Essential slide for fluid can nd electrolytes

1. FLUID AND
ELECTROLYTE
MANAGEMENT
Dr Thomas Agyen

2. Introduction
A good knowledge of fluid management is
essential for the surgical patient
Delivery of oxygen and nutrients in adequate
amounts pre, intra and post op.
Trauma, severe illness, operative procedures
produce alteration in body fluid composition.
Adequate pre operative stabilization essential to
prevent
– Hypotension, cardiac arrythmias, renal failure and other
intra operative complications

3. FLUIDS PROVIDE:
Solvent for reactions
pH
Exchange of nutrients
Excretion
Excitability: nerve impulses
Temperature regulation
Chemical signals

4. Body water composition
Body is mainly water. 60 + 15 % body weight
– Adult male 60%
– Adult female 55%
– New born infants 75%
TBW increases with lean muscle mass and
decreases with increased proportion of fat.
Percentage TBW decreases with age
– 0-6 months 75% body weight
– 6months – 14 years 65% body weight
– 14years –55years% 50-60% body weight
– >55 years 45-50% body weight

5. BODY WATER
COMPARTMENTS
Total Body Water (TBW) 60% of 60Kg
man
Women 55%
ECF 20% ICF 40%
IVF 4% IF 15%
TF 1%

6. Note:
The Third space is important in disease
Compartments are in Equilibrium
The transcellular compartment is not part
of the equilibrium. It only receives, it
doesn’t give. It is refer to as the third
space.
The equilibrium is between the
intracellular, intravascular and interstitial.
Eg—acute and chronic dehydration.

7. TYPES OF FLUIDS
Crystalloids
• 5% or 10% Dextrose
• Normal saline
• Dextrose saline
• Ringers Lactate
• Badoe’s Solution
• Gastro-intestinal Replacement Solution
(GIRS)
• Fluid 5:4:1 (for Cholera)
• Darrow’s solution

8. Colloids
Blood
Plasma
Hemacel
Dextran 70, 110
Hetastarch
Gelofusin

9. Note:
Crystalloids are small molecules
Colloids are large molecules- collagen
?? Volume to crystalloids : colloids approx.
3:1
Fluid loss eg diarrhoea, vomitus,
burns.give crystalloids
Blood loss  colloids. Ultimate—blood.

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Electrolyte composition Hays 1979
Electrolyte Serum Serum water Interstitial fluid Intracellular fluid
mEq/litre mEq/kg H2O
Cations
Sodium 142 152.7 145 10+
Potassium 4 4.3 4 156
Calcium 5 5.4
Magnesium 2 2.2 26
Total cations 153 165 149 195
Anions
Chloride 102 109.7 114 2+
Bicarbonate 26 28 31 8+
Phosphate 2 2.2 95
Sulphate 1 1.1 20
Organic acids 6 6.5
Protein 16 17.2 55
Total anions 153 165 145 180+

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Basal fluid and electrolyte losses
Based on a 70 kg man
Tropics (Badoe)
Water
Lung and skin 1700ml
Urine 1500ml
⃰⃰ Faeces 200ml
Total 3400
Sodium
Urine 114mmol
Sweat 10-16mmol
Faeces 10
Total 130-140mmol
Potassium
Urine 50mmol
Sweat negligible
Faeces 10mmol
Total 60mmol
Temperate
Lung and skin 1000ml 1000
Urine 1500ml 1500
Faeces 100ml 200
Total 2600ml 2700
Sodium
Urine 75-100 80-110
Sweat
Faeces 10 10
Total 85-110 90-120
Potassium
Urine 60 60
Sweat
Faeces 10 10
Total 70 70

12. Normal water balance
Precise water requirements depend on
– Size of patient
– Age of patient
– Temperature of patient
– Temperature of the environment
Surface area more precise in the
calculation based on size but weight is
easily measurable.

