Fluid And Electrolyte Management Flashcards
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 complications such as?(state three )
–
Name six things fluids provide
Body composition is made up mainly of what?
How much percentage of the body weight is water?
(Mention for adult male,female and new born infants )
What does Total body weight increase with or decrease with?
Percentage Total body weight decreases with what?
Hypotension, cardiac arrythmias, renal failure and other intra operative complications
.Solvent for reactions
•pH
•Exchange of nutrients
•Excretion
•Excitability: nerve impulses
•Temperature regulation
•Chemical signals
Body water composition
•Body is mainly water. 60 + or minus 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
What is the total body water of the adult male?
The body water is distributed in two how many compartments?
Name them
How much does each compartment comprise of the body weight in percentage and in Litres
Total Body Water (TBW) 60% of 60Kg man
•Women 55%
Thebodywaterisdistributed in2compartments:
l. Intracellular - 40% of body weight.(28L)
2. Extracellular - 20% of body weight.(14L)
(i) Intravascular (plasma) - 4%.(2.8L)
(ii) Extravascular
(a) Transcellular - 1%(0.7L)
(b) Interstitial- 15%.{11L)
What is referred to the third space?
What separates the interstitial fluid from plasma?
What comprises of transcellular fluid?
What’s the function of the ECF?
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.
The interstitial fluid is separated from the plasma only by a capillary membrane which permits rapidtransferofallexceptlargeprotein molecules and cellular elements. The interstitial fluid and plasma therefore act as one compartment. Transcellular fluid comprises gas- trointestinal secretions, cerebrospinal fluid and fluid injoints and the eye.
The Extr acellular Fluid (ECF): The extracellular fluid - the “inland sea” - bathes the cell mass and carries to it nutrients and oxygen from the gastrointestinal tract and lungs respec- tively, and removes waste products and carbon dioxide for excretion by the kidneys, liver and lungs. It does to the cell mass what the sea does to the fishes.
State the two major types of fluids and give three examples under each
When do you give Each types of fluid?
What is the ratio of the volume of one type of fluid to the other?
Crystalloids
•5% or 10% Dextrose
•Normal saline
•Dextrose saline
•Ringers Lactate
•Badoe’s Solution-Badoe’s Maintenance Solu~ion(Na+43.3, K+ 16, Ca2+ 1.3, Cl 5I.7, HC0; 9mmol, Sorbitol 1OOg/L).
•Gastro-intestinal Replacement Solution (GIRS)
•Fluid 5:4:1(5gNaCl; 4gNaHC03 1g KCI) (for Cholera)
•Darrow’s solution(potassium lactate)
Colloids
•Blood
•Plasma
•Hemacel
•Dextran 70, 110
•Hetastarch
•Gelofusin
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.
Precise water requirements depend on what factors?
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.
How does the body lose and gain water
Based on a 70kg man,how much water ,sodium and potassium is lost from sweat,faeces,urine in the tropics and in the temperate region
The body loses water through expired air, skin, urine and faecesand gains it from food, liquids and endogenous metabo- lismofcarbohydrate, protein and fat.
Sodium and potassium are lost in sweat, urine and faeces andarereplaced from food
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
How much water should a 70kg man drink in a day
However, the surgical patient who usual Iy requires parenteral ftuidtherapy is not likely to be passing faeces, and so requires in24h, 3 litres in a tropical region and 2,300 in a temperate region.For1°Crise, 12%ofthedailyrequirement isadded 10compensate for water lost in sweating.
True or false
Since, as mentioned above, the surgical patient who requires parenteral therapy is not likely to pass faeces, daily electrolyte requirements are 130 mmol of sodium and 50 mrnol of potassium in the tropics and 80-110 mmol of sodium and 60 mmol of potassium in a temperate region
True or false
What are the fluid and electrolyte requirements are f a patient
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.
Fluid and electrolyte requirements of a patient.
•Basal requirements
•Continuing losses above basal requirements
•Preexisting dehydration and electrolyte loss
How much energy should a surgical patient be given daily
And how is their fluid requirement met ?
