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Fluid/s
Prof. Mridul M. Panditrao
Professor, Head & In-Charge of ICU
Dean of Academic Affairs
Department of Anaesthesiology & Intensive Care
Adesh Institute of Medical Sciences & Research
(AIMSR)
Adesh University
Bathinda, Punjab, India
Introduction
Water is life!
Journey of life starts in Water!
Water is also a dramatic Paradox
Too less or too much = Incompatible with life
So the life is geared up around maintaining the
equilibrium !!
In Fact entire life of the living thing is spent in maintaining
The fluid balance
pH balance
Introduction
Quantitatively most important Body constituent
Males = 60%
Of the total body weight
Females 50%
The lesser percentage in females because of larger fat
content.
Water is found in each and every tissue of the body,
including bones and cartilages!
Body
Compartments Total Body Mass
Total Body Water (TBW)
Extra Cellular Fluid (ECF) Intra Cellular Fluid (ICF)
Solid Tissues
Intra Vascular Fluid Interstitial fluid
Distribution of Body water
Intra-Vascular Compartment
5%
Interstitial Compartment
15%
Intra- Cellular Compartment
40%
Tissues
40%
Percentage Distribution of Various Body Compartments
Intra-Vascular Compartment Interstitial Compartment Intra- Cellular Compartment Tissues
Definitions
Total Body Water (TBW) :
The sum of intracellular water and extracellular water (volume)
The latter consisting of
the interstitial or tissue fluid
the intravascular fluid or plasma.
About 60% of body weight
http://medical-dictionary.thefreedictionary.com/total+body+water
http://www.medilexicon.com/medicaldictionary.php?t=99650
Definitions
The Extra-Cellular Fluid (ECF): The water content found outside the body cells
Constitutes two major compartments
Inra-vascular & interstitial
Also contain the trans-cellular fluids that are formed by active transport processes
Include the fluids of the eye and the secretory glands e.g. saliva, GIT and sweat glands
In the cavities and channels of the brain and spinal cord (Cerebrospinal fluid, CSF)
Lymph
In body cavities lined with serous (moisture-exuding) membrane and
In muscular and other body tissues
Ingested water or water produced by the body's metabolic processes (metabolic water).
http://www.britannica.com/EBchecked/topic/199041/extracellular-fluid
Definitions
Intra Cellular Fluid ( ICF):
a fluid within cell membranes of the tissue cells, throughout
most of the body
containing dissolved solutes that are essential to
electrolytic balance and to healthy metabolism.
Also called intracellular water
constituting about 30–40% of the body weight.
http://medical-dictionary.thefreedictionary.com/
www.medilexicon.com/medicaldictionary.php?t=34113
Rule of 1/3
Out of all the compartments in TBW
We can manipulate only ECF Compartment
More specifically only Intra-Vascular Compartment
Quantity of ECF is 1/3rd of the TBW
Quantity of Intravascular Compartment is 1/3rd of ECF
Intra Vascular Volume: Blood
Blood Volume: is the volume of blood (both red blood
cells and plasma) in the circulatory system of any
individual.
Effective Circulating Volume: that proportion of
Intra- vascular volume ( thus of ECF) that is effectively
perfusing the tissue cells
It is in direct proportion to the
ECF
Solute Content dissolved in it ( esp. Na+ salts)
Solutes hold the water in ECF
Solutes:
Solute: A substance dissolved in another substance or water
both of in-organic as well as organic origin
Solutes in ECF: by and large of in-organic type
E.g. Na+, Cl-, HCO3
-,
Solutes in ICF: Mixture of Both
E.g. K+, Organic Phosphate esters( ATP, CreatinePhosphate… etc.)
•Mole - A mole is the amount of a substance that contains the number
of molecules equal to Avogadro's number.•The mass in grams of one mole of a substance is the same as the number of atomic mass units in one
molecule of that substance.
