TuffSat Pulse Oximeter User’s Guide and Service Manual March 2005

GE Healthcare

TuffSat® Pulse Oximeter User’s Guide and Service Manual

Oxygen saturation % (SpO2)

Pulse rate in beats per minute

Sensor connector Connect a Datex-Ohmeda sensor (or sensor cable) approved for use with the TuffSat.

Pleth bar Low battery and print icons Flashes on and off when battery power is low.

Segments flash to match pulse rate. Number of flashing segments indicates pulse strength.

Appears when you start printing to the optional printer. For details about printing data, see the appendix: Printer Features and Use.

Backlight button

PIr button

On/off button

Press to display the PIr pulsatile value. Press again to cancel the PIr display.

Press to power on the oximeter. Press again to power it off.

Press to power on the backlight. Press again to power it off.

6050-0006-075 March 2005

Important Rx Only (USA) Attention! Consult the accompanying instructions, including all safety precautions, before using this device.

Responsibility of the manufacturer The safety, reliability, and performance of this device can be assured by the manufacturer only under the following conditions: • Assembly, extensions, readjustments, modifications, and repairs are carried out by authorized personnel. • The device is used in accordance with this manual.

Service and repair Service and repair procedures must be performed by authorized service personnel. Repair this device or its parts only in accordance with instructions provided by the manufacturer. To order replacement parts or for assistance, contact an authorized service office. When shipping the monitor for repair, clean the monitor, allow it to dry completely, and pack it for shipment in the original shipping container, if possible.

Trademarks TuffSat®, OxyTip®, TruTrak®, and PIr® are the property of GE Healthcare Finland Oy. All other product and company names are the property of their respective owners.

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GE Healthcare Finland Oy Helsinki, Finland +358 10 394 11 www.gehealthcare.com © 2005 General Electric Company. All rights reserved.

Contents 1. Overview Product description...1-1 Clinical use ...1-1 Relative Perfusion Index (PIr) pulsatile value...1-2 TruTrak data sampling system...1-2

Theory of operation ...1-2 Signal processing...1-2 Calibration...1-4 Assumptions ...1-4 Methods ...1-4 Circuit board...1-5

Patient and operator safety...1-6 Electrical shock and flammability hazard...1-6 Fire/explosion hazard...1-6 Failure of operation ...1-6 Data validity ...1-6 Operator safety ...1-6 Patient safety and operator safety ...1-6 Patient safety (oximeter)...1-7 Patient safety (sensors) ...1-7 Cleaning...1-7 Maintenance and repair...1-8 Disposal ...1-8

2. Oximeter Features and Use Product information labels ...2-1

Oximeter features and controls ...2-2 PIr pulsatile value display...2-3 Top view ...2-3

Checking normal operation ...2-4 Using the oximeter ...2-5 Data validity and signal strength...2-6 Pleth bar (pulse rate and strength indicator)...2-6

3. Maintenance, Troubleshooting, and Service Oximeter maintenance ...3-1 Replacing oximeter batteries...3-1 Cleaning the oximeter...3-2 Sensors ...3-2

Troubleshooting...3-3 Repair procedures ...3-5 Disassembling the oximeter...3-5 Replacing parts...3-6 Assembling the oximeter ...3-6

Assembly drawing ...3-7 Parts list ...3-8 i

Contents 4. Compliance and Specifications Compliance with standards...4-1 General safety requirements ...4-1 Electromagnetic compatibility (EMC) ...4-2 Electromagnetic effects ...4-2 Software safety checks...4-2

Performance specifications...4-3 General...4-3 SpO2 ...4-3 Interfering substances ...4-3 Sensor emitter wavelength ranges...4-3 Pulse rate...4-3 PIr pulsatile value...4-3 Alarms...4-4 Displays...4-4 Power ...4-4 Low battery indicator (screen icon) ...4-4 Environment ...4-4 Dimensions and weight ...4-4

