Flashcards in Session 6 - Notes (SS only, add group work post-resp) Deck (7)
Would an impaired ability of the kidney to reabsorb Na+ ions cause hypokalaemia? (Bartters syndrome)
Yes, mimics the effect of loop diuretics by downregulating NaKCC in TAL
Would use of ACE inhibitors cause hypokalaemia?
ACE inhibitors will result in depressed aldosterone secretion, hence K+
Why should late distal diuretics not be administered in parallel with ACE inhibitors?
Late distal diuretics also dispose towards hyperkalaemia, and this is why these drugs
must never be administered in parallel
Would Conn’s syndrome (primary hyperaldosteronism), most commonly arising from
adrenal adenoma cause hyper/hypokalaemia?
Conn's syndrome may be associated with hypokalaemia due to enhanced K+
Would chronic laxative abuse cause hypokalaemia?
Chronic laxative abuse, like diarrhoea, causes hypokalaemia. This is because the high
intestinal fluid content will lead to the K+
within it being relatively dilute. One of the
factors affecting the rate of washout of K+
from cells lining the intestinal tract will be
the intra-/extra-cellular K+
concentration gradient. When this is increased, as in
laxative abuse, more cellular K+
will lost from these cells.
Heavy exercise causes transient hyperkalaemia for 2 reasons. Firstly, K+
released into the plasma from mechanically ruptured red cells. Secondly, many cell
types, including myocytes, contain ATP sensitive K+
channels; these are normally
blocked by ATP. As ATP is depleted, these channels become unblocked and K+
out. This has a beneficial effect, because K+
ions are vasodilators, and blood flow to
exercising muscle is thus increased.