Fuids and Electrolytes balance in human body.

1. DR MUHAMMAD ASIF KHAN
FLUID AND ELECTROLYTE
BALANCE
DR MUHAMMAD ASIF
KHAN

2. FLUID COMPARTMENTS
•WATER
• comprises 60% of body weight
• Percentage is lower in obese
• 2/3 and 1/3 rule
2/3 of water is present in intracellular space
=66%
1/3 of water is present in ECS=33%
2/3 of ECF=interstitial space=22%
1/3 of ECF=intravascular space=11%

3. ELECTROLYTES
• INTRACELLULAR ELECTROLYTE
cation=K
anion =protein and glycogen
• EXTRACELLULAR ELECTROLYTE
cation =Na
anion=Cl and HCO3

4. PARENTRAL FLUID THERAPY
• 2 Types
1.Crystalloids
2.colloids

5. 1.CRYSTALLOIDS
• Aqueous solution of mineral salts or water soluble molecules
• K, Ca and lactate are added to make their ionic composition comparable
with that of plasma
• TYPES
• 1.NORMAL SALINE
• 0.9% saline
• 154 mmol of NA and chloride each
• osmolarity is close to plasma (308)
2.HALF SALINE
• 0.45% saline
• it contain 77mmol of Na and chloride each
• has osmolarity of 154

6. 3. 5% DEXTROSE
• composed of 50g of glucose in 1L of water
• contains 200 Kcal
• has osmolarity of 250
4. 10% DEXTROSE
Contains 100g glucose in 1L of water
5. DEXTROE SALINE
It is 5% dextrose with normal saline
Osmolarity is 564

7. • 6.DEXTROSE HALF SALINE
• It is 5% dextrose with half saline
• has osmolarity of 350
7.PAEDS SOLUTION
• 0.18% saline with 4% dextrose
• Contain 30mmol of Na and cl each
• With 40g of glucose in 1L
• Has osmolarity of 284

8. • 8.RINGER LACTATE
It has
Na=130mmol
Cl=109mmol
lactate=28mmol
K=4
Ca=3
Osmolarity=273

9. • 9. HARTMANS SOLUTION
It has
Na=131
Cl=111
HCO3=29
k=5
Ca=2
10. 3% SALINE
• Hypertonic saline
• Contain 512 mmol of Na and Cl
• Used for cerebral edema and hyponatremic seizure

10. 2.COLLOIDS
• These fluids contains high molecular weight substances e.g. protein
and branched polysaccharides which cant cross plasma membranes
and exert osmotic pressure within the vessel to retain fluids within
the vessel (for 6 to 24 hours) unless removed by reticuloendothelial
system
• Care should be taken because of risk of CCF, coagulopathy,
pulmonary edema and life threatening anaphylactic reactions

11. • The available colloids are
1.Blood
2.Albumin
3.Haemacel
4.FFPs
5.Hetastarch
6.Gelatine

12. NOTE :WHICH FLUID IS PREFERRED IN
EMERGENCY SETTING?
• If there is severe hypovolemia and capillary integrity is intact
then prefer colloids because they remain within vessel and
retain fluid within vessel to maintain intravascular fluid and
tissue perfusion
• If capillary integrity is disturbed as in case of burn then prefer
crystalloids as colloids escape in interstitial space and lead to
severe edema

13. PRINCIPLES OF FLUID THERAPY
• To maintain effective circulatory volume while minimizing interstitial
edema
• To incorporate deficit, maintenance fluid and ongoing loss
• Prefer oral route when possible
• Iv fluids should be discontinued as early as possible
• Appropriate fluid should be used (fluid whose composition is similar
to that of lost fluid)
• Check electrolyte before the start of fluid therapy

14. COMPONENTS OF FLUID THERAPY
Fluid therapy has 3 components
1.Resuscitation
2.Maintenance therapy
3.Replacement therapy

15. • 1.RESUSCITATION
Fluid given to replenish the deficit as in case of
• Blood loss from surgery and trauma
• Plasma loss from burn
• GI losses from diarrhea vomiting etc.
.

