Innovation and technology

Algorithms



AutoSetTM

In AutoSet mode, the device provides only the amount of pressure required to maintain upper airway patency. The AutoSet algorithm adjusts treatment pressure as a function of inspiratory flow limitation, snore and apnoea, while the device analyses the state of the patients’ upper airway on a breath-by-breath basis and delivers pressure within the allowed range according to the degree of obstruction.

Available in the AirSense 10 AutoSet and AirSense10 AutoSet for Her devices.

AutoSet for Her

The new algorithm in the AirSense™ 10 AutoSet for Her device is based on ResMed’s AutoSet algorithm and delivers therapeutic responses that have been tailored to the characteristics of obstructive sleep apnoea (OSA) in women.

Research has shown that women with OSA have more upper airway resistance than the general OSA population1, which is why the AutoSet for Her algorithm has been designed to be more sensitive to flow limitation.

As a result, the algorithm provides more subtle changes in therapy pressure to help minimise any sleep disturbance. The AutoSet for Her algorithm also automatically adjusts the minimum AutoSet pressure if multiple apnoeas are occurring below a certain threshold.

Available in the AirSense 10 AutoSet for Her device.

S mode

Ideal for non-compliant CPAP patients, S mode features a fixed-pressure and is designed to deliver effective, comfortable therapy for a wide range of patients. In S mode, you may set two treatment pressures – one for inspiration (IPAP) and one for expiration (EPAP). The device senses when the patient is inhaling and exhaling and supplies the appropriate pressures accordingly. The difference between IPAP and EPAP levels helps determine the tidal volume. (For related features see Triggering and cycling, TiControl™ and Easy-Breathe.)

Available in the AirCurve 10 S device.

Technological features

 

AutoSet Response™ mode

ResMed’s AutoSet algorithm now allows for additional customisation of therapy with the new AutoSet Response mode, which offers all the benefits of the enhanced AutoSet algorithm with gentler pressure increases for additional comfort.

For patients who are sensitive to faster changes in pressure during therapy, AutoSet Response can be set to either Standard or Soft. If set to Soft, patients will receive gentler pressure rises during therapy.

Patients who use the AutoSet Response feature will still get the benefits of ResMed's AutoSet technology including central sleep apnoea (CSA) detection.

Available in the AirSense 10 AutoSet and AirSense 10 AutoSet for Her devices.

AutoRamp™ feature

The new AutoRamp feature with sleep onset detection helps make therapy comfortable from the moment the patient turns on their device. Built into ResMed’s AirSense 10 devices, this ramp feature is activated automatically, so you’ll no longer need to spend time adjusting each patient’s ramp setting.

As soon as the patient turns on their device, AutoRamp begins – delivering a lower start pressure to help patients fall asleep with ease. Then, using its unique sleep onset detection capability, AutoRamp detects that the patient has fallen asleep, and then starts to comfortably ramp up to the prescribed pressure. So patients receive their prescribed pressure from the moment they’ve fallen asleep.

With ramp times automatically adapting to each patient’s individual sleeping patterns, AutoRamp gives your patients a tailored start to therapy, and makes the most of every valuable moment of therapy time.

Available in the AirSense 10 Elite, AirSense 10 AutoSet and AirSense 10 AutoSet for Her devices.

Central sleep apnoea (CSA) detection

CSA detection uses the Forced Oscillation Technique (FOT) to determine whether a patient’s airway is open or closed during an apnoea. When an apnoea has been detected, small oscillations in pressure (1 cm H2O peak-to-peak at 4 Hz) are added to the current device pressure. The CSA detection algorithm uses the resulting flow and pressure (determined at the mask) to measure whether the airway is open or closed.

Available in all AirSense 10 devices.

Cheyne-Stokes respiration (CSR) detection

Cheyne-Stokes respiration is a form of sleep-disordered breathing characterised by a periodic waxing and waning of respiration resulting in variations in blood oxygen saturation.

ResMed’s new Cheyne-Stokes respiration detection feature helps you identify patients on fixed or auto-adjusting pressure devices, but who may present with CSR breathing patterns. Throughout the night, the intelligent algorithm continually monitors a patient’s breathing pattern, checking cycle lengths and searching for indications of CSR.

Available in all AirSense 10 devices.

CPAP mode

Continuous positive airway pressure (CPAP) is a type of therapy that delivers pressurised air at one fixed pressure throughout the night to keep your patients’ airways open so that they don’t stop breathing in their sleep.

Available in all AirSense 10 and AirCurve 10 devices.

Easy-Breathe feature

The Easy-Breathe waveform intelligently recreates a patient’s individual breathing pattern, so breathing feels more natural and therapy is more comfortable.

Expiratory Pressure Relief (EPR™)

Designed to make therapy more comfortable, Expiratory Pressure Relief (EPR) maintains optimal treatment for the patient during inhalation and reduces the delivered mask pressure during exhalation.

