Copyright 2003, Insulin Pumpers and Eric Schmidt <firstname.lastname@example.org>
|| Minimed 508|
The Minimed 508 is very similar in physical design as its predecessors the 507 and 507C, but with many additional software features added, as well as the addition of an optional remote control. The 508 supports flexible insulin delivery with 3 available basal programs and Audio and extended bolus options. It has a large backlit LCD screen for displaying information and is programmed with the use of 4 flush buttons on the front.
Technical Feature Details
3 x 1.9 x 0.87 inches
- Physical Delivery Mechanism
Proprietary stepper motor design with captive lead screw. Delivers insulin in discrete 0.1 unit increments (U-100 insulin) per cycle (each "click").
The insulin cartridge is manually primed by pushing on the plunger prior to placing the cartridge into the pump. A motorized "Prime" feature is available to deliver the small canula/needle filling bolus without adding that amount into the daily total (for instance, when a new infusion set is inserted).
- Battery Type
The Minimed 508 requires 3 standard 357 watch batteries which are inserted into a "battery carrier" bracket which seats into the pump.
- Cartridge Type and Capacity
Proprietary plastic cartridge with 3.0 ml capacity (300 units of U-100) standard or 1.5 ml short-fill (with provided adapter). The short-fill option allows the Luer lock connector to be recessed within the pump housing.
- Water Resistance
Conforms to IEC60529 IPX7 standard. Splash-resistant and resistant to accidental submersion in shallow water. Submersion not recommended. For swimming or bathing disconnection or placing the pump in a watertight case is recommended.
Four year warranty.
Functional Feature Details
- Basal Programming Options
The 508 provides up to three different basal profiles which can be used to adjust for events such as exercise days, differing weekday and weekend schedules, sick days, etc. The profiles are called "Standard", "Pattern A", and "Pattern B" which can be programmed to fit the individual's needs.
Basal rates can be programmed for between 0.0 to 35.0 units per hour in 0.1 unit increments. A user-programmable hourly basal cap is set at the factory for 2.0 units/hour (can be increased up to the 35.0 units per hour hard limit). Each basal profile can contain up to 48 segments which consist of the rate, start time, and duration. The segments can range from 30 minutes to 24 hours, in 30 minute increments.
- Temporary Basal Rate
This feature allows the user to set a temporary basal rate to override the current basal program. A fixed rate is set (which could be lower or higher than the current basal rate) for a specified time duration from 30 minutes to 24 hours, in 30 minutes increments.
- Bolus Programming Options
The 508 allows 4 different bolus methods - Normal, Audio, Square Wave, and Dual Wave. A Normal bolus starts delivery immediately after it is entered, and can range from 0.1 units to 35.0 units (depending in user adjustable Maximum Bolus parameter).
The Audio bolus must be enabled within the "Setup II" menu before it can be used and a step size of either 0.5 or 1.0 units selected. To deliver an audio bolus, the "up" scroll button is pressed multiple times until the desired dosage is reached, followed by a press of the "act" button (for example, with a step size of 0.5 you would press the button 4 times to get a 2.0 unit bolus). Each time the button is pressed, a beep is sounded. Once the "act" button is pressed, the pump sounds a series of beeps to verify the dosage, and a second press of the "act" button is required to verify and activate delivery.
The Square Wave bolus program is an extended bolus which requires programming in the bolus amount as for a Normal bolus, plus a duration which can vary between 30 minutes to 8 hours in 30 minute increments. The "Variable Bolus" setting must be turned on under the "Setup II" screen before this feature can be used.
The Dual Wave bolus program is a variation of an extended bolus, and is basically a combination of a Normal bolus and a Square Wave bolus. First, the user is prompted to enter a bolus of insulin for immediate delivery (the Normal portion). Then, the user is prompted to enter an extended bolus amount with time duration (the Square Wave portion). As with the Square Wave bolus, the "Variable Bolus" setting must be turned on under the "Setup II" screen before this feature can be used.
It should be noted that a Normal or Audio bolus may be programmed concurrently with, and on top of, a Square Wave bolus or the extended portion of a Dual Wave bolus.
- Remote Control
Yes. The remote control is an optional feature which allows the user to set an Audio bolus and Suspend/Restart the pump without having to touch the pump. The remote itself is about the size of a car remote, being approximately 2 x 1.5 x 3/8 inches in dimension. The remote has three buttons, titled "stop", "bol", and "act". One 508 pump can be controlled by up to 3 separate remotes. To use one or more remotes, the "RF DEV" setting under "Setup II" must be turned on, and each remote control's serial number must be programmed into the pump.
- User Interface and Display
On the front of the 508 there is a large backlit LCD screen with 4 flush buttons for programming. The "sel" button is used to scroll through the different screens, the "act" button is used as an enter or "activate" button, and the scroll buttons are used to change values while programming the pump. In addition, the "up" scroll button is used to access the Audio bolus feature, and the "down" scroll button is used to activate the backlight.
The main pump screen displays the time. By pressing the "sel" button, the user can step through the other 8 screens to access other features. All nine of these screens are listed below.
- Time of Day (default main screen)
- Basal Rate
- Temporary Basal Rate
- Daily Totals
- Prime & Low Reservoir Volume
- Setup I
- Setup II
- Vibrating Mode
- Child Lock Mode
- Selected Alarms and Error Messages
- - S - STOPPED
- LO BATTERY
- OFF NO POWER
- NO DELIVERY
Occlusion or empty cartridge
- TEMP BASAL RATE
- - 0 - ALARM
Auto OFF timeout, pump suspended
- E-XX or A-XX
Various error and alarm messages - check manual
The following data can be viewed directly from the 508 insulin pump: Past 24 boluses with time/date, last 7 days of combined bolus/basal daily insulin totals, last 12 alarms or error messages with date/time, last 9 primes with date/time.
With special equipment available to medical providers, additional information can be retrieved from the pump using its two IR interface ports. This includes last 450 boluses with time/date, approximately 90 days of combined bolus/basal daily insulin totals, last 50 alarms with time/date, and last 50 primes with time/date.
- Automatic OFF
This feature will alarm and suspend the pump if no buttons have been pressed for the programmed time limit. That limit can be set from 1 hour to 16 hours in 1 hour increments.