16. • Give initial bolus of 500ml (4ml/kg)
• Give further fluid according to response to initial fluid bolus
• Continue resuscitation until effective circulatory volume and tissue
perfusion is achieved with normalized vitals
• Transfuse blood if there is more than 30% of blood loss
• Check and correct electrolyte accordingly

17. 2.MAINTENANCE THERAY
-It is the amount of fluid required on daily basis under normal
circumstances
-Normal requirements are
• Water is 35 to 40ml/kg/day
• Na is 1-2mmol/kg/day (70 to 150mmol/day)
• K is 0.6-1mmol/kg/day (40 to 60 mmol/day)
• Ca is 5mmol/day
• Mg is1mmol/day

18. • NOTE-
Children require more water than adults
Requirement of fluid is as follow
At birth-
75ml/kg/day
DURING 1ST WEEK OF LIFE-
150ml/kg/day
AFTER 1ST MONTH OF LIFE- Fluid requirement is according to 4/2/1
formula
e.g. 4ml/kg/hour for 1st 10kg of body weight
2ml/kg/hour for next 10 kg of body weight
1ml/kg/hour for next kg of body weight

19. FACTORS AFFECTING THE MAINTENANCE
REQUIREMENT
1. FACTORS IN WHICH INCREASED WATER INTAKE IS REQUIRED
• sweating
• burn
• tachypnea
• fever (fluid requirement increase by 200ml/day per 1C rise in body

20. 2.FACTORS IN WHICH DECREASED WATER INTAKE IS REQUIRED
• Oliguric RF
• Hypothyroidism
• Use of humidified air

21. 3.REPLACEMENT THERAPY
• It is equal to maintenance fluid plus fluid to replenish ongoing loss
(NG aspiration, drain, GI fistula, diarrhea, vomiting)
.THE PRINCIPLE is like for like fluid replacement
Means prescribe the fluid whose ionic composition is similar to the
fluid lost

22. HOW FAST?
• 1.IN SEVERE HYPOVOLEMIA
-1-2L of N/S is given rapidly to restore tissue perfusion
-Fluid repletion is rapidly continued until vitals are normalized
2.IN MILD TO MODERATE HYPOVOLEMIA
administer 50-100ml of fliud per hour in excess of fliud lost

23. HOW TO CALCULATE IV FLUID RATES
• Fluid is administered at a specific rate
• Measured as drops/mint, ml/mint, l/hour
• Burette has a needle or plastic dropper that determine number of
drops per ml
• Available drop factors are
1.blood set= 10 drops/ml
2.regular set= 16drops/ml
3.micro drop=60 drops/ml

24. CALCULATION OF DROPS PER MINUTE
Drops per minute
DPM=total fluid in ml ÷ time in mints x drop factor =drop/mint

25. WATER BALANCE
• 1.Water depletion
It is depletion of pure water while maintaining electrolytes
it leads to hypovolemic hypernatremia and increased osmolarity
Causes:
1.Decreased intake as in case of unvailbility of water ,inability to
swallow
2.Fluid loss from lungs after tracheostomy
3.Excessive sweating

26. • C/F:
• Intense thirst
• Weakness
• Dry tongue
• Decreased UOP
MANAGEMENT:
• Oral rehydration
• Iv fluids in case of severe dehydration

27. • 2.WATER INTOXICATION:
Excess of water that leads to dilutional hyponatremia
It occurs when excess amount of water or hypotonic solution is given
by any route
CAUSES:
• Excess 5% dextrose
• TUR syndrome
• SIADH

28. • C/F:
Nausea/vomiting
Weakness/drowsiness
Convulsion /seizure
MANAGEMENT:
Stop water intake (best therapy)
Add diuretics
Inf of hypertonic saline with intense monitoring to avoid neuronal
dehydration

29. SODIUM BALANCE××
• Sodium is principle cation of ECS
• Serum Na=135-145mmol/l
• Intracellular Na=8mmol/L
• it is responsible for 90% of oncotic pressure
• CALCULATION OF Na DEFICIT
140 - Measured Na × o.2 × Weight in kg

30. • 1.HYPONATREMIA
-It is defined as serum Na less than 135mmol/L
-Usually asymptomatic
It may manifest as
• Anorexia
• Lethargy
• Confusion
• Seizure
• Comma

31. • Untreated acute hyponatremia may cause cerebral edema
Types :
3 types
1.Hypovolemic hyponatremia
2.Euvolemic hyponatremia
3.Hypervolemic hyponatremia

