Welcome to PICU Tools! This freeware program combines a drug database, lab value reference, and several medical calculators for use in the pediatric intensive care environment. Compatibility PICU Tools has been tested on a wide variety of Palm and Handspring Visor devices running PalmOS 3.3 or above, including all Palm III, V and VII models, and Handspring Visor models. PICU Tools requires approximately 285 KB of memory, and may require additional memory if the drug or lab value databases are added to or modified. Introduction With the proliferation of Palm Pilots, Handspring Visors, and the occasional TRG Pro (now HandEra) among attending and resident physicians, transport and nursing personnel, and medical students – and the even greater number of individual Palm applications for medical use – I decided to consolidate many of the most common references and calculators into a single program. Originally a collection of various unassociated programs, PICU Tools has been reworked as an integrated set of tools, each only a screen tap away from any other. Additionally, the drug and lab values databases can be easily modified to include your favorite medications and lab results. Included in PICU Tools are the following: ABG calculator/interpretation aid Body water deficit/excess calculator Drip Rate calculator Drug database Glasgow Coma Scale calculator Guideline editor Lab value database Osmolality calculator Oxygenation Index calculator Peak flow predictor Resuscitation drug dose calculator “Rule of sixes” dosing calculator Sodium correction for hyponatremic seizures Swan-Ganz hemodynamic/oxygenation calculator
Torr calculator (for fixed-wing transports) Installing PICU Tools PICU Tools is distributed in a ZIP archive readable by most Windows 95/98 (and higher) personal computers, or as a single PRC. To install, unzip the zipped archive to retrieve the original PICU Tools.PRC file, then install the PRC as you would any other Palm application (using the Palm Install Tool, or by double-clicking the PICU Tools.PRC file).
1. With your Palm or compatible handheld device in its cradle, run the Palm Desktop or Install Tool (should be available by clicking on [Start], [Programs], [Palm Desktop], and selecting either the “Install Tool” or the “Palm Desktop”.
2. Make sure the correct user is selected (on systems with more than one user). 3. HotSync to transfer the PICU Tools application to your Palm device. 4. Once PICU Tools has been installed on your device, you will initially find it in
the “Unfiled” category. Change categories if you wish to make PICU Tools easier to find.
Running PICU Tools Tap on the PICU Tools icon:
You will be taken to the initial opening screen:
The main screen displays a “waiting room” graphic, tool selector, copyright notice, and (i) “info” icon. The tool and (i) icon at the upper right corner are common to all of the individual tools – tapping the icon will display either a brief description for the current tool, or allow you to obtain more information. The tool-selector assures that any tool is always only a couple taps away.
From the tool list you can select any of the calculators or databases. If you tapped the “Select Tool” area accidentally, tap any other area of the screen to remove the tool list.
Running the individual tools ABG Calculator
The ABG Calculator calculates the effective serum sodium bicarbonate concentration, base excess, alveolar PO2, alveolar-arterial gradient, and PaO2/FiO2 ratio from the FiO2, pH, PaCO2, PaO2, and respiratory quotient (R). The calculator will assume FiO2 of 0.21 and R of 0.8 if these figures are not entered. The interpretation given by the ABG Calculator assumes that the blood gas is arterial (although venous and capillary gases can be used for bicarb and base excess values, as well as interpretation of acid-base status), and that any changes in acid-base status are relatively acute. The calculations and interpretations are based on changes in the carbon dioxide-bicarbonate buffer, and use the Henderson-Hasselbalch equation. This equation is fairly accurate within the common biological pH and PaCO2 ranges, although extremes may be less accurate, and may not agree with values obtained from blood gas instruments. Note that the FiO2, pH, PaCO2, PaO2, and R are in bold text. Throughout PICU Tools, data that is entered by the user will indicated by bold text, while calculations will be displayed in non-bold text.
Body Water Excess/Deficit Calculator
Whether you are dealing with SIADH or hypernatremia, the Body Water calculator will assist in determining the relative amounts of water excess or deficit based on measured and ideal serum sodium (using 60% for body water composition). This calculation gives the amount of water needed to be withheld (in cases of excess water retention in SIADH) or amount of free water deficit (in hypernatremic dehydration) that needs to be included in maintenance and deficit calculations.
Drip Rate Calculator
The Drip Rate Calculator uses the patient’s weight (kg), the amount of drug you want to deliver (in mg/kg/hour), the volume of solution in the bag, and the amount of drug in the bag, and calculates the infusion drip rate. For instance, a 14 kg patient receiving vecuronium at 0.1 mg/kg/hour, with a 100 ml bag containing 100 mg of vecuronium would need a drip rate of 1.4 ml/hour. Be sure to check with the pharmacy that the amount of drug will dissolve in the volume entered, and that the fluid volume is appropriate for your patient.
