Datex-Ohmeda S-5 M-Modules Technical reference manual

Datex-Ohmeda

S/5™ M-Modules

Technical Reference Manual

Datex-Ohmeda, Inc.

P.O. Box 7550, Madison
WI 53707-7550, USA
Tel. [phone]
Fax [phone]

All specifications are subject to change without notice.

Document No. M1025359

June 2005

GE Healthcare Finland Oy

Helsinki, Finland

P.O. Box 900

FIN-00031 GE, FINLAND

Tel. [phone] Fax [phone]

www.datex-ohmeda.com www.gehealthcare.com

© 2005 Copyright General Electric Company

Responsibility of the manufacturer

GE Healthcare Finland Oy(GE) is responsible for the safety, reliability and performance of the equipment only
if:

− modifications, service and repairs are carried out by personnel authorized by GE.

− the electrical installation 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.

Trademarks

Datex, Ohmeda, S/5, D-lite, D-lite+, Pedi-lite, Pedi-lite+, Mini D-fend, D-fend,
D-fend+, OxyTip+, MemCard, ComWheel, EarSat, FingerSat, FlexSat, PatientO

and Tonometrics are trademarks of GE Healthcare Finland Oy. All other product and company names are

property of their respective owners.

Copyright

© 2005 Copyright General Electric Company

All specifications subject to change without notice.

, Entropy, Patient Spirometry

2

Table of contents

Master Table of Contents

Technical Reference Manual, S/5™ M-Modules

M1025359

For S/5™ Anesthesia Monitor and Critical Care Monitor
and S/5™ Compact Anesthesia Monitor and Compact Critical Care Monitor

Document No. Updated Updated Description

8001008 -6

8001009 –5

8001010 –4

8001011 –4

8001012 –4

8001013 –4

8001014 –4

8001015 –5

8001016 –3

8005426 –1

8001018 –4

8003840 –1

Hemodynamic Modules,
M-NE12STPR, M-NE12STR, M-NE12TPR, M-NESTPR, M-NESTR,
M-NETPR, M-ESTPR, M-ESTR, M-ETPR

Compact Airway Modules, M-CAiOVX, M-CAiOV,M-CAiO, M-COVX,
M-COV, M-CO, M-C

Tonometry Module, M-TONO

EEG Module, M-EEG and EEG Headbox, N-EEG

Cardiac Output Modules, M-COP and M-COPSv

Pressure Module, M-P, Pressure Temp Module, M-PT

Dual Pressure Module, M-PP

NIBP Module, M-NIBP

Recorder Module, M-REC

Oxygen Saturation Modules, M-NSAT, M-OSAT

NeuroMuscular Transmission Module, M-NMT

Anesthesia recordkeeping keyboard for, K-ARKB, Keyboard
Interface Board, B-ARK and ARK Barcode Reader, N-SCAN

1

2

3

4

5

6

7

8

9

10

11

12

8001020 –5

8001021 –4

8005676

8003476-2

8003934-1

8003487-3

8004390

8005571-1

8001005-5

Memory Module, M-MEM

Interface Module, M-INT

Device Interfacing Solution, N-DISxxxx

BIS Module, M-BIS

Remote Controllers, K-REMCO, K-CREMCO

Single-width Airway Module, M-miniC

Entropy Module, M-ENTROPY

PRETSN Module

Airway Modules, G-AiOV, G-AiO, G-AOV, G-AO, Gas Interface Board
B-GAS

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14

15

16

17

18

19

20

21

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Datex-Ohmeda S/5 Modules

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Document No. M1025359

INTRODUCTION

This Technical Reference Manual provides information for the maintenance and service of the
Datex-Ohmeda S/5™ M-Modules, record keeping keyboard, remote controllers and Device
Interfacing System. These Datex-Ohmeda devices are designed for use with S/5™ Anesthesia
Monitor, S/5™ Critical Care Montor, S/5™ Compact Anesthesia Monitor, and S/5™ Compact
Critical Care Monitor.

Please see also the Technical Reference Manual of the S/5 monitor for system specific information
e.g. related documentation, conventions used, symbols on equipment, safety precautions, system
description, system installation, interfacing, functional check and planned maintenance.

For more detailed information about compatibility with different monitor software types and levels
se the "Introduction" chapter of the slot of the module or other device.

Introduction

S/5™ parameter modules, Device Interfacing Solution, Record keeping keyboard and Remote Controller

Document No. M1025359

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Datex-Ohmeda S/5 Modules

Notes to the reader

This Technical Reference Manual is intended for service personnel and engineers who will perform
service and maintenance procedures on the Datex-Ohmeda S/5 Anesthesia Monitor,S/5 Critical
Care Monitor, S/5 Compact Anesthesia Monitor or S/5 Compact Critical Care Monitor.

This Technical Reference Manual completes the Technical Reference Manual of the S/5 Anesthesia
Monitor and S/5 Critical Care Monitor or S/5 Compact Anesthesia Monitor and S/5 Compact
Critical Care Monitor.

• Document number M1025359 is the order number for the whole printed manual. This

manual includes Technical Reference Manual Slots and every slot has own document
number.

• The Technical Reference Manual, S/5 Modules gives detailed descriptions of paramter

modules and other products that can be used with all S/5 modular monitors. Service check
for each product is included in these slots.

