Module SE with Spirometry. Refer to the FIGURE 1-3 for the combination Gas Tubing Layout and Gas Sampling Component Block Diagram for Gas Module 3. CO2 absorber Nafion tube

Pneumatic unit G

P OUT

OM unit

REF

F

Water trap

IN

E D C B A

Pressure transducers

Nafion tube

B1

Connection block

B2

TPX unit OUT

IN

IN OUT Damping chamber Sampling pump

FIGURE 1-1 Gas Tubing Layout – Gas Module II, Gas Module SE, and Gas Module SE with Spirometry

1-2

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Theory Of Operation

Gas Sampling System

Room air

Reference gas

Filter

Filter Absorber

Zero valve

Room air Occlusion valve

TPX Pressure Transducer p

Sample line

OM Pressure Transducer dpp

Pump

FIGURE 1-2 Gas Sampling Component Block Diagram – Gas Module II, Gas Module SE, and Gas Module SE with Spirometry Servomex O2 Sensor

AION™ Gas Measurement Bench

Purge Valve

Pump Module

to O2 Sensor

from O2 Sensor to EVAC

DRYLINE™ Water Trap Sample Zero Valve

Pneumatic Module

Purge

Sample In Patient

EVAC Outlet Connection

FIGURE 1-3 Combination Gas Tubing Layout and Gas Sampling Component Block Diagram – Gas Module 3

1.1.1

Water Trap The sample is drawn through a sample line. Then gas enters the monitor through the water trap, where it is divided into two flows, a main flow and a side flow. The main flow goes into the analyzers. This flow is separated from the patient side by a hydrophobic filter. The side flow creates a slight subatmospheric pressure within the water trap which causes fluid removed by the hydrophobic filter to collect in the bottle. The Gas Module 3 uses the DRYLINE™ water trap system.

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1-3

Gas Sampling System

1.1.2

Theory Of Operation

Zero Valve and Absorber The main flow passes through a magnetic valve before proceeding to the analyzers. This valve is activated to establish the zero points for the Anesthetic Agent and O2 Sensors. When the valve is activated, room air is drawn through the absorber into the internal system and the gas sensors. Paralyme is used as the absorbent. The Absorber is for Gas Module II, Gas Module SE, and Gas Module SE with Spirometry.

1.1.3

Nafion™ Tube * A nafion tube is used between the water trap and the zero valve to balance the sample gas humidity with that of ambient air. The tube will prevent errors caused by the effect of water vapor on gas partial pressure when the humid gases are measured after calibration with dry gases. *Nafion is a trademark of Perma Pure Inc.

1.1.4

Gas Analyzers After the zero valve and nafion tube the gas passes through the Anesthetic Agent and O2 Sensors. The oxygen sensor has two inputs. One input accepts the gas sample and the other draws room air for reference. The gas sample finally exits through the exhaust port on the rear of the unit. Refer to sections 1.2 and 1.3 for more information on the Anesthetic Agent and O2 Sensors. The Gas Module 3 uses an AION™ multigas analyzer and a Servomex Paramagnetic Oxygen Sensor. The AION™ multigas analyzer and Servomex Paramagnetic Oxygen Sensor must be a matched pair.

1.1.5

Sample Flow Differential Pressure Transducer The sample flow differential pressure transducer (Gas Module II, Gas Module SE, and Gas Module SE with Spirometry) measures pressure drop across the O2 Sensor inlet restrictor and calculates sample flow from the pressure difference.

1.1.6

Working Pressure Transducer The working pressure transducer (Gas Module II, Gas Module SE, and Gas Module SE with Spirometry) measures absolute working pressure between the Anesthetic Agent and O2 Sensors. It is used to detect situations which will post messages for occlusion and replace trap.

1.1.7

Pneumatic Unit The pneumatic unit contains the zeroing valve, occlusion valve and tubing connections. There is a series of restrictors and chambers forming a pneumatic filter to prevent pressure oscillations in the pump from reaching the measuring units. Zeroing and occlusion valve connections to room air include a dust filter.

1.1.8

Connection Block The connection block contains a sample gas outlet connector and an O2 Sensor reference gas inlet. The inlet is equipped with a dust filter.

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Theory Of Operation

1.1.9

Gas Sampling System

Occlusion Valve The valve (Gas Module II, Gas Module SE, and Gas Module SE with Spirometry) is activated when the sample line gets occluded. The main flow is diverted to the side flow of the water trap to help remove the occlusion faster.

1.1.10

Sampling Pump and Damping Chamber The Gas Module II, Gas Module SE, and Gas Module SE with Spirometry gas sampling pump is a membrane pump that is run by a brushless DC motor. The gas flow rate is measured with a sample flow differential pressure transducer across a known restriction. The motor is automatically controlled to maintain a constant flow, even when the water trap ages and starts to get occluded. It also enables use of sample tubes with varying lengths and diameters. The damping chamber is used to even out the pulsating flow and silence the exhaust flow. The Gas Module 3 pump module is a low power, high reliability membrane pump and flow controller including preamplifier and pump power driver. NOTE:

Gas Module Service Manual Addendum

Flow is never reversed towards the patient.

