Inncor Service Manual Issue A Rev 7 Jan 2007

Innovision

Innocor™ Service Manual

TABLE OF CONTENTS 1 1.1 1.2 1.2.1 1.2.2 1.2.3 1.3 1.4 1.5 1.6

INTRODUCTION AND APPLICABILITY OF THIS MANUAL ... 1 APPLICABILITY OF THIS MANUAL ... 1 INTRODUCTION TO INNOCOR ... 1 INTENDED USE ... 1 INTENDED APPLICATIONS AND PATIENT POPULATION ... 2 INTENDED OPERATORS AND ENVIRONMENT ... 2 INNOCOR MODELS... 3 SUMMARY OF REVISION CHANGES ... 3 HARDWARE UPDATES... 3 SOFTWARE CHANGES... 4

2 2.1 2.2 2.3 2.4 2.5 2.5.1 2.5.2 2.5.3 2.5.4 2.5.5 2.5.6 2.5.7 2.6 2.7 2.8 2.8.1 2.8.2 2.8.3 2.8.4

GENERAL DESCRIPTION... 5 OPERATIONAL SPECIFICATION... 5 TECHNICAL SPECIFICATION... 7 CERTIFICATION / SAFETY STANDARDS ... 9 GENERAL BLOCK DIAGRAM... 10 PRINCIPLE OF OPERATION... 12 Principle of CO2, N2O, SF6 measurement... 12 Principle of O2 measurement ... 12 Principle of flow measurement... 13 Principle of pulse and SpO2 measurement... 13 Principle of blood pressure measurement ... 14 Principle of gas filling ... 15 Principle of RVU control... 17 WIRING DIAGRAM... 18 TUBING DIAGRAM... 20 EXTERNAL CONNECTOR CONFIGURATION ... 22 Pulse oximeter ... 22 RVU ... 22 USB... 22 LAN ... 23

3 3.1 3.2 3.3 3.4 3.5 3.6 3.6.1 3.6.2 3.6.3 3.6.4 3.7 3.7.1 3.7.2 3.7.3 3.7.4 3.8 3.8.1 3.8.2 3.8.3 3.8.4 3.8.5 3.9

DETAILED DESCRIPTION OF MODULES ... 24 GAS SAMPLING SYSTEM... 24 CO2, N2O, SF6 MEASUREMENT ... 24 O2 MEASUREMENT... 30 FLOWMETER ... 38 PULSE AND SPO2 MODULE ... 39 BLOOD PRESSURE MODULE ... 41 Description of Operation ... 43 Description of Safety... 43 Calibration... 43 Electronic ... 44 GAS DISTRIBUTION SYSTEM ... 45 Description ... 45 The components in the GDS ... 46 The operational modes ... 47 Specifications, Gas Distribution System ... 49 MAIN INTERFACE BOARD... 51 Power supply ... 52 Valve control ... 53 Sensor Interface... 54 External interfaces / Buzzer... 56 I/F Board electrical Interconnections ... 57 COMPUTER ... 58

January 2007

COR-MAN-0000-002-IN /UK, A/7

i

Innovision

Innocor™ Service Manual

3.9.1 3.9.2 3.9.3 3.9.4 3.9.5

CPU module... 58 4xserial module... 61 LCD ... 61 Touch ... 62 Hard disk... 62

4 4.1 4.1.1 4.1.2 4.1.3 4.1.4 4.2 4.2.1 4.2.2 4.2.3 4.2.4 4.3 4.3.1 4.3.2 4.3.3 4.3.4 4.4 4.4.1 4.4.2 4.5 4.5.1 4.5.2 4.5.3 4.6 4.7 4.7.1 4.7.2 4.8 4.8.1 4.8.2 4.9 4.10 4.11 4.12

MAINTENANCE ... 63 CALIBRATION CONCEPT ... 63 User calibration ... 63 Calibration / check by distributors... 63 Calibration / Check at Innovision ... 64 Enter service mode of Innocor... 64 CALIBRATION OF GAS FILLING FLOW ... 65 Adjustment of low pressure ... 65 Preparation of bolus and air filling calibration... 68 Bolus calibration... 69 Air filling calibration ... 71 GAS CALIBRATION / CHECK... 73 General consideration... 73 O2 calibration ... 73 CO2, SF6 & N2O calibration... 75 SNR test... 76 FLOWMETER CALIBRATION... 78 Flowmeter gain calibration... 78 Calibration of flowmeter linearization table... 79 FLOW-GAS DELAY CALIBRATION... 84 Method ... 84 Setup... 84 Calibration procedure... 85 GAS PRESSURE SENSOR OFFSET CALIBRATION... 86 LEAK TEST ON GAS SUPPLY SYSTEM ... 86 Internal gas supply leak test ... 86 Total gas supply leak test ... 87 EVACUATION TEST ... 88 Automatically detection of bag empty ... 88 Evacuation flow... 88 RVU TEST ... 88 REBREATHING TEST USING A SYRINGE ... 89 CALIBRATION OF TOUCH SCREEN ... 89 CALIBRATION OF NIBP ... 89