For monitor or system specific information see:
The Technical Reference Manual of the S/5 Anesthesia Monitor and S/5 Critical Care Monitor or
The Technical Reference Manual of S/5 Compact Anesthesia Monitor and S/5 Compact Critical
Care Monitor.

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 Finland Oy (GE) assumes no responsibility for the use or reliability of its software in
equipment that is not furnished by GE.

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Document No. M1025359

Introduction

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 bold

D-O Sans (12 pt) typeface, e.g.

Menu Items Menu items are written in bold italic, D-O Sans (11 pt) typeface, e.g. ECG Setup.

‘Messages’ Messages displayed on the screen are enclosed in single quotes, e.g. ‘Please wait’.

Chapters When referring to different chapters in the same manual, the chapter name is written in italic

typeface and is enclosed in double quotes, e.g. chapter “Cleaning and Care.”

Other documents

When referring to different documents, the document name is written in italic typeface, e.g. refer to
User’s Reference Manual.

ECG.

Hypertext links Hypertext links on PDF versions are written in blue color.

WARNING Warnings are written in bold typeface (13 pt), for example:

WARNING Use only hospital-grade electrical outlets and power cord.

CAUTION Cautions are written in the following way (13 pt):

CAUTION The circuit boards contain sensitive integrated circuits that can be damaged by an

electrostatic discharge. Careful handling of the boards is therefore essential.

Document No. M1025359

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Datex-Ohmeda S/5 Modules

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Document No. M1025359

S/5

S/5
S/5

Datex-Ohmeda Hemodynamic modules

TM

NE12STPR Module, M-NE12STPR (rev. 02)

TM

NE12STR Module, M-NE12STR (rev. 02)

TM

NE12TPR Module, M-NE12TPR (rev. 02)

TM

S/5

NESTPR Module, M-NESTPR (rev. 01)

TM

S/5
S/5

S/5

NESTR Module, M-NESTR (rev. 01)

TM

NETPR Module, M-NETPR (rev. 01)

TM

ESTPR Module, M-ESTPR (rev. 04)

TM

S/5
S/5

ESTR Module, M-ESTR (rev. 04)

TM

ETPR Module, M-ETPR (rev. 04)

Technical Reference Manual Slot

Datex-Ohmeda, Inc.

P.O. Box 7550, Madison
WI 53707-7550, USA
Tel. [phone] Fax [phone]

www.us.datex-ohmeda.com

mailto:[e-mail]

All specifications are subject to change without notice.

Document No. 800 1008-6

October 2003

Datex-Ohmeda Division, Instrumentarium Corp.

P.O. Box 900, FIN-00031

DATEX-OHMEDA, FINLAND

Tel. [phone] Fax [phone]

www.datex-ohmeda.com

 Instrumentarium Corp. All rights reserved.

Table of contents

TABLE OF CONTENTS

HEMODYNAMIC MODULES

TABLE OF CONTENTS i

Table of figures iii

Introduction 1

1 Specifications 3

1.1 General specifications ..............................................................................................................................3

1.2 Typical performance .................................................................................................................................3

1.2.1 NIBP................................................................................................................................................3

1.2.2 ECG.................................................................................................................................................4

1.2.3 Pulse oximetry..................................................................................................................................4

1.2.4 Temperature.....................................................................................................................................5

1.2.5 Invasive blood pressure ....................................................................................................................5

1.2.6 Respiration ......................................................................................................................................5

1.3 Technical specifications............................................................................................................................6

1.3.1 NIBP................................................................................................................................................6

1.3.2 ECG.................................................................................................................................................6

1.3.3 Pulse oximetry..................................................................................................................................7

1.3.4 Temperature.....................................................................................................................................7

1.3.5 Invasive blood pressure ....................................................................................................................7

1.3.6 Respiration ......................................................................................................................................7

2 Functional Description 8

2.1 Measurement principle .............................................................................................................................8

2.1.1 NIBP................................................................................................................................................8

2.1.2 ECG.................................................................................................................................................8

2.1.3 Pulse oximetry..................................................................................................................................8

2.1.4 Temperature...................................................................................................................................10

2.1.5 Invasive blood pressure ..................................................................................................................11

2.1.6 Respiration ....................................................................................................................................11

2.2 Main components...................................................................................................................................11

M-ESTPR/-ETPR/-ESTR modules...............................................................................................................11

M-NE12STPR/-NE12STR/-NE12TPR/-NESTPR/-NESTR/-NETPR modules .................................................12

2.2.3 NIBP board ....................................................................................................................................13

2.2.4 ECG board in 3-and 5-lead measurement........................................................................................15

2.2.5 ECG board in 12-lead measurement ...............................................................................................17

2.2.6 ECG filtering...................................................................................................................................19

2.2.7 STP board ......................................................................................................................................20

2.3 Connectors and signals...........................................................................................................................25

2.3.1 Module bus connector....................................................................................................................25

2.3.2 Front panel connectors...................................................................................................................26

2.3.3 Test points on boards .....................................................................................................................27

3 Service Procedures 29

3.1 General service information.....................................................................................................................29

3.2 Service check .........................................................................................................................................29

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3.2.1 Recommended tools......................................................................................................................29

3.2.2 Recommended parts......................................................................................................................29