13. FLUID AND ELECTROLYTE
MAINTENANCE IN A HEALTHY
PERSON.
The 70kg man should drink at least 3L of
water in a day.
Food should contain salt and fruits
contain potassium eg coconut, banana
etc.
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14. 12/26/2023 14
Electrolyte solution
Normal
saline
Dextrose
saline
Ringers
lactate
1/5 N
saline in
4.3%dext
.
i/2 n
N
saline/2.5
%dext
Badoe’s
solution
Sodium 154 154 130 30.8 77 43.3
Potassium 0 0 4 0 0 16
Chloride 154 154 111 30.8 77 51.7
Bicarbonate 0 0 27 0 0 9
calcium 0 0 4 0 0 0.65
Glucose 0 50 0 43 25 Sorbitol-
100g

15. Fluid and electrolyte requirements
of a patient.
Basal requirements
Continuing losses above basal
requirements
Preexisting dehydration and
electrolyte loss

16. CAUSES OF FLUID AND
ELECTROLYTE LOSS.
Dehydration
Shock; hypovolumic, cardiogenic,
redistributive, septic.
Intestinal Failure eg obstruction, fistulae
Diarrhoea
Burns.
Vomiting.

17. Continuing loss
During surgery and anaesthesia
Gastric aspirate from NG tube
Sweating, high temperatures.
From drainage tubes and drains
Blood or plasma
– Bleeding, and blood loss from wound
dressing. etc
Excessive diuresis ; thru urethral
cateterization.

18. Basal requirements/maintenance fluid
WATER
Adult 30-40 ml/kg/hr.
– Tropics 3 litres/24hrs.
– Temperate 2.5 litres/24hrs.
Children
– First 10kg 100ml/kg/24hrs or 4ml/kg/hr
– Second 10kg 50ml/kg/24hrs or 40ml/h + 2ml/kg/hr /kg>10kg
– Additional kg 25ml/kg/24hrs or 60ml/hr +
1ml/kg/hr/kg>20kg
Eg a child weighing 25kg will require a maintenance fluid of
10(100) + 10(50) + 5(25)=1625mls in 24hrs

19. Basal requirements/maintenance fluid
Fever 500ml/ 24hrs/oC above 38o. Sweating 500ml/24hr/5o rise
in environmental temperature
ELECTROLYTES
Sodium
– Tropics 130mmol.
– Temperate 80-100. or 1mmol/kg
Potassium
– Tropics 50mmol or 3g/24hrs
– Temperate 60mmol or 3g/24hrs
Urine output at least 30-40ml/hr
Not more than 40mmol added/litre
No faster than 40mmol/hr

20. Which fluids for basal needs
Tropics
– 1 litre Ringers lactate + 2 litres of 5% dextrose +3g KCl/24hrs
– 1 litre normal saline + 2 litres of 5% dextrose + 3g KCl /24hrs
– Badoes solution 3l / 24hrs
Temperates
– 500ML Normal saline + 2 litres 5% dextrose+ 3g KCl / 24hrs
– 2.5 litres of 1/5 normal saline + 3g KCl / 24hrs
Children
– 1/5 Normal saline + potassium requirement (5mmol/ 250mls n/s)
Other additions include vitamins

21. Assessment of deficit
History, physical examination laboratory investigations
Dehydration
Thirst, dry mucus membranes, sunken eyes & fontanelles, cheeks,
loss of skin turgor and weight loss.
Weakness, extreme cases mental confusion.
Cardiovascular system
– Tachycardia, peripheral vasoconstriction, decrease pulse pressure,
fall in BP
– Central venous pressure (CVP)
– Pulmonary capillary wedge pressure (PCWP)
Gut intramucosal pH (pHi). 1st to suffer during haemorrhagic loss
Urine output
Measure FBC, BUE & Serum creatinine

22. DEHYDRATION
Adults(BW)
Mild 2%
Moderate 4%
Severe 6%
Children(BW)
5%
10%
15%

23. Correction of pre-existing dehydration or fluid loss
Usually done intravenously
Problems
– To identify which compartment(s) fluid has been lost
– To assess the extent of dehydration
Fluid used must be similar in composition and
volume to fluid lost
History of fluid loss of paramount importance
– Bowel losses come from ECF
– Protein losses from plasma, blood ,transudates
– Combination of all the above.