5 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11 5.12 5.13

TROUBLESHOOTING ... 90 REBREATHING CURVES... 90 GAS SUPPLY SYSTEM / GAS BOTTLE SYSTEM... 97 REBREATHING MANOEUVRE... 97 GAS SIGNALS... 98 RESULTS ... 99 RVU ... 100 SCREEN / TOUCH ... 100 PGA ... 100 OXIGRAF... 100 PULSE OXIMETER ... 101 NIBP... 101 PRINTER ... 101 SOFTWARE... 102

6

ERROR / WARNING MESSAGES... 103

7

DISASSEMBLY AND REASSEMBLY ... 105

January 2007

COR-MAN-0000-002-IN /UK, A/7

ii

Innovision

Innocor™ Service Manual

7.1 7.1.1 7.1.2 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10

GENERAL SERVICE INFORMATION... 105 Screws for thermoplastics... 105 Flexible tubing... 106 CABINET ... 108 PGA ... 112 OXIGRAF... 114 VALVES ... 116 POWER SUPPLY ... 119 INLET PUMP ... 120 AIR FILL / BAG EVACUATION PUMP ... 121 ACOUSTIC ATTENUATOR... 122 COMPUTER ... 123

8

SPARE PARTS ... 128

January 2007

COR-MAN-0000-002-IN /UK, A/7

iii

Innovision

Innocor™ Service Manual

1

INTRODUCTION AND APPLICABILITY OF THIS MANUAL

1.1

APPLICABILITY OF THIS MANUAL

This service manual provides information required to maintain and repair all models of the Innocor. This manual is applicable for the current production revision. Section 1: Section 1 gives an introduction to the Innocor. Differences between models are summarised in section 1.3. Section 1.4 lists history of this document. Section 1.5 lists the hardware changes made to the Innocor and section 1.6 the software changes. Section 2 gives a general description of the Innocor and its sub-modules. Section 3 gives a more detailed description of the Innocor. Section 4 describes the maintenance of the Innocor. Section 5 gives a troubleshooting for the Innocor. Section 6 lists the error / warning messages given by Innocor. Section 7 describes the disassembly and reassembly of the Innocor. In the following all functions and options of Innocor are described. Some of the functions described or shown may not be available on the device you are using.

1.2

INTRODUCTION TO INNOCOR

1.2.1

INTENDED USE

Innocor is a compact point-of-care device intended to be used for non-invasive measurement of cardiac output and related cardiopulmonary parameters. Cardiac output (CO) is defined as the volume of blood pumped by the heart per unit of time (blood flow in litre per minute). The measurement is non-invasive (i.e. does not necessitate catheterisation or any other penetration through a body orifice or the body surface) in that it is based on a pulmonary gas exchange method called inert gas rebreathing (IGR). The operating principle of Innocor is to let the patient breathe minute quantities of a blood soluble and an insoluble gas in a closed breathing assembly for a short period. The blood flowing through the lungs (effective pulmonary blood flow, PBF) absorbs the blood soluble gas and therefore the disappearance rate is proportional to the blood flow. Other factors affecting the distribution of the blood soluble gas are accounted for by also measuring the blood insoluble gas. The spontaneously breathing patient puts on a nose clip and breathes into a respiratory valve via a mouthpiece and bacterial filter. At the end of expiration the valve is activated so that the patient will breathe in and out (rebreathe) from a rubber bag for a period of 10-20 seconds. The patient is asked to empty the bag during each inspiration and breathe with a slightly increased respiration rate. After this period the patient is switched back to ambient air and the test is terminated. The bag is prefilled with an oxygen (O2) enriched mixture containing two foreign gases; typically 0.5% nitrous oxide (N2O) and 0.1% sulphur hexafluoride (SF6). These gases and CO2 are measured continuously and simultaneously at the mouthpiece by a photoacoustic gas analyser inside Innocor.

