Lab Values (US units)
Ranges and what they mean
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If you would rather use a ready-made deck such as Lab Values (US units), we ask you for a small sum in return. For €0.99 once you get 74 flashcards, sorted into 8 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 74
- Categories
- 8
- Price
- €0.99
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What is in this deck
With this deck you learn the reference ranges American laboratories report and what a result outside them means.
A reference range is only half of a lab value. The other half is what to do when the number falls outside it, and that is the half that is asked at the bedside.
74 cards in two halves. First the ranges in the units American laboratories actually report: glucose in mg/dL, not mmol/L; hemoglobin in g/dL; cholesterol in mg/dL. Then the readings that mean something: a potassium of 6.8, a pH of 7.20 with a carbon dioxide of 60, a BUN to creatinine ratio above twenty.
The report's own range wins. Laboratories differ, methods differ, and the range printed beside the result is the one that applies to that sample.
The categories decide what comes up: start with “Blood gas” alone and add the rest when you are ready.
What you learn
- Chemistry, hematology and liver ranges in US units
- Blood gases, and telling the four disorders apart
- Critical values and what is done about them
- Ratios that name a cause: BUN to creatinine, AST to ALT
- The results that mislead: haemolysis, obesity, altitude
The categories
8 categories sort the 74 cards. You can filter by category and take on what is due right now.
- Blood gas
- Cardiac
- Chemistry
- Critical values
- Endocrine
- Hematology
- Lipids
- Liver
What you get
Here are three of the 74 cards you get when you buy the deck.
Question
What is the normal range for Sodium?
Answer
135 to 145 mEq/L
Note
A change of more than 10 in 24 hours risks central pontine myelinolysis.
Question
What is the normal range for Potassium?
Answer
3.5 to 5.0 mEq/L
Note
Above 6.5 is a cardiac emergency; check the ECG before believing a haemolysed sample.
Question
What is the normal range for Chloride?
Answer
98 to 106 mEq/L
Note
Moves with sodium; a gap between them is where the anion gap comes from.
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Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every feature is included. The only thing that costs money is a ready-made deck like this one, €0.99 once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in Lab Values (US units)?
74 cards, sorted into 8 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
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