LifeSense LS1-9R Operators Manual 2013

CAUTION: Federal law (USA) restricts this device to sale by or on the order of a licensed practitioner. Consult Instructions for Use

®

®

LifeSense is a registered trademark of Nonin Medical AB, a Nonin Medical, Inc. company. Nonin makes no claim for use of the product other than for those uses specified herein and disclaims any liability resulting from other uses. Observe all warnings, cautions, and notes. Unauthorized use, copying, or distribution of this manual is prohibited without written consent from Nonin Medical, Inc. Nonin Medical, Inc. st 13700 1 Avenue North Plymouth, MN 55441-5443 USA +1 (763) 553-9968 (800) 356-8874 (USA and Canada) Fax: +1 (763) 553-7807 E-mail: [email protected] Nonin Medical AB Fibervägen 2 82450 Hudiksvall, Sweden +46 650 401500 (Europe) Fax: +46 650 401514 E-mail: [email protected] www.nonin.com

MPS, Medical Product Service GmbH Borngasse 20 D-35619 Braunfels, Germany References to “Nonin” in this manual shall imply Nonin Medical, Inc. Nonin, Flexi-Form, FlexiWrap, and PureLight are registered trademarks of Nonin Medical, Inc. TrendSense is a Nonin trademark. © 2013 Nonin Medical, Inc. 8830-001-02

Contents Indications for Use ... 1 Contraindications ... 1 Warnings... 1 Cautions... 2 Guide to Symbols ... 5 Introduction ... 6 About LifeSense ... 6 About Capnometry ... 6 About Pulse Oximetry ... 6 Operator Requirements ... 7 Displays and Controls ... 8 Monitor Front View... 8 Monitor Rear View ... 14 Monitor Right Side View ... 15 Using the LifeSense Monitor ... 16 Stationary Operation ... 16 Battery Operation... 16 Mounting ... 17 Pulse Oximeter Sensor ... 17 Intended Use ... 17 Applying the Sensor ... 17 Sample Line ... 18 Intended Use ... 18 Applying the Sample Line ... 18 Nafion Tubing ... 19 Attaching the Nafion Tubing ... 19 Single-Patient Use, Disposable Moisture Trap and Filters ... 19 Replacing the Moisture Trap/Filter ... 19 Trend Screen ... 20 Getting Started... 20 Preparations ... 20 Connect the Patient ... 21 Turn on the Monitor ... 21 Check the Alarm Limits ... 22 Disconnect the Patient ... 22 Settings and Alarms ... 23 Touch Panel Display ... 23 Factory Default Settings ... 23 Alarm Limits ... 24 Pulse Limits ... 24 SpO2 Limits ... 24 Respiration Limits ... 24 EtCO2 Limits ... 24 Changing Settings ... 24 Alarms... 25 Alarm Function ... 25 i

Alarm Silence ... 25 High Priority Alarm ... 26 Low Priority Alarm ... 27 Disable Alarms ... 27 Maintenance and Inspection ... 28 Battery Operation... 28 Charging the Battery ... 28 Checking Battery Capacity... 28 Battery Message ... 28 Battery Care ... 28 Maintenance ... 29 Ensuring Optimal Performance ... 29 Cleaning the Sensor ... 29 Cleaning the Monitor ... 29 Calibration... 29 Calibration Procedure ... 29 Recommended Inspections ... 30 Functional Check ... 30 Yearly Inspection ... 31 Troubleshooting ... 32 Fault Messages ... 32 Troubleshooting ... 33 Accessories ... 34 Monitor Accessories ... 34 Pulse Oximeter Accessories ... 35 Capnography Accessories ... 36 Technical Information ... 37 Operating Environment ... 37 Storage Environment ... 37 Power Requirements ... 37 System Specifications... 38 Pulse Oximeter Specifications ... 39 SpO2 Accuracy Testing ... 39 Capnography Specifications ... 40 Manufacturer’s Declaration ... 41 Pulse Oximeter Response Time ... 45 Service, Support, and Warranty ... 46 Warranty ... 46 Quick Step with LifeSense LS1-9R ... 47

ii

Figures Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6.

Start-up Screens ... 8 Operating Screen ... 10 Trend Screen... 13 Rear View of Monitor ... 14 Right Side of Monitor ... 15 Replacing the Moisture Trap/Filter ... 20

Tables Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7. Table 8. Table 9. Table 10. Table 11. Table 12.