•i.e. the molecular weight of the substance expressed as grams)
•The mole (symbol: mol) is the base unit in the SI system for the amount of a substance
•Molality of a solution is the number of moles of solute per kilogram of
solvent
•Molarity of a solution is the number of moles of solute per liter of
solution
Avogadro's number - this is the number of molecules in
one mole of a substance (ie 6.022 x 1023)
Osmole
The amount of a substance
that yields, in ideal solution
that number of particles = (Avogadro’s number)
that would depress the freezing point of the solvent by 1.86K
Osmolality & Osmolarity
Osmolality: Osmolality is a measure of the number of
solute particles present in solution
Is independent of the size or weight of the particles
Expressed as : milliosmoles per kilogram of water ( m
Osmol/Kg)
Osmolality of a solution is the number of osmoles of solute
per kilogram of solvent ( m Osmol/Kg)
Osmolarity of a solution is the number of osmoles of solute
per liter of solution ( m Osmol/L)
http://www.anaesthesiamcq.com/FluidBook/fl2_3.php
Osmolality & Osmolarity
The value measured in the laboratory is usually referred
to as the ‘osmolality’
The value calculated from the solute concentrations is
reported by the laboratory as the ‘osmolarity’
The Osmolar gap is the difference between these two
values
Tonicity
Tonicity is the effective osmolality
Is equal to the sum of the concentrations of the solutes
which have the capacity to exert an osmotic force
across the membrane
Osmolality is a property of a particular solution and is
independent of any membrane
Tonicity is a property of a particular solution in reference
to a particular membrane
Tonicity
It is strictly wrong to say this or that fluid is isotonic with
plasma
what should be said is that the particular fluid is isotonic
with plasma in reference to the cell membrane
By convention, this specification is not needed in
practice as it is understood that the cell membrane is the
reference membrane involved.
Tonicity Vs. Osmolality
refers to the relative
concentration of two solutions.
hyperosmotic, means the
concentration of solutes
outside the cell is greater than
the concentration inside the
cell
• refers to what the cell
does in a certain
environment.
• If the environment is
hypertonic, the cell will
shrink due to water
leaving the cell.
• Hypotonic means water
enters the cell makes it to
expand and possibly
explode.
Effect is same:
If a hyperosmolar/ hypertonic solution was administered to a
patient, this would tend to cause water to move out of the cell.
Electrolytes: definition
An electrolyte
is a substance that ionizes when dissolved in suitable
ionizing solvents such as water
This includes most soluble salts, acids, and bases
Some gases, such as hydrogen chloride, under
conditions of high temperature or low pressure can also
function as electrolytes
Cations: Positively charged e.g. Na+, K+, Ca++, Mg++
Anions: Negatively Charged e.g. Cl-, HCO-, OH-, HPO4--
,SO4--
http://en.wikipedia.org/wiki/Electrolyte
Main Electrolytes per Compartment
Electrolytes (mEq/L) ECF: Cations ECF: Anions ICF: Cations ICF: Anions
Sodium Na+ 135 - 145 - 8 -10
Potassium K+ 3.5 - 5.5 148 -152
Calcium Ca++ 7 - 10 0.001
Magnesium Mg++ 1.5 - 4 40!
Chloride Cl- 95 -105 1-2
Bicarbonate HCO3 - 20 - 24 4-7
Phosphate HPO4 +
Sulphate SO4
145 - 155 5 - 9
Plasma Osmolality
Plasma or Serum Osmolality is Number of solutes
dissolved in plasma
Normal range is : 275 -290 m Osmols/ Kg of Plasma
Equation for calculation:
Plasma Osmolality = 2x S. Na + S. Glucose/18 + BUN/2.8
Conversion factor for BUN = B. Urea(mg/dl) /2.14
P. Osmol = 2x S. Na + S Glucose/18 + B. urea x 2.8/ 2.14
Body Water Regulation
Increase in osmolality stimulates osmo-receptors
in antero-lateral hypothalamic nuclei
Thirst
Neuro-hypophysis
ADH & AVP
Decreased excretion by increasing
re-absorption.
