Disorders of potassium - Hyperkalaemia - Hypokalaemia

1. Disorders of Potassium
-M.Mohan
-B.Sc Renal Dialysis
-P.E.S Institute

2. CONTENTS
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03
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Introduction
Causes
Investigation
Management

3. What is potassium??
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Potassium is a mineral that your body needs to work properly. It is a type
of electrolyte. It helps your nerves to function and muscles to contract. It
helps your heartbeat stay regular. It also helps move nutrients into cells
and waste products out of cells. A diet rich in potassium helps to offset
some of sodium's harmful effects on blood pressure.
Many people get all the potassium they need from what they eat and
drink. Sources of potassium in the diet include:
Leafy greens, such as spinach and collards
Fruit such as grapes and blackberries
Root vegetables, such as carrots and potatoes
Citrus fruits, such as oranges and grapefruit
Your kidneys help to keep the right amount of potassium in your body. If
you have chronic kidney disease, your kidneys may not remove extra
potassium from the blood. Some medicines also can raise your
potassium level. You may need a special diet to lower the amount of
potassium that you eat.

4. Introduction:-
- K + is the second most abundant cation in the body
(3.5mol).
-Dietary K + amounts to 80 – 150mmol/day. Only
around 65mmol is present in the ECF, with the great
majority (98%) found within cells in muscle (and, to a
lesser extent, liver, red cells, and bone
-Total body K + balance is regulated by renal
excretion: K + is freely filtered at the glomerulus
(700mmol/day) and is reabsorbed by the PCT
(75%), the loop of Henle (15%), and the A-intercalated
cells of the collecting duct.

5. Conti......
- K + secretion is responsible for most urinary potassium
loss and is tightly controlled by aldosterone in the DCT
and the principal cells of the collecting duct.
-In health, around 1 – 1.5mmol/kg/day is excreted in
urine, with a small fraction ( 7- 10mmol) in faeces
-Obligate urinary K + loss (10 – 15mmol/day) will always
occur, no matter how low the serum K +
-Aldosterone secretion is increased directly by
hyperkalaemia (and hypovolaemia) and suppressed by
hypokalaemia controlling K + in the normal range (3.5 –
5.0mmol/L).

6. Hyperkalemia:-
-True hyperkalaemia is either due to increased release from
cells or decreased excretion by the kidney. Since the release
of important trials using spironolactone or eplerenone (in
addition to ACE inhibitors) in the treatment of heart failure,
dangerous hyperkalaemia has become more common in
those with better renal function

7. - Increased K + is often spurious: always recheck result.
Traumatic venepuncture leads to cellular K + leakage and false
hyperkalaemia.
-This leads to 1 – 2mmol/L rise in the apparent K +. Fine-bore
needles, tourniquets, and fi st clenching can all induce
mechanical release of K + from cells, as can cold temperature.
Psudohypokalemia:-

8. Common causes include:-
•CKD
•K + -rich diets (bananas, other fruits) with CKD.
•Drug-induced (esp. combinations of the following):
-ACE inhibitors/ARB.
-K + -sparing diuretics (spironolactone, eplerenone, amiloride).
-NSAIDs.
-Heparin and LMW heparins (inhibit normal aldosterone release).
- Ciclosporin.
-High-dose trimethoprim.
- Digoxin toxicity (but not therapeutic levels of digoxin).
-B-blockers.

9. Conti......
• Hypoaldosteronism
•Addison’s.
•Increased release from cells:
-Acidosis (lactic).
-Insulin defi ciency (DKA).
- strenuous exercise, or tumour lysis.
-Massive haemolysis.
-Succinylcholine use.

10. Conti......
Other rare causes
-Hyperkalaemic periodic paralysis: mutations in skeletal Na +
channel
-Type 1 pseudohypoaldosteronsim: presents in infancy

11. Hypokalaemia;-
-One of the most common electrolyte
abnormalities seen, esp. in patients on
diuretics
-Although K + of 3 – 3.5mmol/L is generally
well tolerated hypokalaemia of <2.5mmol/L
can be life-threatening (esp. in the presence
of digitalis(used to treat heart failure)

12. Causes:-
Causes
• Inadequate intake <25mmol/day (either dietary or IV).
•Increased gut losses:
-Vomiting
-Diarrhoea or laxative abuse.
-Zollinger – Ellison syndrome(a rare condition in which one or more tumors .
form in your pancreas or the upper part of your duodenum
• Redistribution into cells:
-B-agonism (any cause of ⬆sympathetic drive, e.g. delirium tremens).
-B-agonist drugs (bronchodilators, decongestants)
-Insulin, theophylline, or caffeine (activate Na + /K + -ATPase pump).
• Alkalosis.
• Vigorous exercise