January 2007

COR-MAN-0000-002-IN /UK, A/7

1

Innovision

Innocor™ Service Manual

N2O is soluble in blood and is therefore absorbed during the blood’s passage of the lungs at a rate, which is proportional to the blood flow. So, the higher the cardiac output the higher the disappearance rate (slope of measured gas curve). SF6 is insoluble in blood and therefore stays in the gas phase and is used to determine the lung volume from which the soluble gas is removed. The rebreathing test can be performed as a single test at rest or at a given exercise level using e.g. a bicycle ergometer or a treadmill in a stand-alone configuration. Alternatively it can be performed as a part of an exercise protocol where the rebreathing manoeuvres are done at pre-programmed intervals/workloads. By using a pulse oximeter the heart rate (HR) can be measured during the test and used to derive the stroke volume (SV) etc. The arterial oxygen saturation (SpO2) indicates whether the oxygenation is normal and thus if there is a significant intrapulmonary shunt (SpO2 < 95%). An oscillometric non-invasive blood pressure (BP) measuring system is also included as an option. It is designed to take blood pressure measurements including systolic (SYS), diastolic (DIA) and mean arterial pressures (MAP). By combining CO and MAP the systemic vascular resistance (SVR) can be determined. The BBB (Breath-by-Breath) option provides measurements of gas exchange parameters including oxygen uptake, carbon dioxide excretion, ventilation and end-tidal concentrations plus a number of derived parameters. These parameters are determined by simultaneous measurements of the respiratory flow and gas concentrations when breathing ambient air. The respiratory flow is measured by means of a differential pressure type flowmeter (pneumotachometer) placed between the respiratory valve unit and the patient. The gas exchange calculations are carried out online for each breath between the rebreathing tests. This gives the opportunity to perform an incremental exercise test on a bicycle ergometer or treadmill and measure the progress of cardiac function, pulmonary function and gas exchange at the same time. Innocor runs under the Windows XP Embedded operating system on an integrated single-board computer. However, knowledge of Windows is not required to operate the device. The device is operated via a simple touch screen interface. Simply touch/press the buttons on the screen to invoke the desired functions. There is no significant warm-up time required for use of Innocor.

1.2.2

INTENDED APPLICATIONS AND PATIENT POPULATION

Innocor can be used in a variety of medical fields where knowledge of cardiac output and gas exchange is important, e.g. cardiac exercise stress testing, heart failure, cardiac surgery, hypertension, pulmonary hypertension, haemodialysis and pacemaker programming. It can be used both in rest and exercise e.g. with patients who have no symptoms in rest or light exercise. The method involves no risk or pain to the patient. The only requirement is that the patient is capable of understanding the instructions from the operator and performing the manoeuvre well. 1.2.3

INTENDED OPERATORS AND ENVIRONMENT

Unspecialised nurses and paramedics in all parts of the health care system can use Innocor. However, qualified medical personnel should always supervise the user.

January 2007

COR-MAN-0000-002-IN /UK, A/7

2

Innocor™ Service Manual

Innovision

1.3

INNOCOR MODELS

Innocor is produced in different models. An overview of the models is given in the table below. Model Oxygen sensor Blood pressure sensor Breath-by-Breath INN0050 INN0100 √ INN0200 √ INN0300 √ √ INN0400 √ √ INN0500 √ √ √

1.4

SUMMARY OF REVISION CHANGES

A/1 A/2 A/3 A/4

Sept. 2003 Nov. 2003 Feb. 2004 May 2004

A/5 A/6 A/7

Sep. 2004 Mar. 2005 Jan. 2007

1.5

HARDWARE UPDATES

Feb. 2002 Feb. 2002 Nov. 2003 Apr. 2004 May 2005

January 2007

First release Spare parts section added Section “Inert Gas Rebreathing Method” updated “Software User Manual” & “Inert Gas Rebreathing Method” made as separates documents Spare parts list modified Minor updates Breath-by-Breath option included Calibration procedures updated Typical rebreathing curves included

Updated with blood pressure measuring function (NIBP) I/F board updated New gas supply design incl. relief valve New flow pump attenuator New silicone 6 tube New Innocor RVU (replaces the Hans Rudolph valve) Updated with Breath-by-Breath