A. Printer Features and Use Functions and features ...A-1 How the TuffSat stores data...A-1 Printer components ...A-2

Using the printer...A-2 Powering the printer...A-2 Positioning the oximeter and printer...A-3 Printing data ...A-3

Sample printouts ...A-4 Real-time printout and Trend #1 printout ...A-4 Trend #2 printout ...A-5

Troubleshooting...A-5 Printer maintenance...A-6 Replacing printer paper ...A-6 Cleaning the printer ...A-7

Ordering the printer and printer accessories...A-7 Printer specifications ...A-8 Electromagnetic compatibility (EMC) ...A-8 Print indicator (screen icon)...A-8 Power ...A-8 Environment ...A-8 Dimensions...A-8

Warranty

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1. OVERVIEW This chapter contains: • A brief description of the Datex-Ohmeda TuffSat® Pulse Oximeter. • The theory of operation for the oximeter. • A list of the precautions you must take when using this device.

Product description The TuffSat is a small, durable, portable pulse oximeter that operates on battery power. These items are included with the oximeter: • Four 1.5V alkaline AA batteries. • Neoprene carrying case with belt clip. The TuffSat oximeter is capable of printing data through an infrared link to the optional Hewlett-Packard® Infrared Printer (HP 82240B). For information on ordering and using this printer with the TuffSat, see the appendix: Printer Features and Use. Important: Only OxyTip®+ sensors can be used with this monitor.

Clinical use The TuffSat is designed specifically for spot-checking arterial oxygen saturation (SpO2 ) and pulse rate. This easy-to-use oximeter is ideal for use in the environments listed below: • Respiratory care • Subcritical care for hospital satellite locations • Home care • Prehospital/EMS • Rehabilitation • Physician’s office WARNING: Patient safety. The TuffSat oximeter is not intended for continuous monitoring. It has no alarms (audible or visual) and no user-definable parameters.

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Relative Perfusion Index (PIr®) pulsatile value The PIr pulsatile value indicates the strength of the pulse signal at the sensor site: the higher the PIr value, the stronger the pulse signal. A strong pulse signal increases the validity of SpO2 and pulse rate data. PI r is a relative value that varies from patient to patient. Clinicians can use the PIr value to compare the strength of the pulse signal at different sites on a patient in order to locate the best site for the sensor (the site with the strongest pulse signal).

TruTrak® data sampling system The TruTrak data sampling system, patented by Datex-Ohmeda, enables the TuffSat oximeter to calculate SpO 2 many times each second through advanced statistical data processing. While other oximeters calculate only at the peak and trough of each waveform, the TuffSat assesses SpO2 continuously. The TruTrak data sampling system provides reliable readings during times of low perfusion, motion, or electrical interference. The TuffSat oximeter employs an analog/digital (A/D) converter and maximized digital signal processing techniques to produce samples for the TruTrak system to process. The result is a highly reliable level of oximetry performance.

Theory of operation The TuffSat oximeter uses a two-wavelength pulsatile system-red and infrared light-to distinguish between oxygenated (O2 Hb) and reduced (HHb) hemoglobin, each of which absorbs different amounts of light emitted from the oximeter sensor. The SpO2 and pulse rate are determined by the oximeter through sensor signal processing and microprocessor calculations.

Signal processing Sensor LED

Photodetector

Front End Amplifier

Analog Processing

A/D Converter

Digital Processing

Display

Figure 1-1. Signal processing block diagram The sensor contains a light source and a photodetector: • The light source consists of red and infrared light-emitting diodes (LEDs). • The photodetector is an electronic device that produces an electrical current proportional to incident light intensity.