3.3 Disassembly and reassembly..................................................................................................................40

3.3.1 M-ESTPR, M-ESTR, and M-ETPR modules........................................................................................40

3.3.2 M-NE12STPR/-NE12STR/-NE12TPR/-NESTPR/-NESTR/-NETPR modules.......................................40

3.4 Adjustments and calibrations..................................................................................................................41

3.4.1 Pressure safety level detection “OFFSET”.........................................................................................41

3.4.2 NIBP calibrations ...........................................................................................................................41

3.4.3 Temperature calibration .................................................................................................................43

3.4.4 Invasive pressure calibration ..........................................................................................................43

4 Troubleshooting 45

4.1 Troubleshooting charts ...........................................................................................................................45

4.1.1 NIBP..............................................................................................................................................45

4.1.2 NIBP error code explanation ...........................................................................................................48

4.1.3 ECG...............................................................................................................................................49

4.1.4 Pulse oximetry (SpO

4.1.5 Temperature ..................................................................................................................................50

4.1.6 Invasive blood pressure..................................................................................................................51

4.1.7 Impedance respiration ...................................................................................................................52

4.2 Troubleshooting flowcharts .....................................................................................................................53

4.2.1 M-NE12STPR and M-NESTPR module troubleshooting.....................................................................53

4.2.2 M-ESTPR, M-ESTR, and M-ETPR module troubleshooting .................................................................54

).....................................................................................................................49

2

5Service Menu 55

5.1 NIBP service menu .................................................................................................................................56

5.1.1 NIBP demo menu...........................................................................................................................57

5.1.2 NIBP calibration menu....................................................................................................................58

5.1.3 NIBP safety valve menu..................................................................................................................59

5.1.4 NIBP pulse valve menu...................................................................................................................60

5.1.5 NIBP buttons/leds menu................................................................................................................61

5.1.6 NIBP pneumatics menu..................................................................................................................62

5.1.7 NIBP watchdog menu.....................................................................................................................63

5.2 ECG service menu ..................................................................................................................................64

5.2.1 ECG setup menu ............................................................................................................................66

5.3 STP service menu ...................................................................................................................................67

5.3.1 STP calibration menu .....................................................................................................................69

6 Spare Parts 70

6.1 Spare parts list.......................................................................................................................................70

6.1.1 M-ESTP rev. 01, M-ETP rev. 00, M-EST rev. 00 .................................................................................70

6.1.2 M-NESTPR rev. 00, M-NETPR rev. 00, M-NESTR rev. 00....................................................................74

6.1.3 M-NE12STPR rev. 00, M-NE12STR rev. 00, M-NE12TPR rev. 00.......................................................78

7 Earlier Revisions 81

APPENDIX A 83

Service Check Form 1

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Table of contents

TABLE OF FIGURES

Figure 1 S/5 NE12STPR Module, M-NE12STPR ................................................................................1

Figure 2 Absorption of infrared light in the finger probe parts layout and schematic diagram..............10

Figure 3 Front panel of M-ESTPR.....................................................................................................11

Figure 4 Front panel of M-NESTPR ..................................................................................................12

Figure 5 NIBP board functional block diagram.................................................................................13

Figure 6 3- and 5- lead ECG board block diagram ...........................................................................15

Figure 7 12-lead ECG measurement block diagram.........................................................................17

Figure 8 STP board block diagram...................................................................................................20

Figure 9 Temperature measurement principle .................................................................................21

Figure 10 Pressure measurement principle .......................................................................................21

Figure 11 Pulse oximetry measurement block diagram ......................................................................22

Figure 12 Serial communication and opto isolation of M-NESTPR/-NE12STPR ...................................23

Figure 13 Serial communication and opto isolation of M-ESTPR.........................................................24

Figure 14 Module bus connector (X1) pin layout ................................................................................25

Figure 15 M-NE12STPR and M-NESTPR module troubleshooting flowchart .........................................53

Figure 16 M-ESTPR Module Troubleshooting Flowchart ......................................................................54

Figure 17 Exploded view of M-ESTP Module ......................................................................................70

Figure 18 Exploded view of M-NESTPR Module..................................................................................74

Figure 19 Exploded view of M-NE12STPR Module..............................................................................78

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Document No. 8001008-6

INTRODUCTION

This Technical Reference Manual Slot provides information for the maintenance and service of the
hemodynamic modules. The S/5 M-ESTPR/-ESTR/-ETPR and S/5 M-NE12STPR/-NE12STR/­NE12TPR/-NESTPR/-NESTR/-NETPR are double width modules designed for use with S/5
monitors. Later in this manual modules may be referred to w/o the system name S/5 for simplicity.

Please refer to the Technical Reference Manual of the S/5 monitor for information related to
system e.g. related documentation, conventions used, symbols on equipment, safety precautions,
system description, system installation, interfacing, functional check and planned maintenance.