COR-MAN-0000-002-IN /UK, A/7

3

Innocor™ Service Manual

Innovision

1.6

SOFTWARE CHANGES

5.07 5.06 5.05

01.11.06 22.06.06 22.05.06

5.04

02.05.06

5.03 5.02 5.01 5.00

01.12.05 01.09.05 12.08.05 02.06.05

4.01 4.00

17.12.04 23.09.04

3.02

19.04.04

3.01 3.00 2.02

28.10.03 19.09.03 12.09.03

2.01 2.00

13.03.03 26.11.02

January 2007

Script Support for updating system files (*.ini) Bug in controlling a manual treadmill protocol corrected Faster preparation of rebreathing bag Service interval reminder Native country Updates for the US market Breath-by-Breath updates New Export facilities Support for HR & BP from exercise devices Faster preparation of rebreathing bag Support for variable flow zero calibration interval Printout to Microsoft EMF files (Enhanced Metafile) Support for bolus concentration up to 50% Breath-by-Breath gas exchange calculation Improved regression lines in Data View New symbols Improved exercise protocol Scandisk in case of unauthorized power down Bug in O2-adjust corrected Exercise protocol Calculation of SVRI changed Calculation of SVO2 changed New handling of calculation warnings Standby of gas supply Improved bottle pressure handling Improved script handling Improved service menu Improved handling of databases in case of off-nominal shut down New trend function with support for display of parameters in tables and XY-plots Support for manual entering of HR, SpO2, Load, Speed, Slope Support for User defined parameters Support for calculated parameters based on database values Support for rebreathing bag volume down to 0.5 litre Improved on-line detection to avoid bag opening in the shift from inspiration to expiration. A test is always saved - also in case of errors - in order to display the data to determine the reason for the error. Support for deleting a gas cylinder from the Gas Cylinder list New exit / close down of Innocor New database format (3.02 will automatically convert existing format) Innocor software can run as an offline viewer on a memory key New help pages Support for setting of default printers Innocor software running under Windows XP embedded Estimation of bag volume to 40% of VC Automatic stop after 3 breaths after good mixing Support for beep during rebreathing Support for manual entering of blood pressure New parameters: Vo2/kg & A-V O2 diff. Support for script execution (Copy, Move, Delete etc.) Gas bottle identification implemented Support for different languages implemented

COR-MAN-0000-002-IN /UK, A/7

4

Innovision

Innocor™ Service Manual

2

GENERAL DESCRIPTION

2.1

OPERATIONAL SPECIFICATION

Parameters CO CI SV SI PBF VL HR SpO2 SvO2 A-V O2 diff VO2 VO2/kg Shunt SYS DIA MAP SVR SVRI Hb BSA

Cardiac output Cardiac index * Stroke volume Stroke index * Pulmonary blood flow Lung volume (or FRC, Functional Residual Capacity) Heart rate Arterial oxygen saturation Mixed venous oxygen saturation ** Arterial – mixed venous oxygen saturation ** Oxygen uptake ** Oxygen uptake pr kg ** Intrapulmonary shunt fraction ** Systolic blood pressure ** Diastolic blood pressure ** Mean arterial blood pressure ** Systemic vascular resistance ** Systemic vascular resistance index ** Haemoglobin concentration * Body surface area *

Breath-by-Breath gas exchange parameters: VO2 Oxygen uptake VO2/kg Oxygen uptake pr kg VCO2 Carbon dioxide excretion R Respiratory exchange ratio Ve Expiratory minute ventilation Va Alveolar ventilation Vd Anatomical dead space Vt Tidal volume Resp.Freq. Respiratory rate FO2et End-tidal concentration of oxygen FCO2et End-tidal concentration of carbon dioxide Ve/VO2 Expiratory quotient / ventilatory equivalent for oxygen Ve/VCO2 Expiratory quotient / ventilatory equivalent for carbon dioxide HR Heart rate SpO2 Arterial oxygen saturation Load Exercise level on bicycle ergometer Speed Running speed on treadmill or Pedal speed on bicycle ergometer Slope Slope on treadmill The following parameters can be calculated after an incremental exercise test: AT Anaerobic threshold (measured by V-slope***) RC Respiratory compensation (measured by V-slope***) Rest and max values of all Breath-by-Breath parameters. * ** ***

Requires manual input. Requires optional sensors. Beaver WL, Wassermann K, Whipp BJ (1986) “A new method for detecting anaerobic threshold by gas exchange” J Appl Physiol 60:2020-2027

January 2007

COR-MAN-0000-002-IN /UK, A/7

5

Innovision

Innocor™ Service Manual

Gas analyser Principle:... Photo acoustic Spectroscopy Components and ranges:...N2O 0-2.5%, SF6 0-0.5%, CO2 0-10% Accuracy:...± 1% relative Signal-to-noise ratio: ...> 1000 @ 1% N2O ...> 1000 @ 0.2% SF6 ...> 400 @ 5% CO2 Sampling frequency:... 100 Hz Sample flow rate:... 120 ml/min Rise time (10-90%):...< 250 ms Calibration check interval: ...12 months Oxygen sensor Principle:... Laser diode absorption spectroscopy Measuring range: ... 5-100% Accuracy:...± 1% relative Signal-to-noise ratio: ... > 500 @ 21% O2 Sampling frequency:... 100 Hz Sampling flow rate:... 120 ml/min Rise time (10-90%):...< 250 ms Calibration check interval (2-point):...12 months Calibration (check interval) (1-point): ...1 month Flowmeter Principle: ... Differential pressure Measuring range: ... ±15 l/s Accuracy: ...±2% relative or ±20 ml/s Resolution: ... 1 ml/s Sampling frequency: ... 100 Hz Lowpass filter: ... 18 Hz Offset calibration interval: ...auto Gain calibration interval: ...1 day