32. • 1.hypovolemic hyponatremia
It is sodium deficit with relatively smaller deficit
Causes
Diuretic therapy
Diarrhea
Vomiting
Burns
Management
Isotonic saline

33. • 2.EUVOLEMIC HYPONATREMIA
-It is sodium deficit with water retention alone
- Causes
• Excessive infusion of sodium free water
• SIADH
• Hypothyroidism
Management
Water restriction to 0.5L to 1 L

34. • 3.HYPERVOLEMIC HYPONATREMIA
- It is sodium retention with relatively greater water retention
- It may be acute or chronic
• Acute TUR syndrome is a medical emergency that may result in cerebral
edema or pulmonary edema
It is treated with loop diuretic or hypertonic saline
• Chronic
Causes of chronic hypervolemic hyponatremia are
CCF
Cirrhosis
Nephrotic syndrome
CKD

35. • 2.HYPERNATREMIA
it is defined as serum sodium more than 145mmol/l
Causes
• Decrease water intake
• Diarrhea
• Vomiting
• Burns

36. • Insensible losses
• DI
C/F
• nausea
• confusion
• convulsion

37. • Management
In case of acute:
• It need rapid correction to avoid neuronal shrinkage
• Correct with 5% dextrose or half saline(at initial rate of 50-
70ml/hour)
• Treat underlying cause

38. POTASSIUM BALANCE
• It is main intracellular cation
• Serum level=3.5-5.5mmol/L
• Intracellular level is 140-150mml/L
• It is necessary for neuromuscular control and regulates
skeletal, cardiac and smooth muscle function

39. • 1.HYPOKALEMIA
- It is defined as serum potassium less than 3.5mmol/L
- Causes
• Decreased intake in diet, use of potassium free iv fluid or K deficient TPN
• Excessive potassium excretion
• In hyperaldosteronism
• Diuretics, steroids and aminoglycosides use
• GI losses e.g. diarrhea
• Renal losses of potassium to conserve sodium in response of GI losses

40. • C/F
• Weakness
• Paralytic ileus
• Hypokalemic nephropathy i.e decrease potassium causes damage to
renal tubule and interfere with tubular response to ADH causing acquired
nephrogenic diabetes insipidus with polyuria and polydipsia
• Cardiac arrhythmias
Management
1. Oral potassium in form of milk, honey, banana, fruit juices
2. Tb KCL 2g available
3. I.V potassium is given according to potassium deficit which is calculated
as
K DEFICIT=(4 - Measured K) × 0.6 × Wt. in kg

41. Note – safe rule for IV potassium
• Never inject as bolus
• Add to crystalloids
• UOP should be at least 40ml/hr before giving iv potassium
• Do not add more than 40mmol K to one liter of solution
• if 1Liter solution contain 40mmol potassium it should not be
infused in less than 4 hours

42. 2. HYPERKLEMIA
-It is defined as serum potassium more than 5.5mmol/l
-Causes
1. Excessive K intake from oral or iv supplements
2. Increased release of potassium from cell, as in case of
• Hemolysis,
• Rhabdomyolysis,
• Crush injuries
• Acidosis and increased osmolarity from hyperglycemia or iv mannitol
3. Impaired K excretion
4. Renal insufficiency
5. medications like k sparing diuretics, Nsaids

43. • C/F:
1.Weakness
2.Renal failure
3. Nausea, vomiting, diarrhea, intestinal colic
4. Arrhythmias, cardiac arrest

44. Management
• 10ml of 10%calcium gluconate
• 10 units of insulin-R in 50ml of 25%dextrose OR
• Salbutamol 2.5mg in 100ml of 5% dextrose is given to push
potassium back into cells
• NaHCO3 to correct acidosis
• Ion exchange resins to neutralize excess potassium
• Dialysis in severe cases

45. • HYPOCALCEMIA
It is defined as serum calcium less than 8.5mEq/L or ionized calcium less than
4.2mg/dl
Causes:
1. Pancreatitis
2. Massive soft tissue infection
3. Toxic shock syndrome
4. Pancreatic or small bowel fistulas
5. Hypoparathyroidism
6. Renal failure

46. C/F:
• Muscle spasm
• Convulsions
• Hyperreflexia
• Carpopedal spasm
• Laryngeal spasm that leads to stridor
• Chvostec sign
• Trouseau sign

47. Management:
• Calcium Gluconate
• Vitamin D Supplements

48. THANK YOU