InfusiCalc version 3.0: September 2005

Upgrading from Version 1.x

If you already have InfusiCalc v1.x on your palm, you can install the new version of the database, or convert your version 1.x database.

The first time you run InfusiCalc 3.x, you will be prompted to convert the version 1.x database. Your version 1.x database will not be altered, and should you wish to revert to InfusiCalc 1.x, you need simply reinstall it and your old database will still function.

The changes from the old version are detailed on page 22 under “Version History”

Upgrading from Version 2.x

If you have version 2.x of InfusiCalc, just install version 3.x on top of the old one. There is no database conversion required.

Registering a demo version

If you already have InfusiCalc installed on your Palm as a demo, and have now paid for the “registered” version, you need only install one file, “InfusiCalcRG.pdb”.

However, if you have version 1.0, you will need to install both “InfusiCalc.prc” and “InfusiCalcRG.pdb”. You do not have to install the database if you do not want to, and all your version 1.x drugs will be converted to version 3.x.

The List Screen

The list screen shows you all the drugs in the database, or a reduced subset of drugs using either the “show” drop down list, the category popup or the “find” search field (see below). You can choose any drug from the list by tapping on the drug name with the stylus. You will then be taken to the appropriate screen (either infusion or bolus screen) for the drug.

Limiting the List View
You can find a subset of records by:

(i) choosing a category from the Category Popup trigger in the top right of the screen

(ii) entering a letter or range of letters in the Find Field in the bottom left of the screen. InfusiCalc will alter the visible records to those that start with the letter or letters in the find field.

(iii) Choose to show only drugs that have bolus data, infusion data or both, using the Show Popup in the bottom left of the screen

The Infusion Screen

The infusion screen is for calculating continuous drug infusions.

Each aspect of the screen is now explained in detail.

List View Arrow
This arrow in the top right corner will return you to the list screen.

Note Tab
This tab will only be visible if the drug has a note stored in the database. Pressing this icon will reveal the note stored for this particular drug. For example, indications, contraindications, interactions, cautions, and so on. This note can be of any size.

Bolus Tab
If there is bolus data for this drug, the bolus tab will be visible – press this to go to the bolus screen.

Weight Field
This contains the patient’s weight in either kilograms (kg) or pounds (lb). Internally all weights are stored in kilograms and all infusions rates are based on this.

Weight Popup Trigger
This trigger alternates between weight in kilograms (kg) or pounds (lb). When utilised, there will be recalculation of all the displayed figures as required. InfusiCalc uses a method to try and produce the most intuitive result of switching weight types. See Below (General functions of popup triggers in InfusiCalc).

Rate Value Fields
There are three rate value fields. They have variable rates, as determined by the popup triggers. The values found in these fields, and their associated triggers, will always be equivalent. When a new value is entered in a field, the others are updated automatically.

Rate Value Popup Triggers
These triggers may contain many rates, related to the “mass type” of the drug, the “prefix” of the mass type, and whether the drug is weight and time based:

For a given prefix and mass type (eg. milligrams) there will be  4 possible rates:

• mg/kg/min
• mg/kg/hr
• mg/min
• mg/hr

These rates are then repeated for the prefix above and below (in this case, “micrograms” and “grams”)

Mass types available are:

·         Grams

·         Units

·         Moles

·         Equivalents

·         Litres

Prefixes available are:

• nano
• micro
• milli
• kilo
• Mega
• Giga

General Function of Popup Triggers in InfusiCalc.

The two rate popup triggers and the weight popup triggers attempt to calculate the main screen variables in a way that is intuitive. In general, when you use a trigger opposite a field, and the cursor lies within that field InfusiCalc assumes that this figure will not alter and hence it will be used to recalculate all other variables dependent on this figure. For example, if you place the cursor in the weight field, enter a value of "120" then change the weight type from kg to pound directly after this, intuitively you would like to enter a value of "120 pounds", and this is what InfusiCalc assumes (the alternative would be to enter 120 kilograms and then convert it to pounds).

Alternatively, when you use a trigger and the cursor is not within the opposite field, it assumes the current field (the one with the cursor in it) is to remain the same, while the field opposite the trigger is recalculated. For example, if the cursor is in the mls/hr field, and you click the weight popup trigger from kg to pounds, the value in the weight field will be converted from its current value in kilograms to pounds.

Normal Range
This contains the normal ranges of doses specified in the database for that particular drug, and the standard units specified in the database. These can be changed using the Edit Drug/New Drug screen (see below)

Dilution
This section contains three or four fields.

1. The first is the mass field, which contains the mass of drug to be diluted to make up the infusion. This may be based on the patient’s weight (eg. mg/kg).
2. The second field is only present if the first field is weight based. It contains the absolute amount of mass to be diluted. So, if the mass field is, say, “1 mg/kg” and the patient’s weight is 50kg, this field will be “50mg”.
3. The next field contains the volume of diluent in millilitres (mls).
4. The last field is the concentration of the resultant solution. It has a popup trigger which allows you to choose what unit the concentration is displayed in.