Start-up Screen Icons and Display Descriptions ... 9 Device and Operating Screen Icons and Display Descriptions ... 10 Trend Screen Icons and Display Descriptions ... 13 Rear View Features and Descriptions ... 14 Right Side Components and Descriptions... 15 Factory Default Settings ... 23 High Priority Alarm Parameters and Causes... 26 Low Priority Alarm Parameters and Causes ... 27 Electromagnetic Emissions ... 41 Electromagnetic Immunity ... 42 Guidance and Manufacturer’s Declaration-Electromagnetic Immunity ... 43 Recommended Separation Distances ... 44

iii

Indications for Use The LifeSense® Model LS1-9R Capnography/Pulse Oximeter monitor is indicated for use in simultaneously measuring and displaying functional oxygen saturation of arterial hemoglobin (SpO2), end tidal carbon dioxide (EtCO2), respiration, and pulse rate of well or poorly perfused adult, pediatric, and infant patients. It is intended for use in environments where patients require continuous, non-invasive monitoring of these parameters by a healthcare professional (e.g., hospitals, medical facilities, post-operative care, within facility patient transport, home use, or any Emergency Medical Service (EMS) environments).

Contraindications Do not use LifeSense in an MR environment or in the presence of flammable anesthetics or gases. Do not use LifeSense during defibrillation.

Warnings LifeSense is intended only as an adjunct in patient assessment. It must be used in conjunction with other methods of assessing clinical signs and symptoms. LifeSense is not intended to be used as a primary diagnostic apnea monitor. Never allow liquids to enter into or to be spilled onto the monitor. If liquid has penetrated into the monitor it must be checked by Nonin Technical Service. Accessories marked “single-use” must be used on one patient only and be disposed of after usage. ®

Use only Nonin-branded PureLight pulse oximeter sensors. These sensors are manufactured to meet the accuracy specifications of Nonin pulse oximeters. Using other manufacturers’ sensors can result in improper pulse oximeter performance. Only use power supplies that either are supplied with LifeSense or specified by Nonin (see “Accessories”). When selecting a sensor application site use an extremity without a catheter, blood pressure cuff, or intravascular infusion line. Do not use a damaged sensor. Misuse or improper handling of the pulse oximeter sensor could damage the sensor or the cable, which may lead to inaccurate readings. Never alter or modify the sensor since this may affect the performance or accuracy. If the LifeSense fails to respond as described, discontinue use and contact Nonin Technical Service. Use only Nonin recommended accessories and replacement parts (see “Accessories”). LifeSense displays a BATT LOW message when it has approximately 20 minutes of use remaining before it shuts itself off. EtCO2 value will be diluted when used in combination with supplemental oxygen. To get a true EtCO2 reading it is recommended that the supplemental oxygen is disconnected for a few seconds. Oximeter readings may be affected by the use of an electrosurgical unit (ESU). This device should not be used adjacent to or stacked with other equipment. If adjacent or stacked use is necessary, the device should be observed carefully to verify normal operation.

1

Warnings (Continued) Prior to connecting LifeSense to the power supply and the power outlet, be sure to verify the voltage and frequency rating on the power supply are the same as the power outlet. If this is not the case, do not connect the monitor and power supply to the power outlet. Ensure that all alarm volumes are audible in all situations. Do not cover or obstruct any speaker openings. The use of accessories other than those specified in this manual may result in increased electromagnetic emission and/or decreased immunity of this device. As with all medical equipment, carefully route patient cables and connections to reduce the possibility of entanglement or strangulation. When turning on the monitor, verify that a beep is heard each time a button is pressed. If a beep is not heard, do not use the device. The speaker may not be functioning properly.

