Lecture 9
Definition
 Serum Na concentration above reference range. (135-
145 mmol/L).
 Water loss
 Sodium gain
Water loss
 Pure water loss
 Decreased intake (elderly, unconscious)
 Excessive loss (decreased AVP secretion diabetes
inspidus, nephrogenic)
 Water and sodium loss
 Water loss exceeds sodium loss
 Osmotic diuresis (DM, excessive sweating or diarrhoea)
Sodium gain
(salt poisoning)
 Sodium bicarbonate (for correction of acidosis)
 Near drowning in salt water
 Infants fed on high salt diet (1 tbs of salt raises upto 70
mmol/L of sodium.
 Primary hyperaldosteronism
 Cushing’s disease. (150 mmol/L)
Clinical Manifestations
 Confusion
 Neuromuscular excitability
 Hyperreflexia
 Seizures
 coma
Treatment
 Free water 5% dextrose
 Diuretics or natriuresis
Other osmolality diordres
 Increased urea in renal diseases
 Hyperglycemia
 Ethanol
 Osmolal gap
 Common cause is presence of ethanol
 Comatosed patients
Hyperkalemia
 Important IC electrolyte
 Maintain resting membrane potential of the cells like
nerve and muscle cells.
 Heart arrythmias
 3.5- 5.5 mmol/L
 30 -100 mmol/L is intake
 5 mmol loss through GIT
 20-100 mmol/L through kidneys
 ˃ 7 mmol/L is life threatening
 Cardiac arrest
 ECG changes
 Muscle weakness
 Parsthesias
Causes of hyperkalemia
 Increased intake
 Redistribution
 Decreased excretion
Increased intake
 Patients with impaired renal functions
 Drugs as potassium salts
 Intra venous (20 mmol/hr)
 Blood products
Redistribution out of cell
 Metabolic acidosis
 Potassium release from damaged cells
 Insulin deficiency (insulin stimulates cellular uptake
of potassium)
 Hyperkalemic periodic paralysis
 Rare familial disorder autosomal dominance
 Recurrent attacks of muscle weakness or paralysis
 Rest after exercise
 Pseudohyperkalemis
Pseudohyperkalemia
 Sampling errors
 Hemolysis (rbc, wbc and platlets)
 Check potassium in serum and plasma
Decreased excretion
 Renal failure
 Potassium can not be excreted out when GFR is low
 Hypoaldosteronism
 ACE inhibitors
 Potassium sparing diuretics
Treatment
 Insulin infused along with glucose
 Calcium gluconate
 Cation exchage resins orally
 Dialysis in refractory hyperkalemia