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Overview The two light wavelengths generated by the sensor light source (the red and infrared LEDs) pass through the tissue at the sensor site. The light is partially absorbed and modulated as it passes through the tissue. Arterial blood pulsation at the sensor site modulates transmission of the sensor’s light. Since other fluids and tissues present generally don’t pulsate, they don’t modulate the light passing through that location. The pulsatile portion of the incoming signal is used to detect and isolate the attenuation of light energy due to arterial blood flow. Variable absorption (due to arterial pulse) Arterial blood absorption Venous blood absorption Absorption Other tissue absorption

Time Figure 1-2. Comparative light absorption The sensor’s photodetector collects and converts the light into an electronic signal. Since O2 Hb and HHb allow different amounts of light to reach the photodetector at the selected wavelengths, the electronic signal varies according to which light source is “on” (red or infrared) and the oxygenation of the arterial hemoglobin. The oximeter uses this information to calculate the relative percentage of O2 Hb and HHb. (Red) 660 nm

(Infrared) 940 nm

Extinction (10x)

Wavelength (nm) Figure 1-3. Extinction vs. wavelength graph

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TuffSat User’s Guide and Service Manual The photodetector sends the electronic signal, which contains the light intensity information, to the oximeter. The oximeter’s electronic circuitry processes the electronic signal, calculates the SpO2 and pulse rate values, and displays them on the screen.

Calibration Datex-Ohmeda pulse oximeters use two wavelength ranges, 650 nm to 670 nm and 930 nm to 950 nm, both with an average power of less than 1 mW. These wavelengths are used to calculate the presence of oxyhemoglobin (O 2Hb) and reduced hemoglobin (HHb). A CO-oximeter typically uses four or more wavelengths of light and calculates reduced hemoglobin (HHb), oxyhemoglobin (O 2Hb), carboxyhemoglobin (COHb), and methemoglobin (MetHb). Therefore, pulse oximetry readings and CO-oximetry readings will differ in situations where a patient’s COHb or MetHb are increased. Increased patient COHb leads to falsely increased SpO 2 in all pulse oximeters.

Assumptions The calculation of SpO 2 assumes 1.6% carboxyhemoglobin (COHb), 0.4% methemoglobin (MetHb), and no other pigments. These values are based on the Datex-Ohmeda Pulse Oximeter Empirical Calibration Study. Appreciable variation from these values will influence SpO2 accuracy.

Methods Two different methods of calibration are currently used by manufacturers of pulse oximeters: fractional and functional. Important: The TuffSat pulse oximeter uses the functional calibration method. The user cannot change the calibration method to fractional. Functional saturation is represented mathematically as the percentage of hemoglobin capable of carrying oxygen that is carrying oxygen. O Hb

Functional SpO2 =

O Hb

2 2 x 100 = ( ( HbTOTAL – COHb ) ) x 100 O Hb – MetHb 2 + HHb

The functional calibration is obtained by multiplying the fractional SpO 2 by a value of 1.02.

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Overview

Circuit board The circuit board contains all the circuitry for the TuffSat oximeter. The functions performed by this board are illustrated below.

Power supply

Keys

Power on/off control (reset control)

Backlight LED

Ambient light detection

Alphanumeric LCD and LCD driver

Processor

Infrared (IR) wireless transmitter

Code memory and Data memory

Watchdog timer

Timing

Sensor LED drive

A/D converter

Analog Signal Path

Sensor

Analog front end

Figure 1-4. Circuit board block diagram

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TuffSat User’s Guide and Service Manual

Patient and operator safety Warnings and cautions associated with following safe practices while using the oximeter appear throughout this manual. • WARNINGS indicate potentially harmful situations that may cause injury to a patient or operator. • CAUTIONS indicate conditions that may lead to equipment damage or malfunction. Read this section carefully before using the oximeter to monitor patients.

Electrical shock and flammability hazard Warning : Power off the oximeter before cleaning or servicing.

Fire/explosion hazard Warning : Do not use the monitor in the presence of any flammable anesthetic mixture. Warning : Use only AA batteries in the oximeter.

Failure of operation Warning : It is possible for any device to malfunction; therefore, always verify unusual data by performing a formal patient assessment. Warning : Do not use the oximeter if it fails to function as described or if the validity of data is questionable. Refer to the appropriate sections of this manual to identify and correct the malfunction.

