Bells and Whistles: Do you know enough about your CPAP Machine?

Tracy R. Nasca - April 18, 2011

What do you know about your CPAP machine?  Are you aware that they offer patient controlled comfort features?  Did you know these features might need to be enabled for you to use them?  Are your features enabled?

Years ago, a CPAP machine might have been described as a fan in a box; preset to deliver a patient specific rate of air pressure via a mask worn over the nose.  CPAP is prescribed to keep the airway blown/splinted open preventing apnea events caused by airway collapse or blockage.  Over the past decades, the manufacturers have developed wonderful features, bells and whistles if you will, designed to increase patient comfort and thus compliance.

What are the bells and whistles and how do they differ among the top 3 manufacturers of CPAP equipment? 

Ramp

Ramp is a newly diagnosed patients BFF- best friend forever.  The ramp feature initiates pressure at a low setting and slowly increases over a preset period of time.  This allows the patient to receive a lower and more comfortable delivery of air, allowing time to transition in to sleep before the optimal pressure presents.   Most machines are capable of ramping up from the lowest offered CPAP pressure of 4 and over a period of time between 15 and 30 minutes.

Example:  Your CPAP pressure is 10.  Ramp might be set to begin delivery of air set at 6 and ramp up to 10 over a period of 30 minutes.  This helps the patient ease in to sleep before the higher and necessary pressure of 10 is delivered.  Many machines have a ramp button that can be used again to reset the ramp cycle.

Fisher & Paykel

CPAP devices manufactured by Fisher & Paykel Healthcare offer proportional ramp which allows patients to start therapy at lower, more comfortable pressure during awake time, and deliver the required pressures as patients fall sleep.

Philips Respironics

This option allows the patient to adjust their amount of Ramp time up from 0 to 45 minutes in increments of 5 minutes until the prescribed treatment pressure is achieved.

ResMed

Ramp is designed to make the beginning of treatment more comfortable at the start of therapy.  This option allows the patient to adjust their amount of Ramp time up to 45 minutes.  Minimum starting pressure is 4 cm H2O and gradually increases in 0.2 cm H2O increments to the treatment pressure.  The starting pressure can be set higher, if desired.

In CPAP mode during Ramp time, the pressure increases from a low pressure at the start of therapy to the prescribed treatment pressure.

In bilevel modes, Ramp time defines the period during which the pressure gradually increases from a lower, more comfortable start pressure to the minimum treatment pressure and, finally, to the set EPAP pressure.

Pressure Relief

CPAP stands for Continuous Positive Airway Pressure and is just that; a constant and continuous flow of air that the patient must inhale and then exhale over.  One of the biggest challenges adjusting to CPAP is the overwhelming feeling of that continuous flow of air pressure upon exhalation.  All 3 manufactures now offer a resolution to this challenge by sensing and / or reducing the machine pressure during exhalation.

Example:  Your CPAP pressure is 10.  You have no problem inhaling that delivery of air, but when you begin to exhale while the air is still being delivered, you may feel overwhelmed, claustrophobic or even experience a choking sensation. 

Fisher & Paykel

Patients commonly arouse from sleep which can sometimes lead to a full awakening. During this period, many patients are intolerant of the delivered pressures which may lead them to knowingly or unknowingly abandon CPAP therapy for the night. Therefore it is important to provide as much comfort as possible during these wakeful states to help facilitate the return to sleep.

SensAwake™ does this by searching for a pattern of irregular breathing which occurs at the transition from sleep to awake,   and responds by reducing the pressure promptly to aid the transition back to sleep.  Hence, Ramp helps tolerate pressure when you are attempting to fall asleep and SensAwake assist in providing comfort during the transitional periods of sleep.

Philips Respironics

Flex Technology is designed to enhance traditional CPAP therapy; maintaining effective therapy at minimal pressures. Users new to CPAP equipment find the Flex feature provides airflow at just the right pressure relief for every breath and makes adapting to CPAP therapy easier. 

C-Flex offers a comfortable way to deliver sleep therapy by giving pressure relief at exhalation. Pressure is lowered based on a breath-per-breath analysis and provides up to 3 levels of relief based on the patient's expiratory flow.

C-Flex Plus is a new enhancement added to Philips Respironics Pro and Auto CPAP machines. Similar to C-Flex, the technology provides pressure relief during exhalation based on expiratory flow. C-Flex+ minimizes the pressure transition and provides additional comfort when in fixed-CPAP mode. In addition, C-Flex+ softens the breathing cycle between inhalation to exhalation. 

ResMed

Expiratory pressure relief (EPR™) can make breathing more comfortable for patients and is an effective alternative to CPAP therapy. However, unlike other leading CPAP alternatives, EPR features several options that enable you to reliably and predictably control patient therapy while delivering a higher level of patient comfort.