24. Water, electrolyte and plasma replacement
Replace ECF losses with Ringers lactate, normal
saline or dextrose saline
Gastric outlet obstruction
– Normal saline or dextrose saline with added
potassium
NB-RL is contraindicated because it worsens
alkalosis
Obstructed bowel
– Ringers lactate, normal saline dextrose saline with
added potassium, or GIRF
Blood or plasma
– Dextrans, haemacel (gelatin), gelofusine, hetastarch
– Albumin

25. colloids
Preserve a high intravascular osmotic
pressure
Eg Hydroxyethyl starch(HES), Gelofusine,
Dextran, blood
HES is frequently used to prevent shock ff
severe blood loss caused by trauma or
surgery by ingreasing blood volume
Gelofusine contains albumin which also
acts by increasing intravascular volume
hence increasing CO,BF,O2 transport.
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Colloids
Although no significant differences in outcome
have been demonstrated by the use of colloids
vs crystalloids,
larger amounts of crystalloids are required to
achieve the same intravascular volume
Crystalloids are much cheaper than colloids and
also easily accessible

27. COMPLICATIONS
• Overload
• Embolism; virchow triad.
• DVT
• Immune Reactions
• Infections
• Bleeding- dextran

28. MONITORING
Non-Invasive
BP, Pulse, Respiratory rate
Veins
Sensorium
ECG
Oxygen saturation
Urine Output
Temperature

29. Invasive
Intra-arterial BP
CVP
Sivan Ganz Catheter

30. ELECTROLYTE IMBALANCES
HYPONATRAEMIA
Serum Na+ 130mmol/L
Causes
Diarrhoea
Vominting
Peritonitis
Fistulae

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Electrolyte derangement (Sodium)
Hyponatraemia (Na.<130mmol/l)
– Iatrogenic, water intoxication(orally/excess 5%d,
GOO, renal insufficiency, cirrhosis,
hyperglycaemia (osmotic diuresis), Diuretics
Clinical features
– Confusion, seizures, hypertension, muscle
weakness
Treatment
– If 20 to excess free water– fluid restrict
– Calculate Na deficit = (140 – Na measured) x TBW
( 60% wt in kg)
– If deficit is severe enough to cause CNS effect
replace ½ Na with 3% hypertonic saline over 4-
6hrs
– Correct underlying cause

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Electrolyte derangement (Sodium)
Hypernatraemia (Na >150mmol/l
– Loss of free water in excess of sodium (sweating,
fever, renal failure, diabetes insipidus(↓ADH), burns,
osmotic diuresis(DM) ,excess saline infusion
Clinical features
– Thirst, confusion, coma, fits with signs of
dehydration
Treatment
– Give water orally if possible; if not, 5% dextrose IV
slowly(4L/24Hr) guided by urine output.
– 0.9% saline esp if hypovolaemic as this causes less
marked fluid shift and is hypotonic in hypernatremia
– Avoid hypotonic solutions

33. HYPOKALAEMIA
• Very common
• Serum K+ 3.5mmol/L
• Total body K+ with ¾ in muscle
• Only 2% is found in ECF so hypokalaemia
is quickly established
• Causes include
– Vomiting, Diarrhoea
– Peritonitis
– Diabetic ketosis
– Drug- diuretics

34. Symptoms
• Slowed speech
• Drowsiness
• Weakness
• Palpitations
• Arrhythmias
• Constipation
• Abdominal
distension
Signs
• Irregular pulse
• Hyporeflexia
• Bowel Sounds
• Abdominal
distension

35. Investigation:
– BUE
– ECG
Treatment
– Rehydrate
– Correct deficit
– Urine output increases
– IV KCL 20mmol/hr (90-150mmol max)
– Regular daily BUE and ECG

36. HYPERKALAEMIA
Common
Causes
– Renal Failure
– Transfusion of old blood or massive blood
transfusion
– Chemotherapy
– Muscle destruction as in trauma
Symptoms: As for hypokalaemia

37. Signs
– Irregular Pulse
– Arrhythmias
– Hypotonia
– Others as in hypokalaemia
Investigation
– BUE
– ECG

38. Treatment
Rehydrate if pre-renal
Urine output: challenge kidneys
Give calcium gluconate
Insulin + glucose
Exchange resins
Peritoneal / haemodialysis

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Calcium
Hypocalcaemia
– Hypoparathyroidism, decreased serum
albumin, pancreatitis renal dx etc
Clinical features
– Chvostek, Trousseau, carpopedal spasms
Treatment
– IV calcium gluconate or chloride

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Calcium
Hypercalcaemia
– Malignancy, hyperparathyroidism, hypervitaminosis
D, milk alkali syndrome, paget’s dx, sarcoidosis etc
Clinical
– Nocturia, polydipsia, nausea, anorexia, vomiting,
abdominl pain
Treatment
– Hydration
– Induce diuresis
– Corticosteroids
– Mithramycin
– Calcitonin
– biphosphonates