Puritan Bennett GoodKnight 425 ST Bilevel Machine


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    Product Overview

    The GoodKnight 425ST BiLevel machine is everything you need to monitor therapy effectiveness and comes with new FlowSens Technology. Designed for both daily use or small enough to travel, the 425ST has a Backup Rate that helps manage breathing. The FlowSens technology, Backup Rate and software are the most complete solution on the market for treating sleep apnea.

    Manufactured by Puritan Bennett.

    Product Features

    This is a BiLevel machine which differs from a CPAP in that it switches back and forth between two pressure levels, one higher and one lower, rather than providing one continuous pressure level. The pressure upon inhalation is higher to hold the airway open, but as the user exhales, the pressure drops to a preset lower level. The GoodKnight 425ST BiLevel comes with FlowSens technology that helps optimize therapy effectiveness through controlled breathing. By allowing CPAP users to set the device's sensitivity, the flow-based detection system compares CPAP user data with a delayed air flow to trigger inhalation and exhalation breaths. The FlowSens technology provide a unique custom device can compensate air flow on a breath-by-breath basis.

    A BiLevel machine responds well to people with very high CPAP pressure needs, weak chest wall muscles, lung disease or other health problems that keep them from being able to exhale against a CPAP pressure. The Puritan Bennett GoodKnight 425ST model comes with a Backup Rate that will initiate a cycling process of exhalation to inhalation if the CPAP user's breathing rate falls below the prescribed ratio.

    • Smallest, lightest Bilevel, BiPAP or VPAP
    • SilverLining software compatible
    • International power supply
    • Direct DC operation
    • Automatic altitude compensation
    • Two washable, reusable pollen filters
    • 2 year manufacturer warranty against defects.

    Specifications

    This Product Includes...

    • GoodKnight 425ST Bilevel Machine
    • 6 Foot Hose
    • Carry Case
    • 2 Reusable Foam Filters
    • All Manuals

    Product Specifications

    Pressure Range 4cm to 25cm H2O

    Ramp Time 0 to 30 min. (5-min. increments)

    Starting Ramp Pressure From 4cm, user-adjustable

    Dimensions 5.6" x 2.9" x 7.7"

    Weight Bilevel: 1.54 lbs.; Power Supply Module (included): 1.16 lbs.; Total weight 2.7 lbs.

    Altitude Compensation Automatic

    Electrical Requirements 100 - 240 AC, 12volt DC

    CPAP.com always offers these services:

    • 8 am to 8 pm CST Toll Free Phone and Email Support
    • 24 hour access to our CPAPtalk.com Support Forum
    • Learning Center for information on sleep apnea and cpap equipment
    • Consumer Purchasing Trends Reports
    • Warranty Services for all items purchased through CPAP.com
    • Insurance Compliant Invoices
    • Free Prescription Request System

    Important Tips

    BiLevel is the generic term to describe these machines. BiPAP is registered with Respironics, ResMed uses VPAP, and Bi-Level is registered with Covidien.

    The 12 volt jack on this machine is not the same size as the 420 series CPAP machines. Use the Respironics "12volt DC Power Cord (to connect CPAP to cigarette lighter socket)" for battery operations. Part # 1001956.

    Error Note: If the machine displays an error 7 or "ER 7" this indicates an issue internally with the machine's blower. You can contact the provider of the machine to seek service if it is available, or the machine may need to be replaced.

    cpaptalk.com 425 Bi-Level Interview

    Manufacturer Warranty
    This machine comes with a 2 Year Manufacturer Warranty. CPAP.com will work with the manufacturer on your behalf if the machine needs repairs. Please follow these steps:

    • Contact us at cpap@cpap.com or 1-800-356-5221 to receive an RMA (Return Merchandise Authorization) Number before returning the equipment
    • Include a note with the machine describing the issue you are experiencing, along with your full contact information to include a return shipping address and the RMA number provided to you
    • Ship only the defective items to CPAP.com at 10101 Stafford Centre Drive, Stafford, TX 77477
    • Do not return accessory items such as the carry bag, hose or power cords
    • Loaner Machines are available for rental during the warranty process
    • Email updates will be sent to keep you informed as the machine moves through the warranty process
    • CPAP.com will contact the manufacturer on your behalf and handle all shipping between us and the manufacturer
    • The repaired or replaced unit will be returned to you. Shipping charges may apply.

    Please note: The manufacturer warranty is voided by water damage or misuse of the machine.



    Power Options

    Universal Power

    This system operates automatically between 110v and 240v AC. When traveling either inside or outside the USA, there are no switches to switch or fuses to change. The machine will automatically sense what voltage is needed and set itself to run on that power.

