Normal sodium, potassium and serum osmolality values mnemonic

Hello!

In my last post, I helped you guys remember normal arterial blood gas values. Now, we are going to remember a few electrolytes. Yaay! :D


Let's start with pH, as you all know, normal pH is 7.35 - 7.45

Remove the decimal, change 7 to 1 and you get normal sodium value, 135 - 145

Remove the 1, add a decimal and you get the normal potassium value, 3.5 - 4.5

From the sodium value, go 1, 2, 3, +4, 5 to get the lower limit of the normal serum osmolality.

1 3 5
 +4
2 7 5

Add 20 and you get the upper limit, that is, 295

The image will help you visualize it better:

Normal sodium, potassium and serum osmolality values mnemonic

So to summarize:
Sodium level 135 - 145 mEq/L
Potassium level 3.5 - 5.0 mEq/L
Osmolality (serum) 275 - 295 mOsmol/kg

That's all!

Why do I need to memorize the values? So that you can glance at the report and know what is going on with the patient and look all cool instead of referring the normal values. Also, saves time in exams :)

-IkaN

Related post: Normal arterial blood gas values and serum electrolytes mnemonic