Insensible water loss
Skin = 400 - 450 ml/day
RS = 400 - 500 ml/day
GIT (Stool) = 100-200ml/daay
Sweat is not insensible loss
Total Minimal loss around 1L/day
Calculation
Daily Total imperative requirement in a surgical patient/
person is
= absolutely required minimal Urine output + 800-1000 ml
In a 60 kg male
i.e. 0.6-0.7ml/kg/hr + 800-1000 ml
40ml/hr = 1000ml + 1000 ml
2000ml/24 hrs = 80 – 100ml/hr
Classification of I V Fluids
Blood and Products
I V Fluids
Non blood I V Fluids
Crystalloids Colloids
Glucose Containing
Electrolyte solutions
Mixed
Proteinous Non proteinous
Polygelins
• Haemaccel
• Gelofusin
Albumin
20% & 5%Starches Dextrans
HES
PentaStarch
Tetrastarch
Lomodex (Dextran 40)
Macrodex (Dextran 70)
Rheomacrodex (Dextran
110)
Relative tonicity
Isotonic : R L, 1N NaCl,D5W (inside body becomes
hypotonic)
Hypertonic: 5DNS, 5D in RL, 5D in ½ N NaCl, 3% NaCl
Hypotonic: ½ N NaCl
20% Albumin has osmotic effect 5 times its volume
i.e. 100 ml will increase plasma volume by 400-500ml
Given at the rate of 1-2 ml/min
Correcting fluid deficit is absolutely inperative
5% will increase only by 100 ml ( 0.5-1 ml/min)
Colloids: Dextrans
Dextrans are branched polymers of Glucose molecule
40, 70 and 110 are, mol. Wts : 40000, 70000 and 110000 Daltons
40 is 10% while 70 is 6%
Act as Antithrombotic, by decreasing RBC aggregation
Total dose not more than 20ml/kg in 24 hrs
Hyperglycemic effect
Not commonly used nowadays
Colloids : starches
Excellent Volume expanders
All of the volume remains inside Intra vascular compartment
Effect lasts for 4-6 hours
Interference with platelet aggregation: HES> Penta> tetra,
Least
Increase the volume by nearly 100 to 150 % depending upon
% conc.
Tetrastarch: Voluven Better of all
Made from corn starch: least antigenic
Up to 35ml – 50 ml/ kg/ 24 hours can be given
Colloids: Polygelins
Modified: degraded gelatin polymers
Derived from animal bones
Can expand plasma by 50%
Do not have any interference with agglutination, platelet
aggregation
Have been found have variety of allergic reactions :
minor to anaphylaxis
Have been implicated in transmission of Creutzfeldt-
Jakob’s disease (Mad Cow disease) to humans
Slowly becoming obsolete
Hypovolemia
ECF Volume Reduced
Extra renal
Hemorrhage
Gastro-intestinal
Skin
Renal
Diabetes insipidus
Diabetes mellitus
Drugs: Diuretics
Hypoaldosteronism
Salt wasting nephropathies
Hypovolemia
ECF Volume increased ( Low circulatory/Intra-Vascular volume)
Decreased Cardiac Output
CCF
Redistribution of Fluid
Decreased PCOP
Cirrhosis
Nephrotic Syndrome
Capillary leak
Ischemic Bowel: Third space loss
Ac. Pancreatitis
Increased Venous Capacitance
Anaphylaxis
Mixed of all
SEPSIS
Diagnostic Criteria
S. Na: Low if both Na+H2O, High if only H2O
BUN/ S. Creatinine raised & BUN: Creatinine ratio > 20:1
:: .. If Pre-Renal azotemia
CVP: 2 tests
Lower than normal (8 – 10 CM H2O) = In IPPV patient deduct PEEP of more than 5 cm
H2O :
Volume Challenge: 250-500 ml of rapid infusion RL/NS will increase CVP, but cannot sustain it
more than 10 minutes.