Normally the last value is calculated from the first two, and this is how data is entered into the database. However, if you enter a value into the concentration field, the required mass to achieve this concentration will be calculated and placed into the dilution mass field. This calculation assumes that the dilution volume is that already entered into the volume field.

The dilution section also contains a solution in which the drug is usually diluted. This is entered in the Edit Drug/New Drug screen (see below)

 

Bolus Screen

The bolus screen is in many ways similar to the infusion screen – it is however for bolus doses of drugs rather than continuous infusions.

The following aspects of this screen are identical to that of the infusion screen, and will not be discussed further here: weight field; weight popup trigger; normal ranges; dilution fields; note tab; infusion tab.

Maximum Dose Field

This contains the maximum dose of drug (not on a weight basis) as specified in the drug database. It is a guide only and no attempt is made to alter any calculations or doses based on this figure. If this dose is exceeded, a small “warning” symbol will appear next to the field to indicate this.

Dose Value Popup Triggers
Unlike in the infusion screen, these two triggers are different. The first is a dose per weight (if weight based dosing is selected for this drug – otherwise a red label saying “NOT PER KG” is displayed) while the second is the absolute dose.

The values of these triggers will depend on the mass types and prefixes chosen for the drug. For example, if the mass type is “grams” and the prefix is “milli” the popups will show:

• g/kg
• mg/kg
• mcg/kg
• g
• mg
• mcg

Frequency Field

This shows the frequency per hour the dose can be delivered, as specified in the database. Only two adjacent figures are allowed (eg. 6-8 hourly).

Edit Infusion Screen

This screen is used to edit the infusion data of any existing drugs or enter new drugs into the database. Each separate part of the screen will now be explained in detail.

Category Popup Selector
The right upper corner of the screen contains a standard Palm Popup Category trigger. It allows drugs to be categorised according to function, location, or whatever method the user desires. Simply press on the trigger to select the appropriate category for the drug you are creating or editing.

Drug Name Field
Enter the name for the drug into this field. It can be up to 20 characters long.

Note Tab
Pressing this tab will reveal the note stored for this particular drug, or a blank field if there is no note. Simply enter any information regarding the drug using graffiti or the keyboard. This is for the addition of your own notes on a particular drug. For example, indications, contraindications, interactions, cautions, and so on. This note can be of any size. Form more information, see below.

Prefix Popup Trigger

This chooses the “prefix” of your mass units.

Prefixes available are:

• nano
• micro
• milli
• kilo
• Mega
• Giga

Mass Units Popup Trigger
This chooses the type of mass your drug is. It will automatically change the other popups on the form.
Mass types available are:

·         Grams

·         Units

·         Moles

·         Equivalents

·         Litres

Standard rate Popup Trigger
This popup selector allows you to choose which of the 4 standard rates will be used for the normal range of the drug, and also automatically selected for the first rate field in the main screen.

These four types are:

[mass]/min

[mass]/hr

[mass]/kg/min

[mass]/kg/hr
where [mass] is the chosen mass type with the chosen prefix.

Low Range Field
Enter the low value of the normal range of infusion rates for the drug. The rate type will automatically be set as the "Standard Unit" as described above.

High Range Field
Enter the high value of the normal range of infusion rates for the drug. The rate type will automatically be set as the "Standard Unit" as described above.

Dilution
Enter the mass of drug to be diluted and the volume of the solution it will be diluted into, in mls. The mass can be in the mass units, or mass units per kilogram body weight. The latter will result in an infusion with a variable amount of drug diluted depending on the weight of the patient entered. For example, morphine 1mg/kg in 50mls.

Solution Popup Trigger
Choose which solution, or undiluted drug as your solution.

Concentration PopUp Trigger

Choose the units for the concentration of the solution that will be displayed.

Buttons
Pressing "OK" will make the edited changes to a drug or enter the new drug into the database. If you press "cancel", no changes will be made and the new information will be discarded. You can move from the edit infusion screen to the edit bolus screen using the tabs, without saving or changing any information in the database, but the changes you have made will still be able to be saved when both screens have been completed.

Edit Bolus Screen

The edit bolus screen is similar to the edit infusion screen. There are of course some differences, and only these will be discussed in detail.

Mass Popup Trigger
Use this to choose the mass to be used. It will automatically change the other popups on the form.

Mass Type Popup Trigger
This popup selector allows you to choose which of the mass types will be used.

Weight PopUp Trigger

This trigger determines whether the bolus will be given on a weight (or “per kilogram”) basis.

Low and High Range

Enter the low and high values of the normal range of boluses for the drug. The rate type will automatically be set as the "Standard Unit" as described above.

Maximum Dose

This is a suggested maximum dose for a bolus. Typically weight based doses will not be appropriate for large sized adults, and a maximum dose can be suggested here.

