The comparison question this article gets asked most often, answered from the data side rather than the sales side. Between a machine generation and its successor, the therapy algorithms are usually close relatives and the detailed data written to the card is broadly the same shape — so if you already know how to read one, you are not starting again. What tends to change is everything around it: the screen, the setup flow, the humidifier and tube fittings, the cellular reporting, and sometimes whether a card slot is present or populated at all. Two practical notes for anyone buying, new or used: Check that the card slot is there and that a card is in it. Some units ship with the slot empty, and a machine that is not writing to a card is not keeping the detailed record you will want later. A card that has never been in the machine holds nothing retrospectively. On a used machine, check the hours counter and the current settings before anything else. The hours tell you what you actually bought; the settings tell you what somebody else was prescribed, which is not what you were. Nothing on SomniTalk is medical advice. Talk to your own clinician before changing therapy.

The practical difference between the two routes, since this is the article people land on when they ask what the cloud actually gets. The card holds the detailed night: flow, pressure over time, individual events with their timestamps, leak as a trace rather than a number. It is what makes questions like "when in the night does this happen" answerable. The cloud summary holds the headline: hours, an event index, a leak figure, a pressure figure. Enough to confirm you used it and roughly how it went; not enough to work out why a night was bad. Which is why "my app says my AHI was 4.2" and "I looked at my data" are different sentences. If the only record you keep is the summary, the detailed night is gone once the card is overwritten — cards do get reused, and the oldest detail is what goes first.

From the SomniCharts Learn library · AirCurve bilevel and ASV machines log IPAP, EPAP, and pressure support — uniquely rich data. Learn how to read it and what each mode records. Read the full article → https://www.somnicharts.com/learn/aircurve-bipap-asv-data Related reading: CPAP Machines & Devices, APAP vs CPAP vs BiPAP: Machine Modes and the Data Each Produces, ResMed AirSense 11 Data: What Your SD Card Holds (and myAir Hides), Central vs Obstructive Apnea: What 'Clear Airway' (CA) Events Mean, Periodic Breathing & Cheyne-Stokes on Your CPAP Chart Start the discussion below — questions, experiences, corrections welcome. Nothing here is medical advice.

From the SomniCharts Learn library · AHI vs RDI explained: RDI adds RERAs to the count, so it's always equal to or higher than AHI. Learn why a normal AHI can hide an elevated RDI. Read the full article → https://www.somnicharts.com/learn/ahi-vs-rdi Related reading: Understanding Sleep Apnea, What Is a Good AHI on CPAP? AHI Ranges and Residual AHI Explained, RERA and Flow Limitation: The Events That Don't Show in Your AHI, UARS (Upper Airway Resistance Syndrome): The Diagnosis Your AHI Misses, CPAP Event Types Decoded: Obstructive, Central, Hypopnea & RERA Start the discussion below — questions, experiences, corrections welcome. Nothing here is medical advice.

From the SomniCharts Learn library · AHI naturally varies night to night. Learn what drives the swings, why one bad night isn't a crisis, and why trends beat single numbers. Read the full article → https://www.somnicharts.com/learn/ahi-changes-night-to-night Related reading: Troubleshooting & Optimizing CPAP, What Is a Good AHI on CPAP? AHI Ranges and Residual AHI Explained, Why Is My AHI High on CPAP? Causes and How to Find Yours, How to Read Your CPAP Data: A Plain-English Guide to AHI, Leak Rate & Pressure, How to Read CPAP Usage Hours and What 'Compliant' Really Means Start the discussion below — questions, experiences, corrections welcome. Nothing here is medical advice.