USG & IVC = correlation between
IVC size, Respiration & CVP
IVC size decreases with respiration
IVC Size Respiratory
change
CVP cm
H2O
<1.5 Total Collapse 0-5
1.5 -2.5 >50% Collapse 6-10
1.5 -2.5 < 50% Collapse 11-15
>2.5 <50% Collapse 16-20
>2.5 No Change >20
Hemorrhagic Hypovolemia: Surgical
Calculate Estimated Blood Volume (EBV): approx. 75-80 ml/ Kg
Categorize the blood loss: Fromme - Boezaart Surgical Field Grading
Boezaart AP, van der Merwe J, Coetzee A. Comparison of sodium nitroprusside- and esmolol-induced controlled hypotension for functional
endoscopic sinus surgery. Canadian Journal of Anaesthesia 1995; 42: 373-6
F-B
Grade
% age of
EBV
Fluid to be
transfused
1 - 2 Less than
10
Maintenance with
NaCl/ RL=
1ml/kg/hr
3 10 - 20 Increase the rate
of Crystalloid =
2ml/kg/hr
4 20 – 25% Colloid
5 25% or
more
Stat Blood
transfusion
Management : Non Hemorrhagic Hypovolemia
Intra-Venous Fluids : Irrespective of Na level.. Initial fluid is NS
If Na low– 0.9% N NaCl
If Hypernatremia : ½ N NaCl
Strict I/O chart with Hourly urine record
Choice of I V fluid as per I-V Compartment stay : 1 Liter
Type of fluid Intra vascular in
ml
Interstitium in ml Intra cellular in
ml
5% D/W 75-100 (10%) 230 - 260 ( 20-
23%)
670 (67%)
1 N NaCl 300 (30%) 700 (70%) 0 (0%)
1/2N NaCl 170 (17%) 500 (50%) 330 (33%)
Colloids 1000 (100%) 0 (0%) 0(0%)
According to indication
Pathology Choice of IV Fluid
Non-Hemorrhagic hypovolemic
shock
NaCl/RL/Colloids
Diarrhea RL/ NaCl
Vomiting Isolyte G, NaCl
DKA NaCl
Burns RL
Starvation 5% D/W
Maintenance Adult Isolute M
Maintenance Pediatric Isolyte P
Required Na = desired Na – actual Na x ( 0.6 x Body weight in Kg.): 0.5 females
Protocol
Impossible to measure exactly the total deficit
Empirically : RL or NaCl at the rate of 30ml/Kg bolus
RL is preferred as less chances of Hyperchloremic metabolic
acidosis
Strict watch on: vitals, CVP, Urine output, GCS, ABG
Maintain CVP 8-12cm H2O
Urine 0.5-0.6ml/kg/hr
Improved sensorium
Decreased Hematocrit and BUN: creatinine ration> 20:1
Decreased Metabolic Acidosis
SIADH
Syndrome of impaired water excretion with retention of
water leading to increase in TBW, hyponatremia but NO
CLINICAL OEDEMA
Multiple aetio-pathgeneses: stress, surgery, anesthesia,
pain, sepsis, inflammatory process, tumors, CNS
disorders
Low Na: 130, low osmolality < 270 mosm/L ,but
normovolemia
Increased urine osmolality>100mosm/L,
urine Na> 40mEq/L
Normal renal,endocrine, K levels and acid-base
balance
Correct underlying cause
Fluid restriction: < 800ml/day
Loop Diuretic
Hypertonic (3%) NaCl
High Protein diet will increase renal water
excretion
SIADH
DKA
Triad: Hyperglycemia, Dehydration and Hyperketonemia with
Metabolic acidosis
Deficit levels in DKA
Fluid deficit: 100ml/Kg---- 50% replace with NaCl (ECF)
---- 50% replace with dextrose (ICF)
Na 7-10 mEq/Kg
K 3-5 mEq/kg
PO4 5-7
Ca 1-2
Mg 1-2
ABG: severe acidosis with HCO3 grossly reduced
DKA: Management
A,B, C
Fluid Therapy
NaCl: 10-15ml/Kg/hr. up to 50ml/kg in first 4 hours
1000ml in first 30 min : next 1000 in 1hour: next 1000 in next 2
hours: next 1000 in next 2-4 hours
When Blood sugar to 250mg/dl: D5W 1000ml/ 8hourly : continue
with NaCl and D5W 1000 ml every 12 hours
Nearly 6 liters fluid in first 24 hours
Strict watch on CVP, I/O, urine, ABG(acidosis), sensorium, S. Na
levels
Strict watch On S. K levels.