Frequency

Choose an hourly frequency to suggest for the drug bolus. Use “n/a” if this is not appropriate (for example, neuromuscular blockers such as vecuronium).Two adjacent frequencies can be selected (eg 4-6 hourly).

Route
Any of the available routes can be highlighted.

Duration

You can specify the duration over which a bolus should be given in minutes or hours. The rate the infusion should be run at for that duration will then be calculated on the bolus screen.

Note Screen

This screen is used to store notes about drugs in the database.

The screen is a single large field, and has an associated scrollbar when the text contained within the field is larger than can be displayed. Use any normal graffiti commands, including the edit commands and the keyboard, to enter notes.
 
Warning tickbox and bullet button
When the note is being edited, you may check the box marked “Warning symbol” in the lower left. This causes a warning symbol to appear on the infusion or bolus screen.

The purpose of this is to alert the user to the presence of important information in the note that should be reviewed. Pressing on this warning symbol will also take you to the note view.

The “bullet” button inserts a bullet character into the text – useful for highlight paragraphs.

Screen Menu Items

The main screen has 3 menus, “Record”, “Edit” and “Options”, seen by pressing the menu button (not shown here) at the bottom left of the screen, beside the graffiti area. The items available from these menus will now be explained.

Record Menu

· Reload Defaults – reloads the stored dilution values for a given drug – useful if you have altered them and want to return to your usual solution concentration.

· List view – same as pressing the list view arrow – takes you to the list view.

· New Drug – Creates a blank drug and takes you to the edit screen, either infusion or bolus, depending on which screen you were in when you chose the menu item.

· Edit Drug – edit the drug currently being viewed.

· Delete Drug – delete the drug currently being viewed.

· Beam Drug –Beam the drug currently being viewed to another palm running InfusiCalc.

· Send/Beam Category –Sends/Beams all the drugs in the current category. If the Palm receiving them already has this category, the drugs are placed in it; otherwise a new category is created.

· Send/Beam All Drugs – Send/Beam all the drugs on the Palm. They are merged with any drugs on the palm receiving them, and categories are created as necessary.

Options Menu

· Preferences – takes you to the preferences screen.

· Disclaimer – self explanatory.

· Registration –information on how to purchase and register InfusiCalc.

· About InfusiCalc– displays version information.
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Other Aspects

Calculation
The data shown on the screen of InfusiCalc is updated automatically when any variable on the screen is edited. You do not need to press a “calculate” button as in previous versions of the program. At any time, all the data on the screen is accurate, there is never any field “out of step” with the others.

Stored Data
Whenever the application is closed, InfusiCalc stores:

• The current weight
• The current weight unit (pounds or kilograms)
• The current category selected
• The currently selected drug
• Current rates of infusion or bolus

These are used to restore the program to the situation it was in when you last exited the program.

Number Formats
InfusiCalc automatically uses the number format specified in the system preferences.

Error Messages
The fields in the main form are limited to 5 digits with or without a decimal point. If the result of a calculation is outside this range (i.e. more than 99999 or less than 0.0001), an error message will display, and the field will be changed to "-e-" to signify an error result. This will remain this way until some variable change brings the field's contents back within the displayable range.

It may also be seen if a “division by zero” situation arises, such as when the dilution volume is zero. In this case, it is not an error.

Preferences

The preferences screen (available from the menu option in the list screen only) has a few options available to modify the way the program runs.

Use SI Units
Tick this box to use SI units throughout, such as the “micro” symbol and “h” instead of “hrs” or “mL” instead of “mls”.

Volume in CC’s
Use this if you prefer the term “cc” to “mls”.

Dripset

If you give infusions by dripsets which give “drips per minute” rates rather than “mls/hr” you can specify the number of drops/ml for your dripset.

Registration

InfusiCalc is a shareware program. The demo version is fully functional and performs all the functions of the registered version of InfusiCalc. It does not create any annoying messages. It will however, cease to function after twenty one days of use (these need not be consecutive).

The registered version is obviously free from the twenty one day restriction. It also qualifies the purchaser for automatic free upgrades of InfusiCalc as they become available, unless there is some substantial change in form and function of the program.

For information on registering and paying for InfusiCalc, please go to aetherpalm.com .

The payment of the registration fee serves to:

• Encourage me to produce more Palm apps oriented towards critical care/ anaesthesia/ emergency medicine.
• Promote upgrade of InfusiCalc
• Promote the shareware production of software, which is cheap and usually designed with particular users in mind.
• Pay for development costs.
  
  

1. ROMs less than v3.5

The labels on the tabs (“Infusion”, “Bolus” and “Note”) do not show properly in Palm ROMS earlier than 3.3: (models Palm III, Pilot 1000, Pilot 5000, Pilot Professional). If you have a Palm with one of these ROMs, I can send you a version of the program that will run properly. Please email me:

aetherpalm[AT]aetherpalm[DOT]com