wtfness x2

[mayoraasei]

Okay, how is one supposed to study when the questions contradict each other?

Q1: Which of the following causes hyponatraemia and hypokalaemia?
Ans: Vomiting

Q2: Causes of hyponatraemia include vomiting, true or false?
Ans: FALSE. Gastric secretions are low in sodium.

.......WWWWWWWTTTTTTTFFFFFFFFFFF.

My notes agree with the 2nd statement, which is why the first question totally screwed me up.

Apparently diarrhoea is not a cause of hyponatraemia??!! WTF?!!! Using "MOST" diarrhoea is caused by water loss only is not a frigging good excuse! So what happens to the SOME diarrhoea that's caused by massive chlorine dumping accompanied by sodium and water flow into the lumen??!??! As well as inability to absorb ions because of intestinal disturbance/damage to brush border/whatever??!?! That's not A CAUSE?!?!

UGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHH. I HATE MULTIPLE CHOICE. YOU CAN'T EVEN JUSTIFY YOURSELF.

Comments

[luna-rainbow.livejournal.com]

Ah, thanks. I think what's bothering me is that both answers are correct, because there's a huge unwritten qualifier. You're more likely to get hypokalaemia before hyponatraemia right? And you'd have to have vomited up copious amounts to get hyponatraemic. So in essence they're both correct...

I keep thinking gastric Na is very low because of all the active uptake, whereas there's bound to be some free potassium because of potassium channels that allow potassium into the lumen to drive the K/H-exchanger. Gah @__@