Data validity Warning : To prevent erroneous readings, do not use an inflated blood pressure cuff or arterial blood pressure measurement device on the same limb as the oximeter sensor. Warning : Conditions that may cause inaccurate readings include interfering substances, excessive ambient light, electrical interference, excessive motion, low perfusion, low signal strength, incorrect sensor placement, poor sensor fit, and movement of the sensor on the patient.

Operator safety Warning : Do not handle hot or leaking batteries.

Patient safety and operator safety Warning : To protect against injury and equipment damage from leaking batteries, remove the batteries when the oximeter is not to be used for some time.

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Overview

Patient safety (oximeter) Warning : The TuffSat oximeter is not intended for continuous monitoring. It has no alarms (audible or visual) and no user-definable parameters. Warning : Never test or perform maintenance on the oximeter while using it to monitor a patient. Warning : When the battery becomes depleted, the oximeter shuts off. No alarm sounds. Warning : The correct use of the oximeter is to measure only arterial oxygen saturation (SpO 2), pulse rate, and the Relative Perfusion Index (PI r) pulsatile value. A pulse oximeter does not measure respiration and should never be used as a substitute for an apnea monitor. Warning : This device is not intended for use in a magnetic resonance imaging (MRI) environment.

Patient safety (sensors) Warning : When the display indicates an error condition or the oximeter appears to be operating abnormally, disconnect the sensor immediately. Warning : Patient conditions (such as reddening, blistering, skin discoloration, ischemic skin necrosis, and skin erosion) may warrant changing the site frequently or using a different style of sensor. Warning : Discard a damaged sensor immediately. Do not repair a damaged sensor or use a sensor repaired by others. Warning : To prevent patient injury or equipment damage, use only Datex-Ohmeda sensors approved for use with this oximeter. For complete information about the safe and appropriate use of a sensor, consult the instructions for that sensor.

Cleaning Caution: Follow these guidelines when cleaning the oximeter: • Do not autoclave, pressure sterilize, or gas sterilize the oximeter. • Use cleaning solution sparingly. Do not immerse the oximeter in liquid. Excessive solution can flow into the oximeter and damage internal components. • When cleaning the display lens, do not use abrasive cleaning compounds or other materials that could damage the lens. • Do not use petroleum-based solutions or solutions containing acetone, freon, or harsh solvents. These substances may damage the oximeter and cause a malfunction. Caution: Disposable sensors are intended for single-patient-use only.

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TuffSat User’s Guide and Service Manual

Maintenance and repair Caution: An operator may perform only maintenance procedures specifically described in this manual. Refer servicing to qualified service personnel who are trained in the repair of this equipment. Caution: Internal electronic components are susceptible to damage by electrostatic discharge. To avoid damage when disassembling the oximeter, observe the standard precautions and procedures for handling static-sensitive components.

Disposal Caution: When the oximeter has reached the end of its useful life, dispose of it in accordance with local procedures and regulations.

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2. OXIMETER FEATURES AND USE This chapter contains: • Descriptions of the product information labels that appear on the oximeter. • Descriptions of the oximeter’s features and controls. • Instructions for checking the operation of the oximeter. • Instructions for using the oximeter. • Information to help you determine the validity of the SpO2 and pulse rate values you see on the oximeter.

Product information labels Labels on the TuffSat oximeter provide product information. Agency and regulatory symbols are described in chapter 4. Not for continuous monitoring. SpO2

The TuffSat has no alarms (audible or visual). It is to be used only for spotchecking SpO2 and pulse rate. Manufacturer

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Oximeter features and controls Pleth bar

Oxygen saturation % (SpO2)

The segments pulsate (flash on and off) to match the pulse rate. The number (or height) of lighted segments indicates the pulse strength.

Pulse rate in beats per minute

For more information, see Data validity and signal strength later in this chapter.

