This document discusses electrolyte disturbances, focusing on sodium, potassium, hyponatremia, hypernatremia, and diabetes insipidus. Some key points:
- Sodium is the major ion in extracellular fluid and regulates plasma volume, membrane potential, and glucose/amino acid transport. Renal excretion tightly regulates sodium levels.
- Hyponatremia is classified based on serum osmolality as normal, high, or low. Causes and management depend on volume status and underlying condition. Chronic hyponatremia requires slow correction to avoid osmotic demyelination syndrome.
- Hypernatremia results from water loss or sodium gain. It is classified based
This lecture is based on National guidelines(Sri Lanka) and guidelines by NHS UK. all the materials used to prepare the lecture are trusted and high in quality. also the books referred are internationally recognized. both hyper and hypokalemia management included in the lecture. lecture is free and you can even download. i kept no copy rights. i appreciate your support, comments and suggestions. also i would be grateful if you can make these lectures popular. wishing your success.
This lecture is based on National guidelines(Sri Lanka) and guidelines by NHS UK. all the materials used to prepare the lecture are trusted and high in quality. also the books referred are internationally recognized. both hyper and hypokalemia management included in the lecture. lecture is free and you can even download. i kept no copy rights. i appreciate your support, comments and suggestions. also i would be grateful if you can make these lectures popular. wishing your success.
Establishing and maintaining normal extracellular volume (ECV) is required to achieve normotension. The achievement of an optimal fluid status, as expressed by "dry weight" (DW), should allow for controlling blood pressure (BP) in the large majority of HD patients
Establishing and maintaining normal extracellular volume (ECV) is required to achieve normotension. The achievement of an optimal fluid status, as expressed by "dry weight" (DW), should allow for controlling blood pressure (BP) in the large majority of HD patients
Functional Anatomy of the Spine for Anesthesiaperezjohnangelo
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Sodium is necessary for the body to maintain fluid balance and is critical for normal body function. It also helps to regulate nerve function and muscle contraction.
Hyponatremia and Hyponatremia.
7. • Renal excretion of sodium is adjusted to
equal the amount ingested.
• Urine sodium output 1 - 400 mEq/day
• The normal is 90 mEq/d
8. • In the kidney 96-99 % of the filtered
sodium is reabsorbed
– 67% in PCT by active process
– 25% in thick ascending loop of Henel
passively (loop diuretics acted upon)
– 5% in DCT & 3% in CD in exchange with K &
Cl (controlled by aldosteron).
10. Hyponatremia
• Hyponatremia means serum sodium less
than 130 mEq/L
Less than 130 Mild
• Less than 125 Moderate
• Less than 115 Severe
11. • No linear correlation between degree of
hyponatremia and symptoms.
• Symptoms depend upon the rapidity of
occurrence of hyponatremia.
12. Because of difference between the
regulation of total body volume and
sodium concentration, it is possible to
have hypo- or hypernatremia in face of
hypo-, hyper-, or euvolemia.
13. Classification of Hyponatremia
I- Hyponatremia with normal serum
osmolality
II- Hyponatremia with high serum osmolality
III- Hyponatremia with low serum osmolality
14. I-Hyponatremia with normal serum
osmolality
• S. Osmolality: 280-295 mOsm/kg water
• Called Pseudohyponatremia
• Causes:
– 1- Hyperlipidemia (every 4-6 gm/L increase in
lipids leading to 1mEq/L decrease in sodium.
– 2- Hyperproteinemia e.g. multiple myeloma
(every 10gm/dl increase leading to 1mEq/L
decrease in serum sodium).
15. II-Hyponatremia with High Serum
Osmolality
S. Osmolality: > 295mosm/kg water
• Called Hypertonic Hyponatremia
Caused by increase impermeant solutes
replacing sodium in the blood
16. • Causes:
1-Non sodium solutes e.g.
glucose, mannitol, and some toxins
(ethanol & urea).
2- Renal failure due to impaired water
excretion.
17. Management of Hyponatremia with
normal & High S. Osmolality
- Restoration of volume and free water deficit
- Treatment of non-sodium salts e.g. toxins
- Treatment of hyperglycemia or mannitol level
- Treatment of hyperlipidemia or
hyperprotenemia.
18. III-Hyponatremia with
Hypoosmolality
• S. Osmolality : < 280 mosm/kg water
• It is the most common type
• It means that free water intake more than
water loss
19. Types of Hyponatremia with Hypo-
osmolality
• Based on clinical assessment of total body
water and sodium content it is classified
into:
1. Hypovolemic hypoosmolar hyponatremia
2. Hypervolemic hypoosmolar
hyponatremia
3. Euvolemic hypoosmolar hyponatremia
23. Management of Hypovolemic
Hypoosmolar Hyponatremia
• - Replace the volume depletion to depress
ADH by isotonic crystalloid, or colloids and
blood if not enough.