Cautions LifeSense should only be operated by trained licensed practitioners. Secure LifeSense with mounting hardware if used in transport vehicles. Do not mount LifeSense directly above the patient. If the monitor is mounted, be sure to check that the adjustable mounting clamp is securely affixed. When mounting the monitor to a mobile pole, mounting the monitor higher than 1.5 meters (5 feet) or mounting more than 2 kilograms (4.5 pounds) of equipment onto the pole may result in tipping, damage to the equipment, or injury. Always turn off the monitor prior to cleaning the monitor or changing the pulse oximeter sensor or moisture trap and/or filter. Portable and mobile RF communications equipment may interfere with medical electrical equipment. The sample line, moisture trap, and filter are single-use disposable components. Do not disassemble the plastic parts of the single-use disposable moisture trap. Dispose all components in accordance with your local, state or national regulations regarding waste management. Ear Clip and Reflectance SpO2 sensors are not recommended for pediatric or infant/neonatal use. The accuracy of these sensors has not been established for pediatric or infant/neonatal use. This equipment complies with IEC 60601-1-2 for electromagnetic compatibility for medical electrical equipment and/or systems. This standard is designed to provide reasonable protection against harmful interference in a typical medical installation. However, because of the proliferation of radiofrequency transmitting equipment and other sources of electrical noise in healthcare and other environments, it is possible that high levels of such interference due to close proximity or strength of a source might disrupt the performance of this device. Medical electrical equipment needs special precautions regarding EMC, and all equipment must be installed and put into service according to the EMC information specified in this manual. Set or adjust alarm parameters one at a time. Do not cover or block speaker opening. This may significantly reduce the sound volume. Inspect the pulse oximeter sensor application site at least every 6 to 8 hours to ensure correct sensor alignment and skin integrity. Patient sensitivity to sensors and/or adhesive strips may vary due to medical status or skin condition. Before each use, it is the operator’s responsibility to verify that the alarm limits are appropriate for the patient being monitored.

2

Cautions (Continued) Always clean the Nonin PureLight reusable sensor after each patient use. Before cleaning, unplug it from the monitor. The patient’s nasal passage may dry out if continuous monitoring is required. Check patient on a regular basis for nasal comfort. If the EtCO2 value is out of normal range (4.4 – 5.7 Vol%/KPa or 33 – 43 mmHG) an internal air leak is possible. Replace the single-use disposable moisture trap and repeat the calibration procedure. If the problem persists, contact Nonin Technical Service. If LifeSense is intended to be stored for longer periods of time, always charge the battery to full capacity before storing it in order to prevent damage to the equipment. Avoid rapid temperature change or extreme temperatures. This can cause malfunction. Never store or transport LifeSense where condensation can occur. However, if this has occurred, wait until all condensation has evaporated before using LifeSense. Do not attempt to replace the battery inside the monitor. The battery is hardwired to the circuit board and cannot be replaced by the operator. Contact Nonin Technical Service when the battery needs replacing. The sample line, moisture trap, Nafion tubing, filter, and T-connector are single-patient use, disposable components. Dispose all components in accordance with your local, state, or national regulations regarding waste management. Do not sterilize or autoclave the monitor or sensors. Do not immerse in liquids. Do not disassemble the plastic parts of the single-use disposable moisture trap. Never open the monitor housing/case. By opening the case you render your warranty invalid. The oximeter sensor might not work on cold extremities due to reduced circulation. Warm or rub the finger to increase circulation, or reposition the sensor. In compliance with the European Directive on Waste Electrical and Electronic Equipment (WEEE) 2002/96/EC, do not dispose of this product as unsorted municipal waste. This device contains WEEE materials; please contact your distributor regarding take-back or recycling of the device. If you are unsure how to reach your distributor, please call Nonin for your distributor’s contact information. This device is designed to determine the percentage of arterial oxygen saturation of functional hemoglobin. Factors that may degrade pulse oximeter performance or affect the accuracy of the measurement include the following: excessive ambient light • • excessive motion • electrosurgical interference • blood flow restrictors (arterial catheters, blood pressure cuffs, infusion lines, etc.) • moisture in the sensor • improperly applied sensor • incorrect sensor type • inadequate signal • venous pulsations • anemia or low hemoglobin concentrations • cardiogreen and other intravascular dyes • carboxyhemoglobin • methemoglobin • dysfunctional hemoglobin • artificial nails or fingernail polish