Low battery and print icons Flashes on and off until the batteries are replaced or until no power remains. Indicates the battery power is low (10 to 60 minutes for alkaline batteries; not predictable for other battery types).

Backlight button Press to power on the backlight. Press again to power it off.

For more information, see Power in chapter 4. Appears when you start printing to the optional printer.

On/off button

For details about printing data, see the appendix: Printer Features and Use .

Press to power on the oximeter. Press again to power it off.

PII r button

When you stop monitoring, the power is switched off after 5 minutes to conserve battery power.

Press to display the PI r pulsatile value. Press again to cancel the PI r display.

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All patient data are erased from memory when the oximeter is powered off.

Oximeter Features and Use

PIr pulsatile value display

Indicates that the PIr pulsatile value is being displayed.

The PIr pulsatile value. This number represents the relative perfusion (blood flow) at the sensor site.

Top view Important: Only Datex-Ohmeda OxyTip+ sensors can be used with this monitor.

Sensor connector Receptacle for connecting a Datex-Ohmeda sensor (refer to the instructions for the sensor).

Infrared (IR) transmitter port Port through which real-time and trend data are transmitted from the oximeter to the optional printer.

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Checking normal operation Before monitoring a patient, always check that the oximeter is operating normally. WARNING: Patient safety. Never test or perform maintenance on the oximeter while using it to monitor a patient. WARNING: Failure of operation. •

Do not use the oximeter if it fails to function as described or if the validity of data is questionable. Refer to the appropriate sections of this manual to identify and correct the malfunction.

•

It is possible for any device to malfunction; therefore, always verify unusual data by performing a formal patient assessment.

1.

Verify that the four AA batteries are installed. For installation instructions, refer to chapter 3.

2.

Press the on/off button to power on the oximeter. The software version number is displayed briefly in the pulse rate display area. Software version 7.0 is displayed as 070, for example. As the oximeter completes its self-test, verify the following: • The backlight illuminates. • All display elements (including the printer and battery screen icons) illuminate briefly, then all turn off. • The backlight remains on until dashes (–––) are displayed for the SpO 2 and pulse rate values. NOTE: If the low battery icon flashes on and off continuously, change the batteries as instructed in chapter 3.

3.

Place a sensor on your finger and connect the sensor cable to the oximeter.

4.

When the SpO2 and pulse rate values are displayed, verify that the lowest pleth bar segment remains on while one or more of the other segments flash on and off.

5.

Press the PIr button and verify that the PI r pulsatile value is displayed. Press the PI r button again to display the SpO2 and pulse rate.

6.

Disconnect the sensor cable from the oximeter. Verify that dashes are displayed in place of the SpO2 and pulse rate values.

7.

Reconnect the sensor cable to the oximeter. After SpO 2 and pulse rate values are displayed, remove the sensor from your finger and verify that dashes are displayed.

If the oximeter fails to function as described, refer to Troubleshooting in chapter 3.

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Oximeter Features and Use

Using the oximeter WARNING: Patient safety. •

This device is not intended for use in a magnetic resonance imaging (MRI) environment.

•

To prevent patient injury or equipment damage, use only Datex-Ohmeda sensors approved for use with this oximeter. For complete information about the safe and appropriate use of a sensor, consult the instructions for that sensor.

WARNING: Data validity. To prevent erroneous readings, do not use an inflated blood pressure cuff or arterial blood pressure measurement device on the same limb as the oximeter sensor. 1.

Apply the sensor to the patient and connect it to the oximeter. Refer to the instructions for the sensor you are using.

2.

Press the on/off button to power on the oximeter. After completing the brief self-test, the oximeter detects the SpO 2 and pulse rate values and monitoring begins.

3.

Verify that the signal strength is adequate and that the data agree with your clinical evaluation of the patient. See Data validity and signal strength later in this chapter.