13. Contin..,...,
•-1°hyperaldosteronism: adrenal adenoma (Conn’s
syndrome), bilateral
adrenal hyperplasia — plasma aldosterone:renin ratio
-Renin-secreting tumours ( i BP in the young)
-Cushing’s disease.(Cushing's syndrome is a hormonal
disorder caused by high levels of the hormone
cortisol(ACTHACTH) in your body)
-2° hyperaldosteronism(Liver failure, heart failure,
nephrotic syndrome)

14. Conti....
-Renal losses:
• Diuretics (esp. thiazides, loops), including abuse of
diuretics.
• Acquired renal tubular disease
-Other drugs:
• Amphotericin and aminoglycosides (tubular toxicity).
• Glucocorticoids (esp. at high dose) or
mineralocorticids.
-Hypomagnesaemia

15. Symptoms and signs:-
-See previous list of causes for specific associations —
usually picked up on U&E.
-Take a full drug history, particularly for diuretics.
Exclude diarrhoea
-Fatigue
-constipation
- proximal muscle weakness, and ⬇tone
-Cardiac arrhythmias, esp. if underlying heart disease
-⬇urinary concentrating ability
-Increased blood pressure

16. Investigations:-
-U&E
*Mg+2
*calculate the anion gap(measures the difference
between the negatively charged and positively
charged electrolytes in your blood. If the anion gap is
too high, your blood is more acidic than normal)
- Either perform 24-hour urinary K + or do spot u-K +
and u-Cr.
-Calculate the urinary K/Cr ratio (KCR)
-Digoxin level if on drug.
-If 24-hour u-K + <15mmol/L, losses are EXTRARENAL.

17. -depending on the KCR, focus attention as shown in Table
- Check the ECG: small T waves, U wave (after T), PR interval ⬆,
ST segments ⬇

18. Treatment:-
-Is the patient on digoxin? Will potentiate digoxin’s
arrhythmogenicity. -Note that diuretic-induced
hypokalaemia is exacerbated if dietary Na +intake is
high. Always aim to treat the underlying cause over
time.
Mild (>2.5mmol/L):
-Oral slow-release potassium chloride 50 –
150mmol/day in divided
doses
•⬆dietary K + and ? switch to K + -sparing diuretic.

19. Contin....
-Severe or symptomatic hypokalaemia (K
<2.5mmol/L, arrhythmias,
liver failure, or extreme weakness)
• Cardiac monitor.
• Check Mg 2+ , and correct if need be .
• Avoid glucose-containing solutions or sodium
bicarbonate.
• IV 0.9% saline 1L with 20 – 40mmol KCl at no more
than 10-20mmol KCl/h through peripheral cannula.
If ⬇K + with hyperchloraemic acidosis, avoid 0.9%
saline, and rather use KCl

20. Contin....
• In volume-restricted patients KCl can
be given into a central vein as 20 –
40mmol/100mL 0.9% saline (NOT
glucose, risk of hypokalaemia) at not >
40mmol/h using a volumetric pump

21. Potassium in dialysis:-
-Potassium is a mineral that controls nerve and muscle
function. The heart beats at a normal rhythm because of
potassium. Potassium is also necessary for maintaining
fluid and electrolyte balance and pH level.
Low potassium:-
Potassium comes from the foods we eat. Healthy kidneys
remove excess potassium in the urine to help maintain
normal levels in the blood.
-Because most foods have potassium, low potassium
(hypokalemia) is uncommon in people who eat a healthy
diet.

22. Hyperkalaemia
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When kidneys fail they can no longer remove excess
potassium, so the level builds up in the body. High
potassium in the blood is called hyperkalemia, which
may occur in people with advanced stages of chronic
kidney disease (CKD)
For people with stage 5 CKD (also known as end stage
kidney disease or ESKD), dialysis is necessary to help
regulate potassium. Between dialysis treatments,
however, potassium levels rise and high-potassium
foods must be limited.

23. Effects of hyperkalaemia:-
-Nausea
-Feeling tired or weakness
-Muscle pain or Muscle cramps
-Trouble breathing
-,unusual heartbeat,
-chest pain

24. Consequences of potassium:-
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Managing high potassium is important if
you want to protect heart function
• Having too much potassium in your blood
can be dangerous. High potassium can even
cause a heart attack or death!

25. High potassium foods :-
Foods:-
-Banaana 🍌🍌
-kiwi 🥝🥝🥝
-Mango 🥭🥭🥭🥭
-oranges 🍊🍊🍊
- Papaya
Vegetables:-
- Dried beans
- Pumpkins🎃🎃🎃
- Potatoes 🥔🥔🥔
- Sweet potato
- Tomatoes 🍅🍅🍅

26. Low potassium foods :-
• Foods:-
-Apples🍎🍎🍎
-Berries
-Grapes 🍇🍇🍇
- Lemon 🍋🍋🍋
- Pine apple
- watermelon🍉🍉
Vejitables:-
- Carrot🥕🥕🥕
-Cabbage
-Cauliflower
-Green beans
- Onion🧅🧅

27. Thank you for
listening to