January 2007

COR-MAN-0000-002-IN /UK, A/7

6

Innovision

Innocor™ Service Manual

Pulse oximeter Oxygen saturation range:... 0 to 100% Pulse Rate Range: ... 18 to 300 pulses per minute Measurement Wavelengths: Red - 660 nm Infrared - 910 nm ± 2 digits SpO2 accuracy (70 - 100%) (± 1 SD*): Not specified SpO2 accuracy (below 70%): Heart Rate accuracy (No motion, 18-300 BPM): ± 3 digits Heart Rate accuracy (Motion, 40-240 BPM): ± 5 digits Heart Rate accuracy (Low perfusion, 40-240 BPM): ± 3 digits Patient Isolation: Meets 60601-1 Dielectric withstand Leakage Current: Not applicable The pulse oximeter is designed to use Nonin sensors only. *SD (Standard Deviation) is a statistical measure: Up to 32% of the readings may fall outside these limits.

Non-invasive Blood Pressure (NIBP) Method of measurement: ... Oscillometric ...Diastolic values correspond to Phase 5 Korotkoff sounds Blood pressure range: - Systolic:... 40 mmHg to 260 mmHg - Diastolic:... 20 mmHg to 200 mmHg Heart rate range: ...40 BPM to 200 BPM (Beats Per Minute) Transducer accuracy:...± 3 mmHg between 0 mmHg and 300 mmHg

2.2

TECHNICAL SPECIFICATION

Mechanical Size: ... 32 x 26 x 24 cm Weight: ...8-9 kg (depending on options) Electrical Power supply:... 220-240 V ± 10%, 50/60 Hz ... 100-120 V ± 10%, 50/60 Hz Power consumption:...45 W nom., 100 W max. Fuse requirements: ...2 x 1A T/250V Protection: ...Class I type BF according to EN-60601-1 Environmental Operating temperature: ...10 – 40 °C Operating pressure:... 525 – 800 mmHg Operating humidity: ... 10 - 90 % RH, non-condensing @ 30 °C Warm-up time:... 2 minutes Storage temperature: ... -20 to +50º C Storage humidity: ... 0 to 90 % (not condensed) Dust and direct sunlight to be avoided. Display Type: ...Colour TFT LCD display Size: ... 12.1" Resolution: ... SVGA (800x600 pixels) January 2007

COR-MAN-0000-002-IN /UK, A/7

7

Innovision

Innocor™ Service Manual

Touch screen:... High-resolution resistive type Integrated computer Processor: ... 586 class 300 MHz Pentium MMX Hard disk: ... 10 or 20 GB Operating system: ... Windows XP embedded Electrical interfaces Networking: ... 10/100 Mbps Ethernet PC interfaces:... 2 x Universal Serial Bus (USB 1.1) CAUTION: The electrical interfaces on the data interface panel (USB and Network) shall not be used under normal clinical conditions within the patient zone but only during service and occasionally for data exchange. Peripheral equipment connected to these interfaces must be certified according to the respective European standards (e.g. EN 60950 for data processing equipment and EN 60601-1 for medical equipment). Furthermore, all configurations shall comply with the system standard EN 60601-1-1. Everybody who connects additional equipment to the signal input part configures a medical system, and is therefore responsible that the system complies with the requirements of the system standard EN 60601-1-1.

LAN interfaces Speed: ...10 / 100 Mbps Type: ... Ethernet - TCP/IP IP address (default): ...10.0.0.x Workgroup (default):... INNO_WRKGRP Computer name (default): ...“Innocor serial no” Logon from remote computer (access to c:innocordatabases, c:innocorrawdata & c:innocorexport): User access: User Name: ... InnoUser Password:... innopass Super user access (access to all): User Name: ... InnoSuper Password:... superpass Exercise I/F Elmed EGT 1000 ergometer Ergoline VarioBike 550 ergometer Ergoline 800&900 ergometers Ergoline ergoselect ergometers Lode Examiner ergometer Lode Excalibur ergometer Monark 839 ergometer HP Cosmos Series treadmill