Drug Information Database
Drug Info is a drug database that can be modified to contain your favorite drugs (not yours, the patient’s!). A number of common medications used in the PICU are included, and the database size is only limited by the amount of memory you have in your database (actually, there’s a 4000-8000 record limit, but I doubt that you will even come close to that many different medications). To search Drug Info, enter the name of the drug (or part of the name) in the “Generic” field, and then tap the “Search” button. If no matches are found, you will get a message to that effect. If only one match is found, it will be listed. If more than one match is found, you will be able to see each match in turn. If more than 20 matches are found, you will only be able to see the first 20. Make your search more specific to eliminate excessively large match lists. Note that ANY text can be searched for, and any match will be shown for text that is found in the generic name, common name, or drug info areas. This makes it easy to search for the antidote for a drug overdose (e.g., searching for acetaminophen will match on n-acetylcysteine, as well as any compound containing acetaminophen). If you already know the exact generic name of the drug, you can enter that in the “Generic” field, then tap the “Show” button to display the drug information. If you’re not sure of the exact spelling, enter the first few letters of the name, and PICU Tools with display the first matching medication.
Drugs can also be searched for using the “List” button, which will bring up a list of medications in the database, sorted alphabetically by generic name. Tap on any name to see the corresponding drug information, or start entering the name in the area supplied under the list. The list of drugs will scroll automatically to point to the closest match.
You will be able to print the drug information to the Memo Pad application, or to PalmPrint (if you have it installed). You can make modifications to the information on any of the existing drugs, or create your own entries. To modify, simply bring up the record for the drug of choice, make your modifications, and then tap the “Save” button. This will give you a warning that the “Record already exists”, with the option to replace the information, or to skip the modification, in case you decide to keep the existing drug information.
GCS Calculator
The GCS Calculator allows you to quickly determine the Glasgow Coma Scale score for infants, children, and older patients. Select the age range “Infant” or “Child and older”, then tap on the “Select” buttons to select your patient’s “Eye Opening”, “Verbal Response”, and “Motor Response”. Once all three are selected, the total GCS will be calculated and displayed.
Guideline Viewer/Editor
The PICU Tools Guidelines viewer/editor allows you to create, edit, and print guidelines for a wide variety of subjects (PICU Tools does not currently ship with any specific guidelines, since these are likely to change). To select a topic, tap its title, then either tap again to bring up the viewer/editor (or tap the "View/Edit" button), or tap the "Delete" button if you wish to remove the guideline from its database. To add a new guideline, tap the "Add Topic" button. Each topic can consist of over 32 thousand characters, allowing you to maintain even large guidelines, and there is no practical limit to the number of guidelines that you can maintain. The guidelines are kept in alphabetic order, making it easy for you to retrieve a guideline on any specific topic.
Lab Values
The Lab Values database is divided into five sections: “Info”, “A-H”, “I-P”, “Q-Z”, and “Fluids”. Tapping on the selector for “Info” gives a brief overview of the available lab tests and references for these tests. The other selectors bring up alphabetic lists of tests and their common values (age adjusted if necessary). Tapping “Fluids” displays data to help interpret the results of CSF, pleural, pericardial, and ascitic fluids. Like the Drug Info database, the Lab Values database can be modified. Make any desired changes, and then tap the “Update” button. Since changes to the Lab Values could potentially be irreversible, you will be warned that the “Record exists”, with the option to update or cancel. Also like the Drug Info database, you can print the Lab Value information to Memo Pad or PalmPrint (if installed).
Sodium Correction (Na Correction/replacement)
The Sodium Correction tool uses the formulas: Na deficit (mEq) = weight * 0.6 * (TargetNa – CurrentNa) Vol 3% NaCl = 2 * Na deficit Where weight is the patient’s weight in kg, and 0.6 is the volume of distribution for sodium chloride. Since 3% used for sodium replacement contains 0.5 mEq sodium per ml, the volume of 3% NaCl required is double the sodium deficit in mEq. This volume of 3% NaCl is infused rapidly to stop seizure activity. Remaining NaCl deficit/fluid overload is corrected gradually (usually over 24-48 hours) once seizure control has been obtained, and serum sodium is at the target value. Most texts suggest correcting hyponatremia to a target value of 125 mEq/L (125 mmol/L), and in practice the actual serum sodium measured after treatment is usually slightly higher than the target value. This may be due to the actual volume of distribution being less than 0.6, or insufficient time for sodium to equilibrate with total body water.
OI Calculator
The OI (Oxygenation Index) calculator uses the mean airway pressure in cmH20 (Paw), FiO2 (as a fraction from 0 – 1), and arterial PaO2 in mmHg to derive the OI using the following equation: OI = Paw*100*FiO2/PaO2 (The astute reader will notice that this is the same as OI = (100*Paw)/(P:F ratio))
Osmolality Calculator
Osmo Calc will calculate the effective serum osmolality by the sodium, glucose, and BUN values. Once calculated, the osmolality can then be compared to the actual osmolality (if measured), displaying the osmolar gap. This is useful in following suspected alcohol or glycol ingestions, or in managing mannitol infusions.
