The Medtronic Paradigm REAL-Time Revel
by dana lewis
I am a long-time MiniMed Paradigm pump user, so when I had the chance to test drive the new MiniMed Paradigm REAL-Time Revel System, I jumped at the opportunity. The Revel, as we noted previously (see New Now Next from diaTribe #21), is the next pump/continuous glucose monitoring (CGM) platform in the REAL-Time system (and current users who are still under warranty can upgrade through Medtronic’s Paradigm Pathway program). As before, the REAL-Time series features integration with CGM on the home screen of the pump. But the selling points of the Revel seem to be the new predictive CGM alerts, smaller dosing increments and ratio settings, and alert-based navigation. Alert-based navigation means that if you get an alert (i.e., high or low blood glucose reading), it will guide you to the appropriate menu or screen to take action on the alert. (Previously, users had to acknowledge the alert, then find the correct pathway to take action if necessary.) This, and many other improvements to the user interface, makes the Revel an evolutionary step for Paradigm pumpers.
The first big change I noticed from the old Paradigm to the Revel was the increased number of graphs. Instead of a 3- or 24-hour graph, I was able to access 3-, 6-, 12-, or 24-hour graphs. There’s also the ability to set different thresholds for high and low glucose alerts (eight total) at different times of the day. This, and the following feature, would sell me on the Revel over my old Paradigm pump any day.
The "insulin on board" or "active insulin" ratio (calculated by the user's settings) is now available in THREE places. This is a huge improvement and time saver: I didn't realize how much time I previously wasted going through the Bolus Wizard calculation, inserting my blood glucose as “99” and my carb intake as “0” to find out how much active insulin was on board. Now, I can see it on the status screen (by pushing the back button past the CGM graphs), on the screen if I am using an "easy" or manual bolus, or in the old location on the Bolus Wizard calculation screen.
However, as a CGM system, the Revel wasn’t quite as revolutionary as I had hoped. The distinguishing new feature of the Revel system is the predictive alerts: these alerts use an algorithm to study the trends of your blood glucose levels. If you are rising or falling too fast over a period of time, the algorithm is designed to predict if you will go beyond your pre-set “high” or “low” thresholds. If so, it gives you a “predictive” alert for a high or low. Because I wear the Paradigm pump but another company’s CGM, I was hoping the new CGM would beat my current CGM system’s performance with predictive alerts. However, I continued to find that the Revel appeared to have a longer lag time between my CGM readings and my actual glucose levels (tested with my fingers on my usual calibrated meter).
Despite this, I found the predictive alerts to be useful. The Revel allows you to customize your “rate of change” alerts (which contribute to the predictive alerts) for when your glucose numbers are trending rapidly up or down. This was the best way for me to help the Revel alert me to highs or lows ahead of time. Surprisingly, my pump trainer recommended setting the rate-of-change alerts to a longer time; she mentioned that many users get frustrated by the number of alerts they have to acknowledge. However, I appreciated this tweak that made the alerts more relevant and timely than before.
The Revel has other new and improved settings, like the menu for changing your infusion set and reservoir. Before, for changing infusion sets and reservoirs, the menu was labeled "prime" and included basic terminology for rewinding and priming the pump. Now, the Revel double checks that you have detached the tubing from your body, questions that you have drops at the end of the tubing after priming, and so on. While it can be a bit of a hassle for the advanced (or impatient!) pump user, we appreciate the idea of additional safety checks - it is also a smart addition for those new to pumps or those who are more cautious about replacing sites and reservoirs.
For anyone on small amounts of insulin, I can imagine that the tiny dosing increments (now at 0.025) would be a notable improvement in quality of pumping. Also, for those with very insulin resistant type 2 diabetes considering pumps, my pump trainer pointed out that there is now the option to increase your insulin-to-carb ratio to 1:1, making it easier to bolus for meals and snacks.
There are a few other features and changes, including the opportunity to set a “missed meal bolus alert,” so if you don't bolus in a certain time frame, the alarm sounds. I never used this feature because my schedule is so irregular, but the sister feature that I can imagine will save some lives is the automatic shutoff. This isn't connected to the CGM readings (like with the Paradigm Veo, now only available in the UK, Ireland, and other parts of the EU), but you can program your pump to shut off completely if you haven't touched it in a certain time span – a great safety feature for people living alone when used properly.
The last obvious change in the Revel system is the new look. It is advertised as a new "overlay” that “enhances the look and feel of the pump.” The overlay is the casing around the screen that includes the buttons on the front of the pump. Before, my purple pump had a dark grey overlay with light grey and blue buttons – the Revel I chose has a bright purple overlay (which in retrospect may have been a little bold for my tastes), though the pump is available in a number of different colors. It’s good to see that we’re moving toward more alternatives, broader choices, and greater customization than was previously possible – moving toward more of a designer feel is definitely a positive in my view.
In sum, the improvements made with the Revel are a great next step and are not to be underappreciated; they redress a number of the pet peeves I had with my current pump. However, after four years, I had hoped for a little more in a new pump and CGM system than user interface improvements – with more and more researchers flooding in to pursue the artificial pancreas, hopefully greater advances in pumping technology are on the way.
Active Insulin/Insulin on Board now viewable in three places
Easier menu navigation
0.025 insulin dosing increments and 1:1 carb ratios
Eight settings for adjustable high/low thresholds
3-, 6-, 12-, and 24-hour glucose graphs
Rate of change alerts
recommendations and improvements:
More options for pump casing and “overlay”
Improving the accuracy/time lag of predictive alerts
Make alarm settings audible at night/adjustable