When the patient exhales, the ResMed flow generator detects the beginning of exhalation and reduces motor speed to drop pressure. The patient or clinician chooses one of three comfort levels to determine the degree by which pressure will drop.

Setting 1– mild comfort (1 cm H2O) Setting 2– medium comfort (2 cm H2O) Setting 3– maximum comfort (3 cm H2O)

Heated Humidification

CPAP Humidifiers were introduced in the 1980’s when it became clear that warming and moistening the CPAP airflow would help resolve nasal lining dryness and nasal congestion. In the 80’s and 90’s they were perceived as optional accessories.   As years passed and large numbers of patients abandoned cpap therapy due to its many challenges, science and research unmistakably showed that heated humidification did indeed increase compliance.  Simply put, heated humidification just makes for a more pleasant CPAP experience that benefits most patients no matter what climate they live in.  In today’s world, heated humidification is more widely recognized as a necessity and not a luxury and optional accessory.

Example:  The air delivered via CPAP is received by the patient at the same temperature as the bedroom sleeping environment.  So during the winter months, the air may be cooler and drier than desired.  In summer months, air conditioned bedrooms may also deliver cool air.  The nasal lining is highly vascular and when subjected to the continuous pressurized air flo delivered by CPAP, it can result in a painful drying affect, stuffy nose or even a runny nose. 

Fisher & Paykel

Fisher & Paykel Healthcare has been a leader in humidification technology in hospitals for over 30 years, developing products specifically for the ventilator patients in the Intensive Care Units.  With this in-depth knowledge they adapted their advanced intensive care humidification technology so that it could be used in the home with CPAP.   Today they offer a comprehensive range of CPAP units integrated with advanced humidification technology called ThermoSmart™. The clinically proven ThermoSmart™ Technology, with its unique heated breathing tube, mimics the physiology of the nose to heat and humidity the air, without condensation in the tube Patients will experience new levels of sleep comfort as humidity levels remain constant through the night, regardless of ambient room temperature changes. 

Philips Respironics

The Philips Respironics CPAP humidifier and water chamber design manage rain-out and water damage. System One Humidity Control technology analyzes ambient temperature and patient airflow to reach relative humidity at the mask. You can choose from 5 levels of relative humidity.

ResMed

S9™ devices, when used in conjunction with the H5i™ and ClimateLine™ heated tubing, offer a feature called Climate Control.

Climate Control enables the automatic delivery of a constant value of absolute humidity to the patient’s upper airway while protecting against rainout and allowing patients to select the temperature that’s most comfortable for them.  With five integrated sensors to measure flow, humidifier output, ambient temperature, ambient humidity and temperature at the mask, optimal humidification is delivered at the patient’s desired temperature throughout the night and from season to season.

Rainout protection Rainout refers to the water or condensation that collects in the patient’s tubing or mask. Rainout is a common side effect of using a humidifier due to the humidified air cooling as it travels down the tubing and into the mask. Rainout occurs when relative humidity, which is a measure of the air’s capacity to hold water vapor, exceeds 100%. Climate Control protects the patient from rainout by maintaining a target relative humidity of 80%, as well as maintaining the temperature of the air delivered to the patient without compromising the amount of absolute humidity delivered.

Automatic constant humidity delivery for each temperature setting, the Climate Control system delivers a constant amount of water vapor, or absolute humidity, to the patient’s upper airway.

The H5i and ClimateLine heated tubing are controlled by the Climate Control algorithm to deliver constant humidity and temperature outputs. The system adjusts automatically according to changes in:

• ambient room temperature and humidity values
• flow due to pressure changes
• flow due to mask or mouth leak

When the ClimateLine heated tubing is connected and Climate Control is enabled, the patient can adjust the air temperature to find the setting that is most comfortable for them. When set to Auto, Climate Control prevents rainout by maintaining 80%relative humidity in the delivered air. If Climate Control is set to Manual, the humidity level and heated tube temperature can be set independently.

You choose the bells and whistles!

CPAP is the best known treatment for sleep apnea yet it has many challenges. Ingenuity and cutting edge technology provided by the manufacturers has greatly improved the ease of use and comfort level to give patients the best possible chance to reach compliance sooner.  Consider your challenges and learn about the comfort features available on your CPAP machine.  Take advantage of all of the bells and whistles at your disposal.  With your CPAP in hand, visit your local equipment provider and ask them to familiarize you with all of the comfort features on your machine.

Whether you are newly diagnosed and just beginning CPAP therapy, or a veteran user, the goal is achieving healthy and restorative sleep.  Make sure you are using all of the incredible the tools at your disposal!