If the oximeter fails to function as described, refer to Troubleshooting in chapter 3. WARNING: Patient safety. •

When the display indicates an error condition or the oximeter appears to be operating abnormally, disconnect the sensor immediately.

•

Patient conditions (such as reddening, blistering, skin discoloration, ischemic skin necrosis, and skin erosion) may warrant changing the site frequently or using a different style of sensor.

•

Discard a damaged sensor immediately. Do not repair a damaged sensor or use a sensor repaired by others.

•

When the battery becomes depleted, the oximeter shuts off. No alarm sounds.

WARNING: Data validity. Conditions that may cause inaccurate readings include interfering substances, excessive ambient light, electrical interference, excessive motion, low perfusion, low signal strength, incorrect sensor placement, poor sensor fit, and movement of the sensor on the patient. WARNING: Failure of operation. It is possible for any device to malfunction; therefore, always verify unusual data by performing a formal patient assessment.

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TuffSat User’s Guide and Service Manual

Data validity and signal strength The SpO2 and pulse rate data are continuously calculated as a 12-second “moving” average. Both values are displayed when you begin to monitor a patient, however, their display may be delayed slightly for patients with lower pulse rates. If the displayed pulse rate and the patient’s palpated pulse rate vary significantly, motion artifact or other noise may be affecting the accuracy of the data. A cough or other hemodynamic pressure disturbance can also disrupt the pulse rate. The stability of the SpO 2 readings is a good indicator of signal validity. Motion at the sensor site, low signal strength, incorrect sensor placement, and electrical interference may affect the stability of the readings. To ensure the validity of the signal: • Apply the sensor correctly to the patient (refer to the instructions for the sensor). • Restrict motion at the sensor site or choose a site where motion is less likely. • If possible, remove sources of electrical interference, such as electrosurgical and electrical/electronic devices.

Pleth bar (pulse rate and strength indicator) The pleth bar-a column of seven segments-represents the plethysmographic waveform. During monitoring, the lowest segment is always on; the other segments pulsate (flash on and off). • The rate at which the segments pulsate represents the pulse rate. • The highest segment that pulsates represents the strength of the pulse-as the pulse strength increases, the number of pulsating segments increases. If the pulse strength is low (only the lower four pleth bar segments pulsate), check for the following: • Poor alignment of sensor optical components Make sure the sensor light source and sensor detector are directly opposite each other and that the detector is completely covered by the patient’s skin. If the sensor site is thick, select a site where there is less distance between the light source and the detector. • Low perfusion Change the sensor site or gently massage the site to increase perfusion. • Artificial fingernails or excessive fingernail polish Select a different site or remove the artificial fingernails or polish.

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3. MAINTENANCE, TROUBLESHOOTING, AND SERVICE This chapter contains:

•

Maintenance instructions that include replacing the batteries and cleaning the oximeter.

•

A chart for troubleshooting situations that may occur while using the oximeter.

•

Repair procedures that may be performed by qualified service personnel.

•

An illustration of the oximeter to help you identify its parts and how it is assembled.

•

A list of parts and their order numbers.

Oximeter maintenance WARNING: Electrical shock and flammability hazard. Power off the oximeter before cleaning or servicing. WARNING: Patient safety and operator safety. To protect against injury and equipment damage from leaking batteries, remove the batteries when the oximeter is not to be used for some time.

Replacing oximeter batteries WARNING: Fire/explosion hazard. Use only AA batteries in the oximeter. WARNING: Operator safety. Do not handle hot or leaking batteries. 1.

Power off the oximeter.

2.

Use a flat-blade screwdriver or coin to loosen the screw that secures the battery door to the back case of the oximeter. Remove the door.

3.

Replace the depleted batteries with four new (or recharged) 1.5V AA batteries. Align the + on each battery with the + shown inside the battery compartment.

4.

Position the battery door hinges in the slots on the back case. Close the door and tighten the screw that secures the door to the device.

Dispose of used batteries according to the manufacturer’s instructions or your local regulations.

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