Technology: friend and foe.
Recently, I was making a small purchase of stickers for my 11 year old. The cashier rang it up to be $1.36. I handed her a twenty dollar bill. As her cash register flashed the amount of change I was due--$18.64--I dipped into my wallet for the odd penny. As I handed her the penny she looked stunned. I instantly recognized her confusion and muttered, "$18.65". "Thanks!" she breathed in relief.
Now I turn to a mental recollection of my 8 year old learning to make change for a math assignment. Yes, we still teach children how to calculate. But does the technology make us lazy? Do our mental calculating muscles become atrophied as we integrate technology into our every day lives?
I think we're safe as long as we keep our perspective. It's not the process of calculating that is important, but rather what we do with the data we produce. Calculators free us up to perform the task of greater importance; interpreting and applying data.
Relying on technology can be flawed. Flaws are the result of "human error". You can have the fanciest calculator in the world; the human operator is the key to a successful outcome. Garbage in, garbage out (humour) Garbage In, Garbage Out - (GIGO) /gi:'goh/ Wilf Hey's maxim expressing the fact that computers, unlike humans, will unquestioningly process nonsensical input data and produce nonsensical output. . The operator must ensure that the data going in AND the data coming out is valid.
In Respiratory Care we went from being mechanics of unique machinery (remember hot pots and plumbing clamps?) to software operators with sophisticated microprocessors. The human being integrates the ventilator with the patient. The technology provides us, the clinician, with a greater amount of data. We must validate and apply that data to the clinical situation of our patient.
Let's look at sources on the Internet for medical calculators. I searched on-line to see what the tech geeks had come up with as far as calculators. Respiratory Care is fraught with calculations, from tanks, to blood gases, to hemodynamics hemodynamics /he·mo·dy·nam·ics/ (-di-nam´iks) the study of the movements of blood and of the forces concerned.hemodynam´ic
If you search for "medical calculators" you will get most of the better sites to come up. I've chosen some of the better sites and will list them here with a quick description. Educators and students will love these. Patient educators as well will like some of the "score" calculators. Technology can only produce good result with good input. Therefore, all of these sites display a disclaimer. Before relying on a calculator that is new to you, verify that the results it is producing are accurate. Example Disclaimer: "All calculations must be confirmed before use. The authors make no claims of the accuracy of the information contained herein; and these suggested doses/values are not a substitute for clinical judgment."
Tucows & Freeware Palm -- If you have a palm pilot and would like to try some fun and handy freeware/shareware like the "ABG ABG
arterial blood gas
ABG 1. Arterial blood gas 2. Axiobuccogingival–dentistry Decoder" that I mentioned I would recommend visiting www.tucows.com. They have a tank calculator, dosage calculators, BMI BMI body mass index.
body mass index
Body mass index (BMI)
A measurement that has replaced weight as the preferred determinant of obesity. calculator and others, including the "MD ABG" designed to do everything from simple single acid/base disorders to the complex triple acid/base nightmares.
Another program that includes 82 calculations, pulmonary and cardiac included, is at the following link: www.freewarepalm.com/medical/icumath.shtml
Pediatric pediatric /pe·di·at·ric/ (pe?de-at´rik) pertaining to the health of children.
Of or relating to pediatrics. Critical Care Medicine at Cornell University has conversion calculators, respiratory calculators and metabolic calculators (as well as dosage calculators). I like these because they also give a narrative explanation to help interpret results and they show the actual calculation formula used by the calculator. For example, here is the explanation for A-a gradient: "High gradients result from impaired diffusion or, more commonly, by ventilation-perfusion inequality of the "shunting" variety. A normal A-a gradient is less than 10 torr torr (tōr),
n a unit of pressure equivalent to 0.001316 atmosphere; named after the physicist Torricelli. Also called
mm Hg. . The age (years) / 4 + 4 is another conservative estimate of a normal gradient. The calculations assume 100% humidity at sea level and a respiratory quotient of 0.8, using the alveolar gas equation The alveolar pO2 is not routinely measured but is calculated from blood gas measurements by the Alveolar gas equation: to determine PAO PAO Peak acid output, see there 2: PAO2 = (FiO2 * (760 - 47)) - (PaCO2 / 0.8) A-a gradient = PAO2 - PaO2 http://www-users.med.cornell.edu/~spon/picu/calc/medcalc.htm
Internal Medicine at Medical College of Wisconsin has a small list of calculators. Some of the cardiac calculators have an explanation. The calculators are: A-a Gradient, Anion Gap, BSA/BMI, Estimated creatinine clearance, Fractional Excretion of Sodium, Heart Disease Risk, LDL Cholesterol Goal Level, Ingested Substance Blood Level, Serum Osmolality osmolality /os·mo·lal·i·ty/ (oz?mo-lal´it-e) the concentration of a solution in terms of osmoles of solute per kilogram of solvent.
n. , Temperature Conversion (F-C). http://www.intmed.mcw.edu/clincalc.html
MediCalc 3000 is a commercial site and will only provide you with a sampling of calculators for free. You must pay for the rest. Once at the site click on "Search by Specialty" and you will be taken to the list of calculators. They have some that are different than the standard calculators like "Pneumothorax pneumothorax (nmōthôr`ăks), collapse of a lung with escape of air into the pleural cavity between the lung and the chest wall. The cause may be traumatic (e.g. Degree of Collapse" for example. http://medcalc3000.com/
MedStudents.com is a site designed by Richard Toptani, an Internal Medicine Resident at Iowa University. There are alot of hemodynamic he·mo·dy·nam·ics
n. (used with a sing. verb)
The study of the forces involved in the circulation of blood.
he formulas. Each calculator includes the formula. http://www.medstudents.com.br/calculat/index2.htm
The Reference Desk has calculators/simulators useful for students. www.martindalecenter.com/Calculators1B_3_MedPZ.html
n.pr See Agency for Healthcare Research and Quality. -- Agency for Healthcare Research and Quality--I liked the pneumonia severity index The pneumonia severity index is a clinical prediction rule that medical practitioners can use to calculate the probability of morbidity and mortality among patients with community acquired pneumonia. calculator at this site. This is a direct link to the calculator. http://pda.ahrq.gov/clinic/psi/psicalc.asp
EMedicine.com has calculators but also "scores" for things like croup croup (krp), acute obstructive laryngitis in young children, usually between the ages of three and six. . www.emedicine.com/splash/shared/etools/index.htm
Recently, I was discussing a blood gas result with one of my coworkers. I thought we might calculate the A-a gradient. As I reached w-a-a-a-y back in my brain to drag out the Henderson-Hasselbach equation, I goaded my coworker, "FIO2 times barometric pressure minus......" He rolled his eyes but once my calculation was complete we discussed what might be causing this huge A-a gradient in our ventilated ven·ti·late
tr.v. ven·ti·lat·ed, ven·ti·lat·ing, ven·ti·lates
1. To admit fresh air into (a mine, for example) to replace stale or noxious air.
2. patient. My coworker is a great example of what really counts in a therapist. Recalling rote formulas is not what's important, rather it's being able to understand and apply the information to better serve the patient. Technology keeps adding clinical tools to our arsenal. Let's use them.
by Lisa Rapple M.Ed RRT RRT Rapid Response Team
RRT Registered Respiratory Therapist
RRT Renal Replacement Therapy
RRT Regional Response Team
RRT Right Side (philately)
RRT Relative Retention Time
RRT Round Robin Test
RRT Rating Region Table