The M-ESTPR/-ESTR/-ETPR and M-NE12STPR/-NE12STR/-NE12TPR/-NESTPR/-NESTR/-NETPR
modules provide general hemodynamic parameters

S/5 Hemodynamic modules

NOTE: Do not use identical modules in
the same monitor simultaneously.
The following modules are considered
identical:
M-ESTP/-EST/-ETP,
M-ESTPR/-ESTR/-ETPR,
M-NESTPR/-NESTR/-NETPR,
M-NE12STPR/-NE12STR/-NE12TPR

Figure 1 S/5 NE12STPR Module, M-NE12STPR

Table 1 Options of S/5 hemodynamic modules

Parameter NE12STPR NESTPR NE(12)

STR

12

12-lead ECG • (•)(•)

N

NIBP ••••

E

ECG • • •••••

S

Pulse oximetry ••• ••

T

Two temperatures • • •••••

P

Two invasive blood pressures •• •• •

R

Impedance respiration • • •••••

NE(12)
TPR

ESTPR ESTR ETPR

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Datex-Ohmeda S/5 monitors

NOTE: 12-lead ECG measurement requires Display Controller, B-DISP.

NOTE: M-ESTP rev. 01, M-EST rev. 00 and M-ETP rev. 00 work only with S-STD93, S-STD94, S-ARK94, S-STD95, S­ARK95, S-STD96 and S-ARK96 software.

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1 SPECIFICATIONS

1.1 General specifications

Module size 75 × 180 × 112 mm
W × D × H3.0 × 7.1 × 4.4 in
Operation temperature 10 to 40 °C / 50 to 104 °F

@ M-ESTPR/-ETPR/-ESTR

Module weight 0.6 kg / 1.3 lbs
Power consumption 6 W

@ M-NE12STPR/-NE12STR/-NE12TPR/-NESTPR/-NESTR/-NETPR

Module weight 1 kg
Power consumption about 9 W

S/5 Hemodynamic modules

1.2 Typical performance

1.2.1 NIBP

NOTE:Non-invasive blood pressure measurement is intended for patients weighing over 5 kg (11
lb.)

Oscillometric measurement principle.

Measurement range adult 25 to 260 mmHg

Pulse rate range accepted 30 to 250 bpm

Measurement interval 1, 2.5, 3, 5, 10, 15, 30, 60 min (=1h), 2h, 4h

Typical measuring time adult 23 s

Initial inflation pressure adult 185 ±10 mmHg

Venous stasis adult 80 ±10 mmHg / 2 min.

child 25 to 195 mmHg
infant 15 to 145 mmHg

infant 20 s

child 150 ±10 mmHg
infant 120 ±10 mmHg

child 60 ±10 mmHg / 2 min.
infant 40 ±10 mmHg / 1 min.

Cuff widths please see User’s Guide

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Datex-Ohmeda S/5 monitors

1.2.2 ECG

Lead selection, 12-lead ECG I, II, III, aVR, aVL, aVF, V1, V2, V3, V4, V5, V6
Lead selection, oher modules I, II, III, aVR, aVL, aVF, V
Sweep speeds 12.5, 25, 50 mm/sec

DISPLAY FILTER

Diagnostic, 12-lead ECG 0.05 to 150 Hz
Diagnostic, other modules 0.05 to 100 Hz

Monitoring 0.5 to 30 Hz (-3 dB, with 50 Hz reject filter)

ST filter 0.05 to 30 Hz (-3 dB, with 50 Hz reject filter)

HEART RATE FROM ECG

Range 30 to 250 bpm
Accuracy ±5 bpm or ±5 %, whichever is greater
Resolution 1 bpm
Update interval 5 s
Averaging time 10 s

0.5 to 40 Hz (-3 dB, with 60 Hz reject filter)

0.05 to 40 Hz (-3 dB, with 60 Hz reject filter)

ST LEVELS (in main software)

ST level range -9 to +9 mm (-0.9 to +0.9 mV)
Resolution 0.1 mm (0.01 mV)
Averaging calculated from 8 QRS

SYNCHRONIZATION

Direct ECG analog output of ECG, 1 V/1 mV
Pacer 5 V and 0.5 to 2.5 ms pulse, < 30 ms after pacer peak
Defibrillator 5 V and 10 ms pulse, < 35 ms after R-point synchronization

1.2.3 Pulse oximetry

Measurement range 40 to 100 %
Accuracy 100 to 80 %, ±2 digits

(% SpO

Display resolution 1 digit = 1 % of SpO
Display averaging time 20, 10 sec, beat-to-beat
Pulse beep pitch varies with SpO

The monitor is calibrated over the measurement range against functional saturation SpO

PULSE RATE FROM PLETH

Measurement range 30 to 250 bpm
Accuracy 30 to 100, ±5 bpm,

Resolution 1 bpm
Display averaging 10 s

2 ±1 SD)

1

80 to 50 %, ±3 digits
50 to 40 %, unspecified

2

2 level

func.

2

100 to 250, ±5 %

1

1 SD (standard deviation) = 68 % of all readings in the specified range in stable conditions.

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Adjustable pulse beep volume.

PLETH WAVEFORM

Scales 2, 5, 10, 20, 50 mod%, Auto

Start up scale is 20 mod% if AUTO is not selected to be the default setting.