    The user will need to adapt the plug that goes into the wall to fit the style of outlet socket that is being used. This is simply done with a Power Adapter Plug kit. This is the same type of plug adapter that would be used with a hair dryer or an electric shaver. World Traveler Power Adapter Plugs.

    Universal 12 Volt DC Power Cord

    This machine come equipped with a DC plug on the back of the unit. This allows the user to connect the CPAP to an external DC battery source. The IntelliPAP can be powered by plugging the 12volt DC Power Cord into a cigarette lighter plug. This is ideal for traveling by car, boat, or recreational vehicle that is equipped with a cigarette lighter plug.

    CPAP.com Battery Kit with Universal 12 Volt DC Cable

    The 2.5 lb CPAP.com Battery Pack is surprisingly small and lightweight. The lithium ion battery can be recharged at any discharge level without losing charge time due to battery memory loss. This battery has been approved by the United Nations and Department of Transportation as tested safe for travel. This battery kit comes with the CPAP.com battery and the 12 Volt DC Power Cord.

    Respironics Battery Kit with Universal 12 Volt DC Cable

    This portable battery pack is an external lead acid battery that is the ultimate in power, portability and convenience. This battery kit comes with the Respironics battery and the 12 Volt DC Power Cord (connects CPAP to cigarette lighter socket).

    CPAP Video & FAQ

    Frequently Asked Questions (FAQs)

    What does CPAP therapy do?
    CPAP therapy provides a constant airflow which holds the airway open so that uninterrupted breathing is maintained during sleep. It is traditionally provided through a nasal mask that seals around the nose to maintain the pressure level.
    Which CPAP masks work on which machines?

    Any mask will work with any machine, with one important exception. The ResMed AirMini is only compatible with certain ResMed CPAP masks. Compatible masks for the AirMini are as follows:

    • ResMed AirFit™ N20 Nasal Mask
    • ResMed AirFit™ F20 Full Face
    • ResMed AirTouch™ F20 Full Face
    • ResMed AirFit™ P10 Nasal Pillow

    When considering another CPAP, APAP or BiPAP machine from ResMed or any other manufacturer, mask compatibility extends to all brands. The AirMini uses non-standard tubing to connect the machine to the mask, and is the primary reason why other masks won't work with the AirMini. Despite this issue, many of our customers consider the AirMini to be an excellent machine.

    How do I choose the machine that is right for me?
    We provide our customers with many tools to make informed decisions about their machine purchases. Options include:
    How can I compare different machines?
    We work very hard to provide many different ways for our customers to compare products. Here are the machine product guides we have created and maintain:
    • CPAP Machine Comparison Guide. This guide stacks up every CPAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular CPAPs, or all CPAP machines we sell.

      Compare Most Popular CPAP Machines

      Compare All CPAP Machines

    • Auto Adjusting Machine (APAP) Comparison Guide. This guide stacks up every APAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular APAPs, or all APAP machines we sell.

      Compare Most Popular APAP Machines

      Compare All APAP Machines

    • BiPAP, VPAP and BiLevel Comparison Guide. This guide stacks up every BiPAP machine we sell, feature by feature. If you don't know the meaning of a feature, click the question mark for a definition. The links below will take you to the most popular BiPAPs, or all BiPAP machines we sell.

      Compare Most Popular BiPAP Machines

      Compare All BiPAP Machines
    What comes with my machine?
    Machines come with a six foot hose, power cord, at least one filter, and manuals. Most manufacturers include a carrying case which is designed specifically for their equipment. CPAP, APAP, and BiPAP machines do not come with a delivery system or mask. CPAP masks must be purchased separately.

    To see the list of what specifically comes with each machine, you can Browse for a machine. Then on the product page, click the "Specs" tab to see a full list of what comes with the machine.

    Do all CPAPs use filters?
    Yes, all CPAPs use at least one filter that is usually a type of foam material and washable. Some CPAPs offer finer filtration with the addition of a disposable paper filter.

    Cleaning and changing filters is the only maintenance required for a CPAP machine.

    The filters are located at the back of the machine at the air intake.
    Are prescriptions required for mask, machine, humidifier, and Provent purchases?
    Yes. Federal law requires we have a valid prescription on file before we ship your mask, machine, humidifier, or Provent.