DKA : Insulin
Role of Insulin: if K > 3.3 mEq/Lit
After intial NaCl infusion has started
Initial Infusion of 0.15 Unit/Kg regular = 10 units/ hr
Or Add 50 units in 50 ml NaCl
6units/hr infusion initially
Reduce to 5 units/hr when glucose < 500mg/dl
Reduce to 4 units/hr when glucose < 400 mg/dl
Reduce to 3 units/hr when glucose < 300 mg/dl
Reduce to 2 units/hr when glucose < 200 mg/dl
Maintain on 0.05-0.1unit/kg/ hr infusion
Switch over to sub cutaneous once sugar <200, HCO3 >18
DKA: Potassium Replacement
Despite total Body K deficit S.K is normal
With Volume replacement the K level drops
K <3.5 = KCl 40 mEq/L : Give 1 L of NaCl
K 3.5- 5 = KCl 20 mEq/L :Give 1 L of NaCl
K > 5 or Anuria NO KCl to be given
EKG:
Tall Ts HyperKalemia &
Flat Ts and Us HypoKalemia
DKA: HCO3
Not Recommended routinely
Only if
pH <7, Shock/ Coma, CVS/RS , Hyper Kalemia
If ABG not available:
(24 - pt’s HCO3) x (0.5 x Wt. in Kgs.)
If ABG available:
HCO3 required = BE x 1/3 of Body Wt. in Kg. & ½ correction
DKA : Supportive T/t
O2 By mask/ Venti-Mask / ETT & IPPV
CVP
N G / Urinary Catheter = I/O Balance
Colloid If MAP< 60 mmHg/ Syst BP< 90mm Hg
Antibiotics/Gastric Prophylaxis/
Mg and PO4 correction if required
Burns : Fluid Therapy
Goals:
To Maintain tissue perfusion : confirmed by hrly urine
output
To reduce the rate of catabolism or
To overcome the negative effects of Catabolism
If less than 20% burns = Oral fluids.. Exceptions facial,
hand and genital burns
If more : Parkland’s formula = total vol. in first 24 hours.
Parkland’s Formula
4ml/Kg/% burn for adult & 3ml/Kg/% burn for children
Ringer’s Lactate only
Total calculation to be transfused in first 24 hours
50%( half the volume) given in first 8 hours
Remaining 50% ( half) in next 16 hours
Children:
4 ml/kg/% burn in 0 – 10 kg
40 ml/hr + 2ml/hr for 10 – 20 kg
60 ml/ hr + 1ml/kg/hr for more than 20 kg
Next24 hours: No crystalloids, 5% Albumin (Colloid)
Up to 60% of estimated Plasma Volume
D5W as maintenance for urine: 0.5 – 1 ml/hour
Modified Parkland formula
Initial 24 hours R L 4ml/kg/ % burn
Next 24 hours Colloid infusion 5% albumin 0.3 -1
ml/kg/% burns
Parkland’s formula
Conclusion
Fluid Therapy is the ‘ Make’ or ‘Break’ for many
patients.
Especially in evolving/ imminent or existing Crisis
Understanding and executing appropriate fluid
therapy is the most essential duty of a clinician
A small oversight or miscalculation can cause a
major disaster for the patient
Continuous updating of our knowledge is most
essential
Thank You!