1.2.4 Temperature

Measurement range 10 to 45 °C (50 to 113 °F)
(In rev. ESTP 03/ EST 02/ETP 02 or earlier: 15 to 45 °C (59 to 113 °F))

Measurement accuracy ±0.1 °C (25 to 45.0 °C)

Display resolution 0.1 °C (0.1 °F)
Temperature test automatic (every 10 min)
Probe type compatible with YSI 400 series

1.2.5 Invasive blood pressure

Measurement range -40 to 320 mmHg
Measurement accuracy ±2 mmHg or ±5 %
Zero adjustment range ±150 mmHg
Calibration range ±20 %
Scales upper limit is adjustable between 10 and 300 mmHg in steps of

S/5 Hemodynamic modules

±0.2 °C (10 to 24.9 °C)

10. Lower limit is 10 % of selected upper limit below zero.

Sweep speed 12.5, 25, 50 mm/s

DIGITAL DISPLAY

Range -40 to 320 mmHg
Resolution ±1 mmHg

WAVEFORM DISPLAY

Range -30 to 300 mmHg

PULSE RATE FROM ARTERIAL PRESSURE

Measurement range 30 to 250 bpm
Resolution 1 bpm
Accuracy ±5 bpm or ±5 % whichever is greater

1.2.6 Respiration

NOTE:The respiration measurement is intended for patients over three years old

Measurement range 4 to 120 bpm
Accuracy ±5 bpm or ±5 %
Resolution 1 bpm
Averaging time 30 s
Update interval 10 s

RESPIRATION WAVEFORM

Sweep Speeds 6.25 mm/s and 0.625 mm/s

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Datex-Ohmeda S/5 monitors

1.3 Technical specifications

1.3.1 NIBP

Deflation rate, PR dep. 5 to 13 mmHg/s
Inflation time 20 to 185 mmHg, 1 to 5 s

Automatic software control, max. inflation pressure

Over pressure limit, stops measurement after 2 seconds

The safety valve limits the maximum cuff pressure to 320 mmHg in adult/child mode or 165 mmHg
in infant mode. Independent timing circuit limits pressurizing (>15 mmHg) time to 2 minutes 10
seconds maximum in adult/child mode, and 1 minute 5 seconds in infant mode.

adult 280 ±10 mmHg
child 200 ±10 mmHg
infant 150 ±10 mmHg

adult 320 mmHg
child 220 mmHg
infant 165 mmHg

1.3.2 ECG

Zeroing to ambient pressure is done automatically.

Inflation pressure is adjusted according to the previous systolic pressure, typically 40 mmHg
above. If the systolic pressure is not found, inflation pressure is increased typically 50 mmHg.

Max. measurement time adult 2 min

child 2 min
infant 1 min

Pressure transducer accuracy is better than ±3 mmHg or ±2 % whichever is greater.
Max. error ±4 mmHg.

Protection against electrical
shock Type BF defibrillation proof

Defibrillation protection 5000 V, 360 J
Recovery time 2 s
Input impedance >2.5 MΩ (10 Hz)
CMRR >100 dB (ST)
System noise <40 µV (p-p, RTI)
Allowable offset ±300 mVDC
Gain range 0.2 to 5.0 cm/mV
Pacemaker pulse detection 2 to 500 mV, 0.5 to 2 ms pulses

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Protection against electrical
shock Type CF defibrillator proof

1.3.3 Pulse oximetry

Protection against electrical
shock Type BF defibrillation proof

1.3.4 Temperature

Measurement accuracy ±0.1 °C (25.0 to 45.0 °C)

Protection against electrical
shock Type CF defibrillation proof

NOTE: The accuracy of the measurement may be different from the specified, depending on
transducer/probe used. Please refer to the transducer/probe specification.

1.3.5 Invasive blood pressure

DIGITAL DISPLAY AVERAGING

Digital displays Art and P1 are averaged over 5 seconds and updated at 5 seconds intervals. All
other pressures have respiration artifact rejection.

S/5 Hemodynamic modules

±0.2 °C (10.0 to 24.9 °C)

Accuracy ±5 % or ±2 mmHg, whichever is greater
Transducer and input sensitivity

Input voltage 5VDC
max current 20 mA
Filter 0 to 4 - 22 Hz adjustable
Zero set accuracy ±1 mmHg
Calibration resolution ±1 mmHg
Zero time less than 15 s
Protection against electrical
shock Type CF defibrillation proof

NOTE: The accuracy of the measurement may be different from the specified, depending on
transducer/probe used. Please refer to the transducer/probe specification.

1.3.6 Respiration

Excitation frequency, 12-lead ECG 62.5 kHz

Excitation frequency, other modules 31.25 kHz

Breath detection automatic, range 0.3 to 6 Ω manually adjustable minimum

Input dynamic range 0.2 to 6 Ω
Input impedance range 100 to 5000 Ω
Respiration Rate min. 4 bpm

Lead off detection >3 MΩ

5 µV/V/mmHg

detection: 0.2, 0.4, 0.6, 0.8, 1.0

max. 120 bpm

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Datex-Ohmeda S/5 monitors

2 FUNCTIONAL DESCRIPTION

2.1 Measurement principle

2.1.1 NIBP

NIBP (Non-Invasive Blood Pressure) is an indirect method for measuring blood pressure.

The NIBP measurement is performed according to the oscillometric measuring principle. The cuff is
inflated with a pressure slightly higher than the presumed systolic pressure, and deflated at a
speed based on the patient’s pulse, collecting data from the oscillations caused by the pulsating
artery. Based on these oscillations, values for systolic, mean, and diastolic pressures are
calculated.