    We provide many easy ways to get your prescription:
    • We can request your prescription for you! When you checkout, just let us know you would like us to request your prescription, or you can log into your account to have us request your prescription.
    • Fax your prescription to our toll free fax number: 866.353.2727, or our international fax number: 713.541.7370
    • Email your prescription to cpap@cpap.com
    • Upload your prescription in your account, under the Prescriptions Section
    • Ask your doctor to fill out our prescription form. We have both a standard prescription form and a Provent prescription form.
    For more information on prescriptions, please see our Prescription Section of the Learning Center.
    What is ramp?
    The ramp button on a machine is a feature that allows for a gradual pressure build-up to your prescribed pressure. The feature is enjoyed by those with high pressures because it eases up to their pressure.
    What is exhalation relief?
    Exhalation relief is a comfort feature which reduces the air flow at the time of exhalation, making the breathing process more natural.

    The following are the different types of exhalation relief names by manufacturer.

    • Philips Respironics = C-Flex, C-Flex+, A-Flex and Bi-Flex
    • Resmed = EPR (Expiratory Pressure Relief)
    • 3B Medical = RESlex
    • Apex Medical = PVA (Pressure Variation Algorithm) Pressure Relief
    • Curative Medical = EUT (Expiratory Unloading Technology)
    • DeVilbiss = SmartFlex
    • Fisher & Paykel = SensAwake Technology
    • Human Design Medical = Z-Breathe
    • Somnetics = EZEX

    Here are some machines with an exhalation relief feature:

    Transcend Auto miniCPAP™ Machine with EZEX
    PR System One REMStar 60 Series Auto with Bluetooth
    AirSense™ 10 AutoSet CPAP Machine with HumidAir™ Heated Humidifier
    + See More
    What maintenance is required on machines?
    The only care a CPAP, APAP or BiPAP machine requires is to clean or change the filters at the air intake. This keeps the internal parts from accumulating dust. Fine paper filters should be changed out every 30 days, or when they appear soiled. Foam washable filters should be rinsed with clear running water once a week, allowed to air dry, and reinserted.

    Here are some other suggested actions to care for your machine:
    • Keep the area around your machine clean by removing any dust from the area to improve the air quality delivered to your machine and to you.
    • Keep the air intake of the machine unblocked. Curtains, bedding, and papers can easily block the air intake of your machine, reducing the airflow.
    • If a humidifier is used with your therapy, do not pick up the machine with the humidifier attached. With most machines it is easy to spill water from the humidifier chamber into the machine causing damage. Manufacturer warranties are voided by water damage to the machine. To avoid this, remove the chamber from the humidifier and then remove the humidifier from the machine rather than transporting them together.
    • If a humidifier is used, empty the water from the chamber every morning. Accidents happen. If a family pet or family member moves the machine and humidifier with water in the chamber it is more likely that water could be spilled into your machine. Water damage to a machine voids the manufacturer warranty.
    How do I use a battery to operate my CPAP?
    All machines can connect to DC power. Some machines are configured to operate on DC Power and have a DC power outlet. Other machines require AC power and will need an Inverter that turns DC power to AC power.

    Having the proper equipment is the biggest key to successfully operating the machine from a battery. For example, if your machine does have a DC outlet and you want to run your machine from a marine battery, be sure to get the correct DC cable for the machine, as well as an adapter cable with alligator clips that fits over the cigarette lighter plug.

    CPAP.com sells complete battery kits with everything you need for many machines including the correct cables for those machines and batteries. You can see if there is a battery kit available for your machine Here. If you have questions about the specific power needs of your machine, review the 'Power' tab found on the machine's product page, or give us a call at 1-800-356-5221.
    What is the difference BiPAP and BiPAP ST?
    A BiPAP (also referred to as a BiLevel or VPAP) delivers two set pressures, a higher pressure for inhalation and a lower pressure for exhalation.

    BiPAP and BiPAP ST machines are similar, as they are both designed to provide the same airway pressure. The difference between a BiPAP and a BiPAP ST is the Spontaneous Timed feature. The ST responds to the user when the minimum number of breaths per minute has not been met. This machine ensures all breaths occur by triggering the user to take another breath within the minute.

    For example, a BiPAP might be set at the following:
    • Inhalation Pressure - 10
    • Exhalation Pressure - 5
    In this case, a BiPAP will provide an IPAP of 10 and EPAP of 5.