January 2007

COR-MAN-0000-002-IN /UK, A/7

8

Innovision

Innocor™ Service Manual

Rebreathing valve Pneumatic operation Disposable bacterial/viral filter for single patient use Hans Rudolph Valve (8200 series): Bag dead space ...13 ml Instrument dead space @ rebreathing (excl. bag dead space) ...102 ml Instrument dead space @ prior to rebreathing ...110 ml Innovision Respiratory Valve without Breath-by-Breath Bag dead space ...13 ml Instrument dead space @ rebreathing (excl. bag dead space & filter)...87 ml Instrument dead space @ prior to rebreathing (excl. filter)...67 ml Innovision Respiratory Valve with Breath-by-Breath Bag dead space ...13 ml Instrument dead space @ rebreathing (excl. bag dead space & filter)...95 ml Instrument dead space @ prior to rebreathing (excl. filter)...75 ml Dead space of BBB port of RVU ...40 ml Filter dead space, PALL (52 ml)...+41 ml Flexible tube ...+56 ml

Gas supply Gas composition:... 5% N2O, 1% SF6, 94% O2 Cylinder capacity: ...18 liters (0.15 l @ 124 bar) Typical number of tests using automatic dilution with air:...75

2.3

CERTIFICATION / SAFETY STANDARDS

93/42/EEC ... Medical Device Directive EN 60601-1 ...General Requirements for Safety EN 60601-1-1 ...Safety Requirements for Medical Electrical Systems EN 60601-1-2 ...Electromagnetic compatibility EN 865: 1997 ... Pulse oximeters - Particular requirements EN 1060-1: 1995 ...Non-invasive sphygmomanometers Part 1: General requirements EN 1060-3: 1997 ...Non-invasive sphygmomanometers Part 3: Supplementary requirements for electromechanical blood pressure measuring systems

January 2007

COR-MAN-0000-002-IN /UK, A/7

9

Innocor™ Service Manual

Innovision

2.4

GENERAL BLOCK DIAGRAM

Innocor General Block Diagram

Option TOUCH SCREEN

CONTROLLER

PULSE OXIMETER PROBE

PULSE OXIMETER (optional)

NIBP CUFF

NIBP (optional)

BBB sensor electronics (optional)

LCD DISPLAY

POWER INPUT MODULE

POWER SUPPLY

HARDDISK

INVERTER

FAN

PC/104

PC/104

QUAD SERIAL PORTS (PC/104)

SENSOR & VALVE CONTROL ELECTRONICS

COM2 /USB

LCD

IDE

ETHERNET

SINGLE BOARD COMPUTER

USB

COM1

analog

RS232 for control (9600 baud)

analog

RS232 (115200 baud)

GAS DISTRIBUTION

analog

GAS CYLINDER

analog signal GAS IN/OUT

Flowmeter (optional)

REBREATHING VALVE

PAS PGA MULTIGAS ANALYSER

O2 SENSOR (optional)

PUMP PULSATION ATTENUATOR

PUMP

GAS OUTLET

Figure 2.4-1 General block diagram. The Innocor consist of the following main parts: • High voltage (Power supply) • An integrated computer • Measuring system • Optional sensors The high voltage part converts the AC input voltage (110/230 V) to DC voltages used by the other subsystems (5 V, ±12 V). The integrated computer consists of the following modules: • Single board computer • Hard disk • LCD display (incl. inverter) • Touch screen (incl. controller) • Quad serial ports (with 4xRS232) The computer controls the measurements of all sensors, and displays the results on the LCD display for the user. The user can operate the software using the touch screen only. The measuring system consists of the following modules: • PGA multigas analyser • Inlet pump (incl. attenuator) • Gas distribution system (incl. gas cylinder)

January 2007

COR-MAN-0000-002-IN /UK, A/7

10

Innocor™ Service Manual

Innovision • Sensor & valve control electronics • Rebreathing valves

The computer controls the PGA via a serial line. All digital and analogue lines are connected to the PGA via the I/F Board (sensor & valve control electronics). The gas distribution system reduces the pressure of the gas in the gas cylinder, and distributes the gas and air to different locations (bag filling of air or bolus, bag evacuation & pneumatic control of respiratory valve). Optional sensors are: • O2 sensor • Pulse oximeter • NIBP • Flowmeter including BBB sensor electronics The O2 sensor gives a measurement of the oxygen concentration and the oxygen consumption. The pulse oximeter sensor gives a measurement of the heart rate and oxygen saturation. The NIBP module is used to measure the blood pressure (diastolic, systolic and mean arterial pressure). The BBB option includes a flowmeter and a BBB sensor electronics for the measurement of inspired / expired flow. The BBB sensor electronics is inserted between the sensor & valve control electronics (IF board) and the PGA. NIBP Main I/F Board

Air filling- and evacuation Computer

O2 sensor PGA Power supply

Touch controller

Patient panel Fan Back light (Inverter)

Figure 2.4-2 Innocor overview – seen from the front.