Peak Flow Calculator
The Peak Flow Calculator (actually a predictor, not a calculator) estimates the expected peak expiratory flow rate for children, and uses the data from Polger G, Promedhat V: Pulmonary function testing in children: techniques and standards, Philadelphia, 1971, WB Saunders. This is the same reference used in the Harriet Lane Handbook, and agrees well with published charts. Note that the peak flow predictions using this method may be considerably different than those produced by MedCalc. If in doubt, see which reference agrees most with your institution’s published guidelines.
Resuscitation Medication Calculator
The Resuscitation Medication Calculator calculates appropriate doses for common resuscitation and related medications according to body weight in kilograms, for the following medications: Adenosine Amiodarone Atropine Calcium (Chloride and Gluconate) Dextrose (10% and 25%) Epinephrine Fentanyl Flumazenil Hydrocortisone Ketamine Lidocaine Midazolam Naloxone (low and high doses) Phenytoin Procainamide Sodium Bicarbonate Succinylcholine Thiopental Vecuronium
Reminders are also given for dose administration, as well as suggested "doses" for synchronized cardioversion and defibrillation (in joules/kg). Calculations are also listed for approximate ETT, nasogastric, and chest tube sizes based on the patient's age in years.
Rule of Sixes (inotrope/vasopressor infusion calculator)
The Rule of Sixes Calculator determines the amount of medication to add to a 100 ml amount of fluid based on the patient’s weight, desired medication infusion rate (in mcg/kg/min) and infusion rate (ml/hr - defaults to 1 ml/hr unless you need to modify the concentration of the final solution). This is most useful for infusions of inotropic or vasoactive medications (epinephrine, norepinephrine, isoproterenol, milrinone, inamrinone, etc.). As with the Drip Rate Calculator, check with the pharmacy to assure that the amount of drug calculated will dissolve in the volume of fluid desired (common medications are listed when the calculation is performed). Be careful to take into account the amount of volume being delivered to your patient, as you may need to modify the concentration of the final solution to avoid fluid overload.
Swan-Ganz Calculator
The Swan-Ganz calculator is the most complicated tool in PICU Tools, and has the most crowded screen layout, but with regular use it should become familiar to you. When it is first loaded, the Swan-Ganz Calculator places initial data for weight, height, heart rate, mean arterial pressure, central venous pressure, mean pulmonary artery pressure, pulmonary artery wedge pressure, hemoglobin, FiO2, PaO2, PaCO2, SaO2, PvO2, SvO2, cardiac output, and respiratory quotient. Since the data entry fields are so small in this calculator, there was no room for underlining the fields, so this data was displayed to show where the fields are. Change the data according to your patient’s own data. Any data used for calculations will be stored, and recalled the next time you run the Swan-Ganz calculator. Once all the data are entered, tapping the “Calc” button will store the patient’s data, and perform the hemodynamic and oxygenation calculations. If any data is missing, only those calculations that can be performed will display data, other fields will have “n/a” displayed. The P/F ratio will also be displayed (if available), and you will be given the option to print the results of the calculations to Memo Pad or PalmPrint (if installed).
Tapping the (i) information icon will allow you to view more information, including the abbreviations, formulas, and units used in the calculations. Tapping "Continue" will bring you back to the original Swan-Ganz Calculator screen.
Torr Calculator
The Torr Calculator was written to allow the calculation of alveolar O2 (PAO2) given the current barometric pressure in torr, then the calculation of the same information at any given altitude (from 3,000-40,000 feet), along with the FiO2 that would be required to maintain the same alveolar PO2 as the original altitude. This will be most useful for patients who will be transported by fixed wing, or who will be traveling between two areas with significantly different atmospheric pressures. For instance, a patient at sea level with current torr 760, FiO2 0.40, and PaCO2 of 45 and a respiratory quotient of 0.8 will have an alveolar PO2 of approximately 229 mmHg. If taken on fixed wing transport with a cabin pressure equivalent to an altitude of 5000 feet (632 torr, 0.83 atmospheres pressure), his alveolar PAO2 will drop to 177, and he will require an FiO2 of 0.49 to maintain his original PAO2.
Exiting PICU Tools To stop running PICU Tools, simply turn the Palm device off, tap the “Launcher” soft key (looks like a small house), or press any of the application buttons at the bottom of the device. Note that pressing the [Up] or [Down] arrows will scroll any scrollable fields on the current PICU Tool screen, but will not exit the program. Unlike some Palm programs, PICU Tools does not remember its last used screen. If you have made any modifications to data or calculations, save the changes, or print your information prior to exiting PICU Tools. Printing from PICU Tools Several of the calculators and databases in PICU Tools can print directly to the Memo Pad application or to printers using PalmPrint from Steven’s Creek Software at www.stevenscreek.com. Many IR-enabled printers are supported, and there are IR adapters for use with other printers. Bug reports, function requests, and feedback Your feedback is essential in making PICU Tools a truly useful reference for medical personnel! Please send any bug reports, function requests, or feedback to: [email protected]. Not only will this provide me a way to fix any bugs, but will also allow me to send you the revised application. *** End of documentation for PICU Tools ***