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Anesthetic Agent Sensor

Theory Of Operation

1.2

Anesthetic Agent Sensor

1.2.1

Gas Module II, Gas Module SE, and Gas Module SE with Spirometry

FIGURE 1-4 Gas Module II, Gas Module SE, and Gas Module SE with Spirometry Anesthetic Agent Sensor The Anesthetic Agent Sensor is a sidestream gas analyzer, measuring real time concentrations of CO2, N2O and five anesthetic agents (Halothane, Enflurane, Isoflurane, Desflurane, and Sevoflurane). The Anesthetic Agent Sensor 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 IR lamp is a 4W filament, surrounded by thermal isolation. There is a hole in the isolation, passing the radiated light to a conical measuring chamber with a 4 mm length.

Temp sensor Sample chamber

Thermopile detectors

Sample Sample gas out gas in FIGURE 1-5 Anesthetic Agent Sensor Principle From the sample chamber, radiated light goes into seven tubular light guides with reflective inner surfaces. At the other end of each light guide there is a thermopile infrared radiation detector with an optical filter in front of it. The Temp sensor measures the Anesthetic Agent Sensor’s temperature and uses it for temperature compensation.

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Theory Of Operation

Anesthetic Agent Sensor

Anesthetic agents or mixtures of two anesthetic agents are automatically identified and concentrations of the identified agents are measured. The Anesthetic Agent Sensor also detects mixtures of more than two agents.

FIGURE 1-6 Infrared Absorbance of N2O and CO2 Concentrations of CO2 and N2O are calculated from the absorption measured at 3 to 5 μm.

FIGURE 1-7 Infrared Absorbance of Anesthetic Agents Identification of anesthetic agents and calculation of their concentrations is performed by measuring absorptions at five wavelengths in the 8 to 9 μm band and solving for the concentrations from a set of five equations. The measuring accuracy is achieved utilizing numerous software compensations. The compensation parameters are determined individually for each Anesthetic Agent Sensor during factory calibration.

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1-7

Anesthetic Agent Sensor

1.2.2

Theory Of Operation

Gas Module 3

FIGURE 1-8 Gas Module 3

FIGURE 1-9 Gas Module 3 Anesthetic Agent Sensor The Anesthetic Agent Sensor is a sidestream gas analyzer, measuring real time concentrations of CO2, N2O and five anesthetic agents (Halothane, Enflurane, Isoflurane, Desflurane, and Sevoflurane). The Anesthetic Agent Sensor is a non-dispersive infrared analyzer, measuring absorption of the gas sample at up to eight infrared wavelengths, which are selected using optical narrow band filters. Anesthetic agents or mixtures of two anesthetic agents are automatically identified and concentrations of the identified agents are measured. The Anesthetic Agent Sensor also detects mixtures of more than two agents.

1-8

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Theory Of Operation

Anesthetic Agent Sensor

The absorption spectra for CO2, N2O, and the five anesthetic agents Halothane, Enflurane, Isoflurane, Sevoflurane, and Desflurane are shown in FIGURE 1-10 and FIGURE 1-11.

Absorbance

N2O

CO2

3.5

4

Wavelength ( μm )

4.5

5

FIGURE 1-10 Infrared Absorption Spectra for N2O and CO2

Desflurane Isoflurane Enflurane

Absorbance

Sevoflurane

Halothane

7

8

9

10

11

12

Wavelength ( μm )

FIGURE 1-11 Infrared Absorption Spectra for Anesthetic Agents To identify seven different gases in a mixture, measurements are done at seven different wavelengths. Measurements are done at an eighth wavelength for reference. The AION™ Multigas Analyzer uses the absorption peaks at 4.2 and 3.9 μm for measuring CO2 and N2O respectively and the absorption peaks in the 8–12 μm range for measuring anesthetic agents. See FIGURE 1-10 and FIGURE 1-11. A set of narrow optical band pass filters intercepts a broadband infrared source to provide these wavelengths. The individual filters are mounted in a rapidly rotating filter wheel that intersects the light path. The filtered light passes into a cylindrical measurement chamber. At the other end of the chamber, there is an infrared radiation detector, whose output is directed to the host interface through the signal processor. See FIGURE 1-12.

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1-9

Anesthetic Agent Sensor

Theory Of Operation

Gas Inlet Gas Outlet Infrared Detector

Light Source

Measurement Chamber

Host Interface

Filter Wheel & Optical FIlters

Signal Processor

FIGURE 1-12 Optical Path No radiation is absorbed if the measurement chamber is empty. The output signal from the detector is at maximum amplitude at a concentration of zero. Lower amplitudes indicate the presence of gases in the measurement chamber. To establish the zero reference, the AION™ Multigas Analyzer occasionally switches the zero valve to direct ambient air through the measurement chamber.

1 - 10

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