January 2007

COR-MAN-0000-002-IN /UK, A/7

11

Innocor™ Service Manual

Innovision

Air filling- and evacuation

NIBP

Valves

Main I/F Board

Inlet pump Computer Pulse oximeter LP regulator BBB sensor electronics (not shown)

Attenuator

Power supply Data panel Power panel

PGA

Gas cylinder I/F

Figure 2.4-3 Innocor overview – seen from the back. 2.5

PRINCIPLE OF OPERATION

2.5.1

Principle of CO2, N2O, SF6 measurement

The PGA analyser measures the gas components: CO2, N2O and SF6. It is well known that among the gas species of interest in physiological examinations all except monoatomic gases, noble gases, nitrogen and oxygen absorb specific wavelengths of light in the infrared (IR) spectrum by intermolecular bindings. Therefore in acoustic gas measurements for medical applications Photo acoustic Spectroscopy (PAS) is used to determine all concentrations except for oxygen. When the gas is subjected to intermittent infrared (IR) light of different gasdependent acoustic signals are produced and detected by a microphone. Absorption of light means absorption of energy and causes a heating of the gases/vapours and thereby a rise in pressure. By pulsation of the energy applied to the gas, the rise in pressure will be intermittent, thus causing a pressure fluctuation. By choosing the pulsation frequency in the audible range, the pressure fluctuation becomes an acoustic signal and it is possible to pick up the signal using a microphone. 2.5.2

Principle of O2 measurement

The oxygen analyser is an Oxigraf O2 sensor from Oxigraf Inc. US. The patented Oxigraf sensor uses laser diode absorption spectroscopy in the visible spectrum, similar to the absorption method used to measure CO2, N2O, and SF6 in the infrared spectrum. However, oxygen absorption is in a region of the visible spectrum (760 nm) where there is no interference or absorption by the other gases. Also the emission line width of the laser and the absorption line width of O2 are very narrow, less than 0.01 nm, compared to perhaps 100 nm for January 2007

COR-MAN-0000-002-IN /UK, A/7

12

Innovision

Innocor™ Service Manual

the CO2 absorption band at atmospheric pressure. The spectrally pure laser is thermally tuned precisely to the oxygen absorption line. As the oxygen concentration increases, the light intensity is attenuated. The photo detector response varies linearly with the oxygen concentration. 2.5.3 Principle of flow measurement The flowmeter contains a screen with a pressure output on each side of the screen. By measuring the pressure drop across the screen, the flow can be calculated. 2.5.4

Principle of pulse and SpO2 measurement

Oxygen saturation SpO2, expressed as a percentage, defines the amount of oxygen carried compared to total capacity. It is measured by a two-wavelength pulse oximeter. The SpO2 value is measured by a light absorption technique: Red and infrared light (660 nm and 910 nm) is emitted from the emitter side of the sensor. The light is partly absorbed when it passes through the monitored tissue. The amount of transmitted light is detected in the detector side of the sensor. When the pulsative part of the light signal is examined, the amount of light absorbed by arterial hemoglobins is discovered and the saturation level can be calculated. PATIENT HOOK-UP • • • • •

Connect the sensor to the SpO2 connector on the Innocor side panel. Attach the pulse oximetry sensor to the patient. It is recommended to use the index finger or middle finger. Remove finger nail polish, artificial nails etc. from the measuring site first. For proper sensor positioning, see the instructions for use accompanying each sensor. Do not pull the sensor from its cable.

PRECAUTIONS FOR USE Pulse oximeters are not able to distinguish between HbCO, MetHb and HbO2. The saturation values may be somewhat higher for smokers. Special care should be taken with patients who have burns or carbon monoxide (CO) intoxication. When carbon monoxide intoxication is suspected, always confirm the pulse oximetry reading with a blood sample measurement. Intravascular dyes may cause erroneous readings. For example, methylene blue, indigo carmine, indocyanine green or any substances that contain dyes, interfere with the SpO2 measurement.