The surgical patient should therefore be given at least 2L of 5%glucose daily for energy. Sorbitol, which can be infused inconcentrationsofup to30% peripher-
ally, will provide more energy. Glucose5g/kg/day is advisable to provide more exogenous energy iflV therapy is prolonged.
They need
Water. 3 litres
Sodium 130 mmol (2mmol/L)
Potassium 50 mmol(1-2mmol/L)
Carbohydrate 100g(2g/kg/day)
requirements
So it is given in the form of the fluids below
(i) 1 litreof R.inger’s lactate
(Na” 130,K+4,Ca2+4,Cl-. 111 and HCO; 27 mmol/L).
(ii)2 litres of 5% dextrose.
(iii)SOmmol of potassium chloride.
Vit. B complex and C are added.
What are the compositions of electrolytes and state the value for each electrolyte in the serum,serum water(mEq/Litre),interstitial fluid,Intracellular fluid(mEq/kg H2O)
Cations
•Sodium
142:serum
152.7:serum water
145:Interstitial
10+ intracellular fluid
•Potassium
4:serum
4.3:serum water
4:Interstitial fluid
156:Intracellular fluid
•Calcium
5:serum
5.4:serum water
•Magnesium
2:serum
2.2:serum water
26: Intracellular fluid
Total cations
153:serum
165:serum water
149: interstitial fluid
195:Intracellular fluid
Anions
Chloride
102:serum
109.7:serum water
114: interstitial fluid
2+ or - : Intracellular fluid
•Bicarbonate
26:serum
28:serum water
31: Interstitial fluid
8+ or - : Intracellular fluid
•Phosphate
2:serum
2.2:serum water
95: Intracellular fluid
•Sulphate
1:serum
1.1:serum water
20:Intracellular fluid
Organic acids
6:serum
6.5:serum water
•Protein
16:serum
17.2:serum water
55:Intracellular fluid
Total anions
153:serum
165:serum water
145:Interstitial fluid
180+ : Intracellular fluid
What are the components of electrolyte in these solutions (Normal saline,dextrose saline,Ringers lactate,1/5NSaline in 4.3% dextrose,1/2Nsaline in 2.5% dextrose,Badoe’s solution
Normal Saline has 154 Sodium,no potassium,154 Chloride,no bicarbonate or calcium or glucose
Dextrose saline has 154 Sodium,no potassium,154 Chloride,no bicarbonate or calcium and has 50 glucose
Ringers has 130 sodium,4 potassium,111 chloride,27 bicarbonate,4 calcium, no glucose
1/5NSaline in 4.3% dextrose has 30.8 sodium,no potassium,30.8 chloride,43 glucose,no bicarbonate or calcium
1/2Nsaline in 2.5% dextrose, has 77 sodium,no potassium,77 chloride,25 glucose, no bicarbonate no calcium
Badoes solution
Sodium 43.3,potassium 16,Chloride 51.7,bicarbonate 9,calcium 0.65,sorbitol (glucose)100g
State seven causes of fluid and electrolyte loss
CAUSES OF FLUID AND ELECTROLYTE LOSS.
•Dehydration
•Shock
•Intestinal Failure eg obstruction, fistulae
•Diarrhoea
•Burns.
•Vomiting.
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.
What is the maintenance fluid or basal requirements for adults and children
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
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
Which fluids are needed for basal needs
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
How are deficits in fluids assessed?
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
•Quantification of plasma and ECF loss
% fall in ECF volume = (1- Pr1/Pr2) x 100
% fall in plasma volume
= (1- [Hct1/100-Hct1 x 100-Hct2/Hct2] )
Na deficit= (140 – measured Na) x TBW [TBW = 0.6 x wt in kg]
What percentage of body weight in adults and kids is referred to as mild,moderate,severe dehydration
DEHYDRATION
Adults(BW) •Mild 2%
•Moderate 4%
•Severe 6%
Children(BW)
Mild 5%
Moderate 10%
Severe 15%