3

Cautions (Continued) Each time the system is turned on, all audible alarms are disabled for 2 minutes unless the operator presses the Audible Alarm Pause/Resume button. Capnography alarms are not active until the first breath is detected. Oximetry alarms are not active until the first pulse is detected. A functional tester cannot be used to assess the accuracy of a pulse oximeter module or sensor. Be careful not to drop LifeSense on the floor or strike it against hard surfaces. If such an incident happens, do not use LifeSense until a functional test has been carried out. All parts and accessories connected to the serial port of this device must be certified according to at least IEC Standard EN 60950 or UL 1950 for data-processing equipment. The monitor is equipped with automatic barometric pressure compensation. End tidal pCO2 values displayed are calculated based on an atmospheric pressure of 760 mmHg and pH2O of 47 mmHg (example: 760 – 47 = 713, 713 x 5% = 36 mmHg). Water or other liquid in the sampling tube may cause erroneous CO2 readings. Ensure that all connections are tight, leak-free, and properly attached. If the Nafion tubing becomes contaminated or damaged during use, discard it and replace it with a new one. Radios and cell phones or similar devices may affect the LifeSense and should be kept at least 2.5 meters (8 feet) away from the device. Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and land mobile radios, amateur radio, AM and FM radio broadcast towers and TV broadcast towers may affect accuracy.

4

Guide to Symbols This table describes the symbols found on the LifeSense monitor and in this manual. Symbol

Meaning CAUTION! Consult Instructions for Use Follow Instructions for Use CE Marking indicating conformance to EC Directive No. 93/42/EEC concerning medical devices. Authorized representative in the European Community. Type BF-Applied Part Indicates separate collection for electrical and electronic equipment (WEEE). Model/article number Serial number

IPX2

Protected against vertically falling water drops when enclosure is tilted up to 15 degrees per IEC 60529. UL Mark for Canada and the United States with respect to electric shock, fire, and mechanical hazards only in accordance with UL 60601-1 and CAN/CSA C22.2 No. 601.1. ON/OFF Audible Alarm Pause/Resume Charging indicator. This indicator is green when the monitor is connected to a power outlet. DC input. Used for connecting the power supply.

lOlOl

Serial interface for use with either TrendSense™ data memory module or NC1, Nurse Call Accessory.

NONIN SpO2 Input used for connecting a Nonin-branded PureLight SpO2 sensor. Indoor use only Class II, double insulated Date of manufacture

5

Introduction About LifeSense LifeSense allows healthcare professionals to non-invasively monitor pulse oximetry and capnometry on either intubated or spontaneously breathing patients. This very useful combination serves as a reliable indication of the patient’s respiratory and ventilation status. When measuring EtCO2, the patient is attached to the monitor by a sample line that can be an airway adapter for an endotracheal tube, a nasal cannula, or a nasal cannula with supplemental oxygen delivery. A variety of sample lines can be used and connected to a specially designed moisture trap, which is easily snapped into the slot on the left side of the monitor. The sampling lines or cannulas can be used with or without Nafion® tubing. Pulse rate and SpO2 are measured by a Nonin-branded PureLight® finger clip sensor, provided with the system. Use only those accessories and replacement parts recommended by Nonin. Refer to the “Accessories” section for more information. LifeSense has visual and audible alarms when limit readings are outside the predefined limits. Limits can easily be adjusted using the touch panel display. The operator can pause or resume the alarm by pressing the Audible Alarm Pause/Resume button. LifeSense has a touch panel display where settings and adjustments are made. The touch panel display also shows battery status and fault messages. The only buttons on the monitor, ON/OFF and Audible Alarm Pause/Resume, are located on the upper right corner of the front panel. Next to these buttons there is a small indicator that turns green when the monitor is connected to a power outlet. LifeSense operates on battery power for approximately 8 hours.

About Capnometry The monitor uses sidestream non-dispersive infrared (NDIR) spectroscopy to continuously measure the amount of carbon dioxide (CO2) during every breath, the amount of CO2 present at the end of exhalation (EtCO2), and respiratory rate (RR). Capnometry has been proven to be a reliable method for detecting esophageal intubation, hypoventilation, and disengagement of the endotracheal tube during mechanical ventilation. CAUTION: When using sample lines that also deliver oxygen to the patient, it is important to be aware that the EtCO2 value will be diluted when used in combination with supplemental oxygen. To obtain a true EtCO2 reading, it is recommended that the supplemental oxygen be disconnected for a few seconds.