January 2007

COR-MAN-0000-002-IN /UK, A/7

13

Innovision 2.5.5

Innocor™ Service Manual

Principle of blood pressure measurement

The non-invasive blood pressure (NIBP) measurement is an option, which may not be installed in your device. It consists of an oscillometric NIBP module with a pressure transducer inside Innocor, a quick coupling on the side panel, a patient cable (air hose) and an arm cuff. The pressure transducer converts the cuff pressure to an analogue output voltage, and also detects the small oscillometric waveforms resulting from the patient's arterial pulses. The oscillometric waveform is passed through a filter network (rejecting artefact and other noise) while being amplified. After digitisation of the oscillometric signal the signal is further filtered (using software filtering techniques) before being used by the main algorithm to determine the systolic and diastolic points in the waveform. Simultaneously, the cuff pressure is measured directly from the transducer output. By combining the information provided by the oscillometric waveform and the cuff pressure, the systolic and diastolic blood pressures are determined. Analysis of the oscillometric waveform also provides information on the pulse rate. PERFORMANCE Blood pressure measurements determined with this device are equivalent to those obtained by a trained observer using the cuff / stethoscope auscultation method, within the limits prescribed by the American National Standard, Electronic or automated sphygmomanometers. The performance with common arrhythmias, such as atrial or ventricular premature beats or atrial fibrillation, has been verified by use of a patient simulator. PATIENT HOOK-UP The operating steps that are important for correct application are described below and include the selection of a suitable cuff size and correct positioning of the cuff. It is important to select the cuff size that is appropriate to the diameter of the patient's upper arm. There are markings on the cuff indicating the limb circumference for which it is appropriate. Use the “RANGE FINDER” on the inside of the cuff to determine the correct size cuff to use. There is a marking of the centre of the bladder, indicating the correct position for the cuff over the artery. Wrap the cuff around the arm making sure that the Artery Marker is aligned over the brachial artery as shown in figure 2.5.5-1. Ensure that the air hose from Innocor to the cuff is not compressed, crimped or damaged. Please, remember that using a cuff that is the wrong size may give false and misleading results.

January 2007

COR-MAN-0000-002-IN /UK, A/7

14

Innovision

Innocor™ Service Manual

Figure 2.5.5-1 Cuff position on patient arm. PRECAUTIONS FOR USE To obtain accurate blood pressure readings, the cuff must be the correct size, and also be correctly fitted to the patient. Incorrect size or incorrect fitting may result in incorrect readings, refer to figure 2.5.5-1 above. Blood pressure readings may also be affected by the position of the patient and his/her physiologic condition and other factors. The NIBP option may not operate correctly, if used or stored outside the relevant temperature and humidity ranges. The nominal range for the result of the blood pressure measurement is: Systolic pressure: 40 to 260 mmHg Diastolic pressure: 20 to 200 mmHg Pulse rate: 40 to 200 BPM 2.5.6

Principle of gas filling

The rebreathing bag is filled prior to a test with an oxygen (O2) enriched mixture containing two foreign gases; typically 0.5% nitrous oxide (N2O) and 0.1% sulphur hexafluoride (SF6). The filling is done in two steps: • •

A bolus part is filled from the gas bottle containing 94% O2, 5% N2O and 1% SF6. The rest is coming from air via an air pump.

Under normal resting conditions it is recommended to use 10% bolus and 90% air, which gives a mixture of: • O2 = 28.3% • N2O = 0.5% • SF6 = 0.1% During exercise (>150 watt) it can be necessary to increase the bolus due to a higher oxygen uptake in order not to have too low oxygen (13%) concentration at the end of the test. The following formulae can be used to manual estimate the max Vo2 during the test:

January 2007

COR-MAN-0000-002-IN /UK, A/7

15

Innocor™ Service Manual

Innovision

Where

Max Vo2 = ((0.2095-0.13)*Vair + (0.94-0.13)*Vbolus) / Time(sec) * 60 Vair = air volume Vbolus = bolus volume Time = rebreathing time

Knowing the Max Vo2 the max work load can be predicted using the formulae: Max load (watt) = (Max Vo2 – 0.3) / 0.01 Examples of using different bag volumes, bolus concentration and rebreathing time: V-bag (l) 1 1.5 1.5 2 2 2.5 2.5 3 3 Bolus (%) 10 10 15 10 15 10 15 10 15 Time (sec) Max Vo2 (l/min) 10 0.9 1.4 1.7 1.8 2.3 2.3 2.8 2.7 3.4 12 0.8 1.1 1.4 1.5 1.9 1.9 2.4 2.3 2.8 14 0.7 1.0 1.2 1.3 1.6 1.6 2.0 2.0 2.4 16 0.6 0.9 1.1 1.1 1.4 1.4 1.8 1.7 2.1 Max load (watt) 10 62 107 140 153 197 199 254 245 310 12 46 84 112 123 159 161 206 199 254 14 35 68 92 101 132 133 173 166 213 16 27 56 76 84 112 113 147 142 183

The pluming diagram for the gas filling is shown in figure 2.5.6-1.

RVU

Rebreathing bag Rebreathing

Evac. Press. gauge Evac./Fill. Pump

P = 0.45 bar One-way valve Pneu 2

Evac.

Air string

LP regul.

P = 2 bar

Airway press. gauge

HP regul.

Zero cal. (PAW)

P < 125 bar

Press. gauge

Pneu 1

Gas analyser assembly

Rebreathing gas cylinder

Exhaust/ suction port

Evacuation line

Gas analyser exhaust port

Figure 2.5.6-1 Gas filling diagram. January 2007

COR-MAN-0000-002-IN /UK, A/7

16