    A BiPAP ST might be set at the following:
    • Inhalation Pressure - 10
    • Exhalation Pressure - 5
    • 12 BPM (Breath Per Minute)
    Similarly to the regular BiPAP, the BiPAP ST will provide an IPAP of 10 and EPAP of 5, and will additionally monitor if you inhale 12 times within the minute. Please Note: The ST will not breathe for you, rather it will prompt the user to take a breath.
    What does a BiPAP prescription need to say?
    A BiPAP prescription must contain all of the following information:
    • One of the following words or phrases: "BiPAP", "BiLevel", "VPAP"
    • Your physician's contact information
    • Your physician's signature
    • The patient's full name
    • Your inspiration pressure (Also called IPAP or breathing in pressure)
      • Example: IPAP 13 CM/H20
      • Example: IPAP 13
      • Example: IPAP 4 CM/H20
      • Example: IPAP 4
    • Your expiration pressure (Also called EPAP or breathing out pressure)
      • Example: EPAP 13 CM/H20
      • Example: EPAP 13
      • Example: EPAP 18 CM/H2O
      • Example: EPAP 18

    Here are some of our top selling BiPAP machines:

    IntelliPAP BiLevel Machine with SmartCode
    AirCurve™ 10 S BiLevel Machine with HumidAir™ Heated Humidifier
    DreamStation BiPAP Pro Machine
    + See More
    What is CPAP therapy?
    CPAP stands for Continuous Positive Airway Pressure. CPAP therapy is the most commonly recommended, and the most effective, treatment for obstructive sleep apnea.

    A CPAP machine provides air at a constant prescribed pressure. The air is delivered to the person through a tube and a CPAP mask. CPAP therapy provides a constant airflow which keeps the airway open so uninterrupted breathing is maintained during sleep. The air stream eliminates Sleep Apnea events and allows the person to get a restful sleep.

    The level of air pressure required to maintain your airway is determined during your sleep study. Your doctor will write a prescription for a CPAP machine set at that pressure.

    CPAP therapy is delivered through a nasal mask that seals around the nose, nasal pillows which seal at the nasal opening, or nasal prong masks that seal inside the nares. Full face masks are available for a person who breathes through both the nose and mouth. Many innovative and comfortable options are available and advances in the delivery of CPAP therapy are continually occurring.

    For instance: Some machines offer a comfort feature such as FLEX or EPR technology. It provides exhalation relief, a slight drop in pressure at the time of exhalation to help make therapy more natural. APAP, BiPAP and BiLevel machines offer various levels of pressure throughout the night.
    What are the CPAP, BiPAP and Sleep Apnea related billing codes?
    • EO601 RR is CPAP rental.
    • E0601 NU is CPAP purchase.
    • A7034 is CPAP nasal mask, including all nasal masks, Nasal Aire, Breeze, Spiritus.
    • A7034 is CPAP Nasal mask cushion.
    • A7030 is CPAP Full Face mask.
    • A7031 is CPAP Full Face mask cushion.
    • A7044 is CPAP Oral Interface.
    • A7027 is Hybrid brand
    • A7028 is Hybrid cushion
    • A7029 is Hybrid nasal pillow
    • A7027 is Liberty Brand
    • A7028 is Liberty cushion
    • A7029 is Liberty nasal Pillow
    • A7046 is CPAP Humidifier Chamber.
    • A7037 is CPAP tubing, long and short hoses.
    • A7038 is CPAP disposable filter.
    • A7039 is CPAP gross particle (foam) filter.
    • A7035 is CPAP headgear.
    • A7033 is CPAP nasal pillows.
    • A7036 is CPAP chinstrap.
    • E0561 NU is CPAP Passover Humidifier
    • E0562 NU is CPAP Heated Humidifier
    • E0470 RR is BiPAP rental.
    • E0470 NU is BiPAP purchase.
    • E0471 RR is BiPAP-ST rental.
    • E0471 NU is BiPAP-ST purchase.

    Other CPAP items are listed under E1399, which is miscellaneous.
    What data capable machines are available?
    CPAP machines which record full data (such as AHI and leak info):


    AutoPAP ("Autotitrating CPAP" or "APAP") machines which record full data:


    BiLevel ("BiPAP") machines which record full data:


    CPAP Machines that only record compliance data (hours used) are:

    What does a BiPAP ST prescription need to say?
    A BiPAP ST prescription must contain all of the following information:
    • One of the following words or phrases: "BiPAP ST", "Synchrony ST", "VPAP ST"
    • Your physician's contact information
    • Your physician's signature
    • The patient's full name
    • A backup rate or BPM setting.
    • Your inspiration pressure (Also called IPAP or breathing in pressure)
      • Example: IPAP 13 CM/H20
      • Example: IPAP 13
      • Example: IPAP 4 CM/H20
      • Example: IPAP 4
    • Your expiration pressure (Also called EPAP or breathing out pressure)
      • Example: EPAP 13 CM/H20
      • Example: EPAP 13
      • Example: EPAP 18 CM/H2O
      • Example: EPAP 18
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