About Pulse Oximetry Pulse oximetry is a non-invasive method that passes red and infrared light through perfused tissue and detects the fluctuating signals caused by arterial pulses. Well-oxygenated blood is bright red, while poorly oxygenated blood is dark red. The pulse oximeter determines functional oxygen saturation of arterial hemoglobin (SpO2) from this color difference by measuring the ratio of absorbed red and infrared light as the volume fluctuates with each pulse.

6

Operator Requirements The LifeSense monitor is easy to operate. Each operator should read this manual before using the monitor. LifeSense should only be operated by licensed practitioners.

7

Displays and Controls A standard LifeSense set-up consists of a monitor, single-use disposable moisture trap with filters, Nonin-branded PureLight finger clip sensor (Model 8000AA), nasal cannula, and power supply. See “Accessories” for information on optional accessories. All operator settings are adjusted using the touch panel display on the monitor.

Monitor Front View When the monitor is turned on, it displays the start-up screens (figure 1 and table 1) and then the operating (figure 2 and table 2) and trend (figure 3 and table 3) screens. The following section describes the icons on these screens as well as their functions.

2

1

4

3

6

5

Figure 1. Start-up Screens

8

Table 1. No.

Start-up Screen Icons and Display Descriptions

Name

Description

1.

Audible Alarm Disable

Pressing this icon turns the audible alarms off. It disables the audible alarms by setting all lower limits to 0.

2.

Audible Alarm Enable

Pressing this icon turns the audible alarms on. Default if no icon is chosen.

3.

≤30kg/66lbs

Pressing this icon selects the default alarm limits for patients weighing 30 kg (66 lbs) or less. Only available if Audible Alarm Enable icon is chosen on previous screen.

4.

>30kg/66lbs

Pressing this icon selects the default alarm limits for patients weighing more than 30 kg (66 lbs). Only available if Audible Alarm Enable icon is chosen on previous screen.

5.

LifeSense Version

Shows LifeSense version. If an error occurs during start-up, an error number displays here and an alarm activates.

6.

Software Revision Level

Shows the software revision level installed on the LifeSense monitor.

SW: REV

9

3 2

1

4

5

6 9 10

7 8

12

11

13

15

14

16

17 18 Figure 2. Operating Screen

Table 2. No.

10

Device and Operating Screen Icons and Display Descriptions

Name

Description

1.

LCD Display

The LCD monitor displays parameters, graphs, menus, and other information. It is also a touch panel from which all the operator-defined settings are made.

2.

Limit Settings

The upper figures represent the highest value set by the operator. The lower figures represent the lowest value set. When the parameter readings fall between the low and high settings, they are treated as normal values. Values outside these limits activate both audible and visual alarms. The limit that triggered the alarm flashes on the display.

3.

Up/Down Bar

Control buttons for increasing or decreasing an alarm limit.

4.

Charge Indicator

This indicator is green whenever the power supply is connected and the battery is charging.

No.

Name

Description

5.

Audible Alarm Pause/Resume

Audible alarms alert the operator when readings are outside the preset limits. The operator can temporarily disable one or more active audible alarms by pressing this button. The audible alarms will remain inactive until one of the following occurs: • 2 minutes elapses. • Operator presses the Audible Alarm Pause/Resume button again. • New SpO2, capnography, or system audible alarm begins (see “Alarm Silence” section). If there are no active audible alarms, pushing this button temporarily disables all audible alarms for 2 minutes, unless the operator presses the button again. This button does not disable the visual alarms. The current alarm status displays on the LCD (see #13 below).

6.

ON/OFF

This button turns the monitor ON or OFF. Press the button for more than 1 second to turn the monitor off. Briefly pressing this button will also enable or disable the audible pulse beep function. NOTE: When enabled, the audible pulse beep (tone) increases as the pulse rate increases or decreases as the pulse rate decreases. The default setting is OFF.

7.

HR

Displays the pulse rate as beats per minute. The pulse rate is updated on the display each second.

8.

SpO2

Displays percent (%) oxygen saturation (%SpO2). The SpO2 value is updated on the display every 1.5 seconds.

9.

ETCO2

Displays the volume of end tidal CO2 in expired air. EtCO2 is shown as mmHg or kPa. The value is updated after each breath without averaging.

10.

RR

Displays the respiratory rate in breaths per minute. The value is the mean of four breaths.

11.