The following parts are necessary for the NIBP measurement:

• M-NE12STPR/-NE12STR/-NE12TPR/-NESTPR/-NESTR/-NETPR (or M-NIBP) module

• twin hose (adult or infant model)

• blood pressure cuffs (various sizes)

2.1.2 ECG

Electrocardiography analyzes the electrical activity of the heart by measuring the electrical
potential produced with electrodes placed on the surface of the body.

ECG reflects:

• electrical activity of the heart

• normal/abnormal function of the heart

• effects of anesthesia on heart function

• effects of surgery on heart function

See the User's Guide or theUser's Reference Manual for electrodes positions and other
information.

2.1.3 Pulse oximetry

A pulse oximeter measures the light absorption of blood at two wavelengths, one in the near
infrared (about 900 nm) and the other in the red region (about 660 nm) of the light spectrum.
These wavelengths are emitted by LEDs in the SpO
peripheral tissue and is finally detected by a PIN-diode opposite the LEDs in the probe. The pulse
oximeter derives the oxygen saturation (SpO
between the relative absorption at the two wavelengths and the arterial oxygen saturation SaO

probe, the light is transmitted through

2

) using an empirically determined relationship

2

.

2

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Document No. 8001008-6

In order to measure the arterial saturation accurately, pulse oximeters use the component of light
absorption giving variations synchronous with heart beat as primary information on the arterial
saturation.

S/5 Hemodynamic modules

A general limitation of pulse oximetry is that due to the use of only two wavelengths only two
hemoglobin species can be discriminated by the measurement.

The modern pulse oximeters are empirically calibrated either against fractional saturation

frac;

SaO

2

2

=

2

fracSaO

HbO

2

++

binDyshemogloHbHbO

Formula 1

or against functional saturation SaO

HbO

=

2

funcSaO

Functional saturation is more insensitive to changes of carboxyhemoglobin and methemoglobin
concentrations in blood.

The oxygen saturation percentage SpO
against functional saturation SaO
measurement relative to SaO2func can be maintained even at rather high concentrations of
carboxyhemoglobin in blood. Independent of the calibration method, pulse oximeters are not able
to correctly measure oxygen content of the arterial blood at elevated carboxyhemoglobin or
methemoglobin levels.

Plethysmographic pulse wave

The plethysmographic waveform is derived from the IR signal and reflects the blood pulsation at
the measuring site. Thus the amplitude of the waveform represents the perfusion.

Pulse rate

The pulse rate calculation is done by peak detection of the plethysmographic pulse wave. The
signals are filtered to reduce noise and checked to separate artifacts.

func;

2

2

HbHbO

2

+

measured by the Datex-Ohmeda module is calibrated

2

func. The advantage of this method is that the accuracy of SpO

2

Formula 2

2

Probe

The standard probe is a finger clamp probe which contains the light source LEDs in one half and
the photodiode detector in the other half. Different kinds of probes are available from Datex­Ohmeda.

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Datex-Ohmeda S/5 monitors

Intensity of
transmitted
light

I

max (DC-component)

I

I

min

max

AC-component

Transmitted
light

Incident light

Emitter

RED

Detector

No pulsation

IRED

Pulsatile blood

SpO sensor cable

2

Variable absorption
due to pulse added
volume of arterial
blood

Arterial blood

Venous blood

Tissue

Time

SpO sensor connector

2

6

GND

7

I

LED

4

5

GND

8

V

B

R

C

1

I

S

9

GND

Figure 2 Absorption of infrared light in the finger probe parts layout and schematic

2.1.4 Temperature

The temperature is measured by a probe whose resistance varies when the temperature changes,
called NTC (Negative Temperature Coefficient) resistor.

The resistance can be measured by two complementary methods:

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Document No. 8001008-6

diagram

• Applying a constant voltage across the resistor and measuring the current that flows

through it

• Applying a constant current through the resistor and measuring the voltage that is

generated across it.

In Datex-Ohmeda modules the two methods are combined in the form of a voltage divider. The
NTC-resistor is connected in series with a normal resistor and a constant voltage is applied across
them. The temperature dependent voltage can be detected at the junction of the resistors, thus
producing the temperature signal from the patient. The signal is amplified by analog amplifiers and
further processed by digital electronics.

2.1.5 Invasive blood pressure

To measure invasive blood pressure, a catheter is inserted into an artery or vein. The invasive
pressure setup, consisting of connecting tubing, pressure transducer, an intravenous bag of normal
saline all connected together by stopcocks, is attached to the catheter. The transducer is placed at
the same level with the heart, and is electrically zeroed.

The transducer is a piezo-resistive device that converts the pressure signal to a voltage. The monitor
interprets the voltage signal so that pressure data and pressure waveforms can be displayed.

2.1.6 Respiration

Impedance respiration is measured across the thorax between ECG electrodes. The respiration
signal is made by supplying current between the electrodes and by measuring the differential
current from the electrodes. The signal measured is the impedance change caused by breathing.
From these impedance changes, respiration rate is calculated, and the respiration waveform is
displayed on the screen.