• -Replace free water with sodium by Water
restriction and Furosemide
• Replace urine output by isotonic or
hypertonic saline
24. 2- Hypervolemic Hypoosmolar
Hyponatremia
• It is called dilutional hyponatremia
• Causes:
• CHF
• Liver cirrhosis
• Nephrotic syndrome
25. Manifestations of Hypervolemic
Hypoosmolar Hyponatremia
• Total body water increased and the patient
is edematous but
• The effective circulatory volume is low.
• Urine sodium < 15 mEq/L
• Urine osmolality > 400 mosm/kg w
26. Management of Hypervolemic
Hypoosmolar Hyponatremia
• The aim of management is to improve
• The effective circulating volume
• Renal function
• Cardiac function
• Distal tubular delivery of sodium
*Combination of furosemide & ACE
Inhibitor.
27. 3-Euvolemic Hypoosmolar
Hyponatremia
* Syndrome of inappropriate ADH secretion
• Excess ADH secretion
• Secretion stimulated by non-osmotic,
non-volumic factors e.g.:
– Emotional stress
– Endocrine disorders
– CNS diseases
– Excess hypotonic fluids
– Drugs e.g. NSAID & Carbamezapine
• Urine Na > 30mEq/L, U. Osm > 400mosm
28. Management of Syndrome of
inappropriate ADH secretion
• Treatment of the cause e.g. brain tumor
resection
• Free water restriction
• Furosemide to get –ve water balance
• Replace fluid by isotonic or hypertonic
saline
• Measure serum sodium every 6:12 h.
29. • * Water intoxication: e.g.
• Psychosis
• Heavy beer drinking
• Absorption of hypoosmolar fluids
during prostate resection.
• Urine osmolality < 100 mosm/kg w
• Treated by water restriction
30. General Manifestations of
Hyponatremia
• Serum osmolality and cellular dehydration
are the main insult done
• CNS cells are the most affected by
changes in osmolality.
• CNS compensate for slow changes in
osmolality affected severely in acute
changes.
31. General Manifestations of
Hyponatremia
• In acute hyponatremia:
• -CNS manifestations:
• begin by lethargy & confusion up to
seizures, cerebral edema & coma
• GI symptoms
• Muscle cramps & weakness
33. Management Based on:
*Treatment of the cause
*Restoration of serum sodium
concentration
*Normalization of serum osmolality
34. Correction of Serum Sodium
Acute changes in sodium concentration
should be treated rapidly, but
• Chronic changes should be treated more
slowly.
35. In acute hyponatremia (<2 days):
Correct by no faster than 1 : 2 mMol/L/h
Serum sodium not increased more than 130
mEq/L and avoid hypernatremia
In presence of seizures or increase ICP the
correction could be in 3 :4 mMol/L in the
first hour or even 8 mMol/L
36. In chronic hyponatremia:
Correct by less than 12 mMol/L/day
The rapid correction may leads to:
Osmotic Demyelination Syndrome
Severe neurological deterioration after one
to several days of rapid correction.
37. • The amount of sodium required to increase
serum sodium concentration is calculated
as the equation:
• Na required=
(Desired Na – Present Na) * TB Water
• TB Water =
• BW * 0.6 in male (0.5 in female)
38. • The desired sodium should not exceed
130mEq/L
• Hypertonic saline used only in severe
hyponatremia
• Hypertonic saline should be stopped when:
• Pt become asyptomatic
• Plasma sodium increased by 20 mmol/L
• Plasma sodium reached to 120:125mmol/L
44. I-Hypernatremia with hypovolemia
• Causes:
• 1-Renal water loss e.g.
• Osmotic diuretics in excess
• Tubular renal disease
• Adrenal failure
• Impaired response to ADH & DI
– U Na>20 mMol/L
– U Osm<300:400 mOsm/kg water
45. • 2- Non-renal water loss e.g.
• GI loss e.g. diarrhea
• Skin loss, severe sweating
• Peritoneal dialysis
– U Na < 15 mMol/L
– U Osm > 400 mOsm/kg water
46. II-Hypernatremia with hypervolemia
• Causes:
• 1- Iatrogenic (Na containing compounds)
• 2- Mineralocorticoid in excess e.g.
• Aldosteronism
• Cushing disease
• CAH
– U Na >20 mMol/L
– U Osm >300 mOsm/kg water
47. III- Hypernatremia with euvolemia
• Causes:
• 1-Renal water loss e.g.
• DI
• Renal disease
• Diuretics
– U Na variable
– U Osm <290 mOsm/kg water
48. • 2- Non renal water loss e.g.