Available in all AirSense 10 devices.

Leak management

The AirCurve 10 series of devices monitor and compensate for leak by continuously and automatically adjusting the baseline flow. This enables reliable delivery of therapy pressure while maintaining patient-device synchrony. (For relevant algorithms, see Vsync.)

Available in all AirCurve 10 devices.

Ramp

Designed to make the beginning of treatment more comfortable, ramp is available in all modes. Ramp time is the period in which the pressure gradually increases from a lower, more comfortable start pressure to the prescribed treatment pressure.

Available in all AirSense 10 and AirCurve 10 devices.

Respiratory Effort Related Arousals (RERA) reporting

RERAs are periods of increased respiratory effort leading to an arousal.1 These flow-based RERA events are logged and stored as summary and/or detailed data and can then be viewed in AirView™, ResMed’s cloud-based patient management system.

RERA reporting is available on the AirSense 10 AutoSet for Her in all modes. (See Unique Therapy for Women).

Available in the AirSense 10 AutoSet for Her device.

TiControl - inspiratory time control

Unique to ResMed bilevel devices, TiControl allows you to set minimum and maximum limits on the time the device spends in IPAP. The minimum and maximum time limits are set at either side of the patient’s ideal spontaneous inspiratory time, providing a window of opportunity for the patient to spontaneously cycle to EPAP.

The minimum time limit is set via the Ti Min parameter and the maximum time limit is set via the Ti Max parameter.

TiControl’s Ti Max and Ti Min parameters play a significant role in maximising synchronisation by effectively intervening to limit or prolong the inspiratory time when required. This ensures synchronisation even in the presence of significant mouth and/or mask leak.

Working in sync with TiControl, Vsync ensures reliable breath detection (patient–device synchronisation) even in conditions of high leak.

Available in AirCurve 10 VAuto and AirCurve 10 S devices.

Triggering and cycling

Under normal conditions, the device triggers (initiates IPAP) and cycles (terminates IPAP and changes to EPAP) as it senses the change in patient flow. Patient breath detection is enhanced by ResMed’s automatic leak management. In addition, the device has adjustable trigger/cycle sensitivity to optimise the sensing level according to patient conditions.

Available in all AirCurve 10 devices.

Vsync

Vsync is a leak management algorithm that compensates for unintentional mask leak, so that patients receive their prescribed therapy pressure.

Available in all AirCurve 10 devices.

Climate Control

Climate Control is an intelligent system that controls the HumidAir™ humidifier and the ClimateLineAir™ heated air tubing to deliver constant, comfortable temperature and humidity levels during therapy.

Automatic adjustment

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

- ambient room temperature and humidity values

- flow due to pressure changes

- flow due to mask or mouth leak

Climate Control Auto setting

When used with ResMed’s new HumidAir™ heated humidifier and ClimateLineAir™ heated tube, each device is designed to automatically deliver therapy at the most comfortable temperature and humidity levels—thanks to the enhanced Climate Control Auto option. There are no settings to change and no complicated menus to navigate.

Climate Control Manual setting

For patients who want greater control over settings, the Climate Control Manual setting lets the patient adjust the temperature and humidity to the setting that is most comfortable for them.

In Climate Control Manual, the tube temperature and humidity level can be set independently, however rainout protection is not guaranteed.

Tube temperature

If the air in the mask feels too warm or too cold, the patient can adjust the temperature to find what is most comfortable or turn it off completely. The tube temperature can be set to anywhere between 16-30°C.

The temperature sensor located at the mask end of the ClimateLineAir heated tube enables the system to automatically control the temperature of the air delivered to the patient. This ensures the temperature of the air delivered to the patient does not fall below the set minimum temperature, therefore maximising breathing comfort for the patient.

Humidity level

The humidifier moistens the air and is designed to make therapy more comfortable. If the patient is getting a dry nose or mouth, turn up the humidity. If the patient is getting moisture in their mask, turn down the humidity.

The humidity level can be set to Off or between 1 and 8, where 1 is the lowest humidity setting and 8 is the highest humidity setting.

For each humidifier setting, the Climate Control system delivers a constant amount of water vapour, or absolute humidity (AH), to the patient’s upper airway.

Available in all AirSense 10 and AirCurve 10 devices.

For a fully integrated approach to patient care, prescribe ResMed Air Solutions products.

References

  • 01

    Mohsenin V. Gender differences in the expression of sleep-disordered breathing: role of upper airway dimensions. Chest 2001; 120(5):1442-7.

  • 02

    Phillips B & Kryger, MH, Chapter 92, Management of Obstructive Sleep Apnea-Hypopnea Syndrome: An Overview; In Principles and Practice of Sleep Medicine, M Kryger, D Roth and W Dement, Editors. 2005, Elsevier Saunders: Philadelphia. P. 1109-1121.