S/5 Hemodynamic modules

2.2 Main components

2.2.1 M-ESTPR/-ETPR/-ESTR modules

T1

T2

ECG+
Resp

Figure 3 Front panel of M-ESTPR

The M-ESTPR, M-ETPR, and M-ESTR modules contain two main PC boards, the STP board and the
ECG board. They work independently. Both of them have their own processor and software EPROM.
Some components on the boards are not used in ETPR and ESTR modules.

SpO

P1

P2

2

ECG

Lead

Start

Wedge

Zero

P1

Zero

P2

In the M-ESTPR module, additionally, there are two small boards, the SP input and the ECG input
boards, attached to the front panel of the module. The front panel has six connectors and four keys.

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Datex-Ohmeda S/5 monitors

The connectors are two for temperature measurement, two for invasive blood pressure
measurement, one for ECG, and one for SpO

measurement. The keys are for ECG lead, Start

2

Wedge, P1 zero, and P2 zero.

In the M-ETPR module, there are two small boards, the ECG input board and the 2P input board
attached to the front panel of the module. The front panel has five connectors and four keys. The
connectors are two for temperature measurement, two for invasive blood pressure measurement,
and one for ECG

measurement. The keys are for ECG lead, Start Wedge, P1 zero, and P2 zero.

In the M-ESTR module, there are two small boards: the S input board and the ECG input board,
attached to the front panel of the module. The front panel has four connectors and one key. The
connectors are two for temperature measurement, one for ECG, and one for SpO
The key is for ECG lead select.

NOTE: M-ESTP rev. 03, M-ETP rev. 02 and M-EST rev. 02 and all earlier revisions have separate T
and SP input boards.

2.2.2 M-NE12STPR/-NE12STR/-NE12TPR/-NESTPR/-NESTR/-NETPR modules

measurement.

2

Auto

On/Off

NIBP

T1

ECG+
Resp

P1

Start

Cancel

P2

T2

Zero

SpO

2

P1

Zero

P2

Figure 4 Front panel of M-NESTPR

The M-NESTPR, M-NETPR, and M-NESTR modules contain three main PC boards, the STP board,
the ECG board, and the NIBP board. They work independently. Each of these has their own
processor and software EPROM.

The M-NE12STPR, M-NE12TPR, and M-NE12STR contain three main PC boards, The STP board,
the ECG board and the NIBP board. They work independently. Each of them has their own
processor. The STP board and NIBP board have software EPROM. In the ECG board the software is
in flash memory. The STP and NIBP boards are the same as in M-NESTPR module but the ECG
board and ECG input board are different.

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Document No. 8001008-6

In the M-NESTPR module, there are two small boards, the SP input and the ECG input board
attached to the front panel of the module. The front panel has seven connectors and four keys. The
connectors are two for temperature measurement, two for invasive blood pressure measurement,
one for ECG, one for NIBP, and one for SpO

measurement. The keys are for NIBP Auto On/Off,

2

NIBP Start/Cancel, P1 zero, and P2 zero. The structure of M-NE12STPR is similar except the ECG
board and ECG input board are different.

In the M-NETPR module, there are two small boards, the 2P input board and the ECG input board,
attached to the front panel of the module. The front panel has six connectors and four keys. The

connectors are two for temperature measurement, two for invasive blood pressure measurement,
one for ECG, and one for NIBP. The keys are for Auto On/Off, Start/Cancel, P1 zero, and P2 zero.
The structure of M-NE12TPR is similar except the ECG board and ECG input board are different.

In the M-NESTR module, there are two small boards, the ECG input board and the S input board,
attached to the front panel of the module. The front panel has five connectors and two keys. The
connectors are two for temperature measurement, and one for SpO
and one for NIBP. The keys are for Auto On/Off, Start/Cancel. The structure of M-NE12STR is
similar except the ECG board and ECG input board are different.

2.2.3 NIBP board

Cuff

Zero

valve

Exhaust

valve 2

Joining chamber

Exhaust valve 1

Check valve

Bleed valve

Pump

S/5 Hemodynamic modules

measurement, one for ECG,

2

Pump

and

valve

M

driver

B1 B2

to/from module bus

X

Pressure
transducers

converter

Power-up

reset

RS485

1

EEPROM

(calibration

Figure 5 NIBP board functional block diagram

Pressure transducers

The NIBP board contains two pressure transducers. They are of piezoresistive type. One is used for
measuring the pressure of the blood pressure cuff and the pressure fluctuations caused by arterial
wall movement (B1). The other is used for detection of cuff hose type, cuff loose and cuff occlusion
situations etc. (B2). The transducers are internally temperature compensated. They are supplied by
a constant voltage and their output voltage changes up to 40 mV max. (50 kPa, 375 mmHg).

AD-

interf.

data)

Write protection switch

Overpressure control

CPU

80C51FA

Internal

watchdog

Address
decoder

Address

latch

Address bus

Watchdog

timer

RAM EPROM

Databus

+15 VD

Front
panel

keys

Software

control

NESTPR_NIBP_board_blck_dgrm .vsd

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Datex-Ohmeda S/5 monitors

Signal processing

Two signals from the pressure transducers are amplified and sent to the A/D converter. After the
converter, digitized signals are sent to the microprocessor for data processing. Before the
converter, one of the signals is used to adjust the offset to the pressure safety level.

The NIBP board is controlled with a 80C51FA microprocessor at 16 MHz oscillator frequency.