• Diarrhea
• Fever
– U Na variable
– U Osm > 400 mOsm/kg water
49. Diabetes Insipidus
• I- Central DI
• Idiopathic DI
• Following head trauma
• Neurological disease
51. Clinical Features of Hypernatremia
• Neurological features:
– Begin by irritability, to focal deficit up to
cerebral dehydration & hemorrhage
• Cardiovascular features
– Manifestations of volume depletion up to
shock
• Renal features
– Polyuria or oliguria up to renal insufficiency
52. Management of Hypernatremia
• Acute hypernatremia treated rapidly
• While chronic state should be treated
slowly to avoid neurological insults as
seizures and cerebral edema
• Correction should not exceed 2mMol/L/h
53. Management of Hypernatremia:
1- Treatment of the underlying cause
2- Volume repletion with isotonic saline
Hypotonic fluid used after volume repletion
Water deficit replaced over 24 : 48 h
3- Sodium overload :
Removed by loop diuretics & renal dialysis in
severe cases
54. 4- Treatment of DI
- Hormonal replacement (Desmopressin)
- In nephrogenic DI desmopressin is not
completely beneficial but
- Limitation of salt and water intake and
- Thiazide diuretics are the treatment of
choice
56. Potassium
• Serum potassium (k) range is
3.5 to 5mMol/L
• But 98 % of total body k is intracellular
• Then decrement of 1 mMol of serum
potassium concentration means a loss of
about 200 : 300 mMol/L in body potassium
store.
57. Functions of Potassium
• The main function is the stability of the
action potential of the cell membrane.
• Then the main effect of serum
hypokalemia is hyperpolarization of resting
membrane potential affecting mainly:
• The heart producing arrhythmias and
• The brain affecting the nerve conduction
58. -Potassium also play a role as a cofactor in
enzymatic reactions
-It maintain the normal cell volume
-It affects the IC hydrogen ion concentrations
and participate in regulation of intracellular
PH
60. Hypokalemia
• Hypokalemia means serum level less than
3.5 mMol/L
• Because potassium is primarily an
intracellular ion, hypokalemia may occur in
low, normal, or high total body potassium.
61. Causes of Hypokalemia
• 1- Redistribution e.g.
–Shift of potassium from ECF to ICF
– Insulin
– Metabolic alkalosis
– Catecholamines e.g. aldosteron
– Periodic paralysis
– Anabolism
– Vitamin B12
62. • 2- Non-renal loss of potassium e.g.
– Gastrointestinal loss mainly diarrhea
and repeated suction
– Discontinued diuretics with alkalosis
– Skin loss
63. 3- Renal loss of potassium
The most common causes e.g.
* Diuretics:
It leads to increase renal tubular flow,
aldosteron secretion & alkalosis
*Aldosteron:
Causing potassium waisting in pressence of
sodium ions
64. * Renal tubular damage:
From nephrotoxin drugs
*Diabetic ketoacidosis:
As a result of osmotic diuresis, and
increased excretion of non-reabsorbable
ketoacid anions.
65. Clinical Effect of Hypokalemia
1- Cardiovascular:
arrhythmias then conduction defects
2- Vascular: postural hypotension
3- Muscular: weakness up to cramps
4- Neurological:
hyporeflexia up to impaired mentation
67. Management of Hypokalemia
• General measures:
-Treatment of underlying disease
- Correction of other electrolyte
disturbance
-Discontinue offending drug
-Correction of acid base imbalance.
Monitoring for arrhythmias.
68. Potassium Replacement
• Precautions:
• The maximal infusion in 10 : 40 mMol/h
• The minimal concentration given in
peripheral big vessel is 60 mMol/liter fluid
• Potassium should be diluted in nonglucose
solutions
• Avoid over infusion & hyperkalemia
69. Potassium Replacement
• In severe cases i.e. s.k < 2 mMol/L, or
ECG changes or muscle weakness:
• Give up to 40mMol/h in one litter
normal saline iv.
• In mild to moderate cases i.e. s.k >2
mMol/L and no ECG changes:
• Give up to 10mMol/h iv.
71. Hyperkalemia
• Hyperkalemia means serum potassium
more than 5 mMol/L
• It may occur with low, normal or elevated
total body potassium stores
• Pseudohyperkalemia results if potassium
is released from cells in the test tube.
72. Most Common Causes of Hyperkalemia
• I- Decreased excretory capacity
• II-Excess intake of potassium
• III- Translocation from ICF to ECF
77. Clinical features of Hyperkalemia
• *Neuromuscular manifestations
1- Paresthesia
2- Muscle weakness
3- Flaccid paralysis
4- Mental confusion
78. Treatment of Hyperkalemia
• General Measures:
– Treatment of underlying disease
– Restriction of exogenous potassium
– Removal of offending drugs
79. Treatment of Hyperkalemia
• Mild Hyperkalemia:
• Restriction of potassium and liberalization
of sodium and water are enough.
80. Treatment of Hyperkalemia
• Severe Hyperkalemia:
1-Calcium 5 mMol IV over 5 min.
2-Sodium Bicarb. 50: 100 mMol over 5min.
3-Loop diuretics
4-Glucose and insulin
5-Hypertonic saline
81. Treatment of Hyperkalemia
6- In resistant cases:
Potassium-binding resins in 50ml
sorbitol 20: 30 g orally/4h
7- Inhaled or infused B2 blocker
8- Dialysis