Status Text

Shows alarm messages for the pulse oximeter and battery. See “Alarms” section for more information.

12.

Status Text

Shows alarm messages for the capnometer. See “Alarms” section for more information.

13.

Alarm Symbol

Space for alarm symbol. No symbol means audible alarms are enabled. A bell with broken lines indicates one or more audible alarms are paused. A bell with solid lines indicates that audible alarms are disabled.

14.

Trend Icon

Touch this icon to display the trend screen. The trend screen remains visible until an alarm activates or until the operator touches the screen. NOTE: When an alarm is active, this icon does not display on the monitor and the trend screen cannot be accessed.

11

No.

Name

Description

15.

Pulse Oximetry Plethysmograph

Displays a graph giving information on the oximetry signal (plethysmograph). The signal displays 25 samples per second.

16.

Plethysmograph Scale Displays a scale factor for the plethysmogram. Scale factor will be Factor either /1, /2, /4, or /8 and is automatically set.

17.

Respiration Graph

Displays a graph of the CO2 in expired air (capnograph).

18.

Battery Indicator

Displays the battery status. See “Checking Battery Capacity” for more information.

12

7

1 2

6

3 4

5

Figure 3. Trend Screen

Table 3. No.

Trend Screen Icons and Display Descriptions

Name

Description

1.

Trend HR

Displays a trend graph of the pulse rate. This scale is fixed and cannot be changed.

2.

Trend SpO2

Displays a trend graph of the SpO2 values. This scale is fixed and cannot be changed.

3.

Trend RR

Displays a trend graph of the respiration rate. This scale is fixed and cannot be changed.

4.

Trend ETCO2

Displays a trend graph of the EtCO2 values. This scale is fixed and cannot be changed.

5.

Trend Cursor

A trend cursor points out where the actual sample is in the time interval.

6.

Trend Timescale

Timescale is presented in half-hour segments.

7.

Trend Time

The total trend time is approximately 4 hours of volatile internal memory. Data can be collected using the TrendSense memory module for download to a PC.

13

Monitor Rear View The moisture trap, filter, and equipment label are located on the back of the LifeSense (figure 4). Names and descriptions of each component are listed in table 4.

3 2 1

4

Figure 4. Rear View of Monitor Table 4.

Rear View Features and Descriptions

No.

Name

Description

1.

Single-Use, Disposable Moisture Trap with Filter

The filter is a single-use disposable component and should be replaced after each patient use or cleaning. It fits into the moisture trap and protects the monitor from moisture. The moisture trap clicks into position from the left hand side of the monitor. When the moisture trap is removed, guide marks (numbered 1 and 2) and arrows are visible on the back of the monitor. These guide marks help the user insert the moisture trap. 1. Slide the moisture trap into position. 2. Press it down. Push tab out to remove.

2.

Attachment Holes

Dedicated holes for attaching a mounting bracket. See “Accessories” if a mounting bracket is required. 2 mm screws can be used if there is a need to attach the monitor in a fixed position.

3.

Luer Lock

Luer lock connector for attaching sample line, Nafion tubing, or cannula.

4.

Equipment Label

The label contains the model number, serial number, manufacturing date, manufacturer, UL mark, CE mark, and other applicable symbols. See the “Guide to Symbols” section for descriptions of the different symbols. Every LifeSense device has a unique serial number for identification.

14

Monitor Right Side View Outputs and connections are located on the right hand side of the monitor as shown in figure 5. Names and descriptions of each component are listed in table 5.

1 2 3

Figure 5. Right Side of Monitor Table 5.

Right Side Components and Descriptions

No.

Name

Description

1.

Serial Interface

Serial interface works with either: • TrendSense, to transfer data to a PC. • NC1, Nurse Call Accessory, to add nurse call functionality.

lOlOl 2.

DC Input

Used to connect the power supply to the monitor. Only use Noninspecified power supplies.

3.

SpO2 Connector

Used to connect the PureLight pulse oximeter sensor to the monitor. See “Accessories” for a list of pulse oximeter sensors. No other sensors may be used.

NONIN Sp02

WARNING: Use only Nonin-branded PureLight pulse oximeter sensors. These sensors are manufactured to meet the accuracy specifications of Nonin pulse oximeters. Using other manufacturers’ sensors can result in improper pulse oximeter performance.

15