Memory

NIBP program memory (EPROM) size is 128k × 8. RAM size is 32k × 8 bit and it stores variable
values of the NIBP measurement. EEPROM is size 64 × 16 bit and is used to store the calibration
values for the pressure transducers, the pulse valve constants gained during measurements, the
PC board identification, and module serial number.

Software control

Software controls valves and pump. In addition to the individual on/off signals for each component
there is a common power switch for the valves and the pump that can be used at pump/valve
failures.

In addition to external RS485 reset line the microprocessor system is equipped with its own power­up reset. See the section in the ECG board’s description: “RS485 communication”

Watchdog timer

The NIBP board is equipped with a software independent safety circuit to disconnect supply
voltages from the pump and the valves if the cuff has been pressurized longer than the preset time.
As soon as the cuff pressure rises over a specified pressure limit, timer starts counting. The timer is
adjusted to stop the pump and open the valves after 2 minutes 10 seconds in adult/child mode
and after 1 minute 5 seconds in infant mode.

Valves

Exhaust valves are used for emptying the cuff and the joining chamber after the measurement.
Exhaust valve 1 is also used as safety valve in infant mode. The valve opens at 165 mmHg. Exhaust
valve 2 is also used as safety valve in adult mode and opens at 320 mmHg.
The bleed valve is used for emptying the cuff during measurement. The zero valve is used for
connecting the pressure transducer B1 to open air.

Power supply section

All connections are established via 25-pin connector (D-type, female). The module needs +5 V,
±15 V, and +15 VD (dirty) power supply to operate. The pump and the valves use separate +15 VD
power line. The supply voltages are generated in the power supply section of the S/5 monitor. The
reference voltages ±5 V

and +10 V

ref

are generated on the NIBP board.

ref

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Document No. 8001008-6

2.2.4 ECG board in 3-and 5-lead measurement

Patient signals are connected to overload protection circuits (resistors and gas-filled surge
arresters) and analog switches to instrumentation amplifiers. Then the signals are amplified by 480
and limited by slew rate. Then they are A/D-converted, analyzed and transferred to module bus in
digital form.

PATIENT

Overload protection

RL F CN

Defibrillation

detector

uP

uP

uP

Slew-rate

detector

HP

filter

Anti­alias

Analog switches

Slew-rate

detector

uP

HP

filter

uP

Anti­alias

uP

uP

Slew-rate

detector

HP

filter

Anti­alias

uP

uP

Slew-rate

detector

HP

filter

Anti­alias

S/5 Hemodynamic modules

Lead selection logic

controlled by ECG lead selection

signals from uP

Resp

amplifier

Sync. Rectifier

31 kHz

from uP

Figure 6 3- and 5- lead ECG board block diagram

Analog ECG section

The ECG cable is connected to connector pins E1 to E6 on the input board which contains an
overload protection circuit. Leads are connected to amplifiers via analog switches. States of the
switches depend on the cable type. Lead-off, noise and pacemaker are detected by a slew rate

ISOLATION

Supply

voltages

Power

source

Power

source

Opto-

coupler

Opto-

coupler

to STP Board

Amplifier

A/D

Micro-

processor

(uP)

Direct

ECG

Direct

ECG

NESTPR_ECG_brd_blck_dgrm.vsd

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Document No. 8001008-6

Datex-Ohmeda S/5 monitors

detector. Lower frequency is determined by high pass (HP) filter 0.5 Hz (monitor bandwidth) or

0.05 Hz (diagnostic or ST- bandwidth).

Respiration section

3-lead cable The analog switches control the current supply source of the impedance respiration measurement,

and the lead selection for the 3-lead cable can be seen from the following table:

Table 2 Lead selection and coding for the 3-lead cable

Selected lead Current source between Signal measured from

IR - L N

II R - N L

III L - N R

Position on

IEC standard coding AAMI standard coding

body surface

right arm R = red RA = white

left arm L = yellow LA = black

left leg F = green LL = red

5-lead cable When the 5-lead cable is used, the current source is between L-F and the signal is measured from

the N, independently on the lead selection.

The respiration amplifier consist of the operational amplifiers, and the components around them.
There is an analog switch for controlling the gain of the first stage of the preamplifier. Synchronous
rectifier consists of the analog switches, which are used for detecting the respiration signal from 31
kHz amplitude modulated raw signal. The amplifier stage consists of the differential amplifier and
the last amplifier. The differential amplifier consists of the operational amplifiers and the
components around them. This stage is AC-coupled on both sides for minimising the offset
voltages. The last amplifier is used for amplifying the signal derived from differential amplifier
stage. The respiration signal is zeroed at the beginning of the measurement. Zeroing is also used
for fast recovering the measurement after the motion artefact. This is done in amplifier section.

NOTE: The respiration measurement is switched OFF for 20 seconds when defibrillation is detected
at the defibrillation detector.

Microprocessor section

Microprocessor contains RAM and EPROM memories. The processor uses external EEPROM
memory. The microprocessor’s internal 8-channel A/D-converter converts the ECG-signals to
digital form. See the section in ECG board’s description: “RS485 communication

Serial communication

Communication with the module bus is made through RXD and TXD pins. See the section in STP
board’s description: “Serial communication”.

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Document No. 8001008-6