Fluid and electrolyte balance ih

2. Fluid and Electrolyte Balance
Presenter : Dr ITRAT HUSSAIN
Moderator : Dr. ANUJA AGARWAL

3. Daily we consume 2250 ml of water
but….
• Why do we need to drink water…
• Where does all this water go…
• Why we drink only this much of water…

4. We need to drink water because..
1 All chemical reactions occur in liquid medium.
2 It is crucial in regulating chemical and bioelectrical
distributions within cells.
3 Transports substances such as hormones and nutrients.
4 O2
transport from lungs to body cells.
5 CO2
transport in the opposite direction.
6 Dilutes toxic substances and waste products and transports
them to the kidneys and the liver.
7 Distributes heat around the body

5. Where does all this water go…
• Water constitutes an average 50 to 70% of the total body weight
Young males - 60% of total body weight
Older males – 52%
Young females – 50% of total body weight
Older females – 47%
• Variation of ±15% in both groups is normal
• Obese have 25 to 30% less body water than lean people.
• Infants 75 to 80%
- gradual physiological loss of body water
- 65% at one year of age

6. Functional Components of the Body Fluid
The water of the body is divided into 3 functional components:
(TBW – 60%)
Intracellular Fluid –
40% of the body weight
Extracellular Fluid –
20% of the body weight
Extravascular
interstitial fluid
15% of BW
Intravascular
plasma 5% of
BW
Rapidly equilibrating /
functional component
13-14% of BW
Slowly equilibrating / non-functional
component 1-2% BW
1. Connective tissue water
2. Transcellular fluid i.e. CSF, joint fluid

8. We consume only this much fluids
because…
In HOMOEOSTASIS
1. output = intake
2. Dynamic fluid equilibrium at
a) Blood & interstitial fluid
level
b) Interstitial fluid and cell
level
3. Thirst & Satiety
4. Kidney fluid control
5. Hormonal regulation

9. Dynamic Fluid Equilibrium
1. Interstitial Fluid &
cell interface
. Ion pumps &
carriers
2. Blood & interstitial
fluid interface
. Starlings forces

10. Fluid Movement Among
Compartments
• Compartmental exchange is regulated by osmotic and hydrostatic
pressures.
• Net leakage of fluid from the blood is picked up by lymphatic vessels
and returned to the bloodstream.
• Exchanges between interstitial and intracellular fluids are complex
due to the selective permeability of the cellular membranes.

11. Extracellular and Intracellular Fluids
• Ion fluxes are restricted and move selectively by active transport.
• Nutrients, respiratory gases, and wastes move unidirectionally.
• Plasma is the only fluid that circulates throughout the body and links
external and internal environments.
• Osmolalities of all body fluids are equal; changes in solute
concentrations are quickly followed by osmotic changes.

12. Thirst and Satiety
Driving force for intake ...thirst
- Baroreceptors and Osmo receptors - detectors
- ↓ of 10% plasma volume or ↑ in plasma
osmolality by 1% & Hypernatremia
↓
dry mouth
↓
impulses sent to Thirst Control Centers in the Hypothalamus which
also controls ADH release
↓
relay information to the Cerebral Cortex where thirst becomes a
conscious sensation
Urge to drink

13. Figure 26.5
Hypothalamic
Regulation

14. Kidney Regulation

16. Factors Controlling Urine Volume
1. Blood Pressure: An increase causes a greater rate of filtration
2. Increased Concentration of Salts or Glucose in Urine: These
osmotically draw more water from blood into tubules and urine.
3. Decreased Plasma Protein: failure to osmotically draw water out
of tubules into the blood
4. Vasopressin Hormone: Urine volume varies inversely to this
hormone.
5. Water Loss from Other Sources: Urine volume varies inversely
with water lost from other systems eg. perspiration or diarrhoea.
6. Diuretics

17. ADH
Regulation

18. Enhances Na+
re-absorption
(and K+
secretion)
Also stimulated by decrease in
plasma Na+
Hormonal Regulation

20. Composition of Body Fluids
• Water is the universal solvent
• Solutes
– Electrolytes – inorganic salts, all acids and bases, and
some proteins.
– Non-electrolytes –Most non electrolytes are organic
molecules – glucose, lipids,
creatinine and urea
• Electrolytes have greater osmotic power than non
electrolytes
• Water moves according to osmotic gradients

21. Electrolyte Composition of Body
Fluids
Plasma
Interstitial
fluid
Intracellular
fluid
Cations (mmol per
litre
Sodium 140 144 10
Potassium 4 4 155
Calcium 2.5 2 1
Magnesium 1 1 15
Anions (mmol per
litre)
Chloride 102 114 5
Bicarbonate 27 30 10
Phosphate 1 1 50
Sulphate 0.5 0.5 10
Protein 2 0.1 8
Organic Anions 3 6 2

22. Electrolyte Composition of Body Fluids

23. The concentration of osmotically active particles is
expressed in ‘osmoles’
• 1 mol of NaCl - 2 osm
• Osmolarity - mOsm/L
• Osmolality - mOsm/Kg water
• Osmolality defines concentration of solution
Osmotic Activity of Fluids

24. Sodium in Fluid and Electrolyte
Balance
• Normal level : 135-145mEq/L.
• It is the single most abundant electrolyte in the ECF
• Holds a central position in fluid and electrolyte balance
• It is the only electrolyte exerting significant osmotic pressure
• Sodium salts:
– Account for 90-95% of all solutes in the ECF
– Contribute 280 mOsm of the total 300 mOsm ECF solute concentration
• Regulated by dietary intake, aldosterone & kidneys

25. The Integration of Fluid Volume Regulation and
Sodium Ion Concentrations in Body Fluids

26. Sodium
imbalance
Definiti
on
Risk factors/
etiology
Clinical
manifestation
Laboratory
findings
management
Hyponatr
-aemia It is
defined
as a
plasma
sodium
level
below
135
mEq/ L
Kidney diseases
Adrenal
insufficiency
Gastrointestinal
losses
Use of diuretics
(especially with
along with low
sodium diet)
Metabolic acidosis
•Weak rapid
pulse
•Hypotension
•Dizziness
•Apprehension
and anxiety
•Abdominal
cramps
•Nausea and
vomiting
•Diarrhea
•Coma and
convulsion
•Cold clammy
skin
•Finger print
impression on
the sternum
after palpation
•Personality
change
•Serum sodium
less than
135mEq/ L
• serum
osmolality less
than
280mOsm/kg
•urine specific
gravity less
than 1.010
•Identify the
cause and treat
*Administration
of sodium orally,
by NG tube or
parenterally
*For patients who
are able to eat &
drink, sodium is
easily
accomplished
through normal
diet
*For those unable
to eat,Ringer’s
lactate solution or
isotonic saline
[0.9%Nacl]is
given
*For very low
sodium 0.3%Nacl
may be indicated
*water restriction
in case of
hypervolaemia

27. Sodium
imbalan
-ce
Definiti
on
causes Clinical
manifestation
Lab findings management
Hypernat
-remia
It is
define
d as
plasm
a
sodiu
m
level
greate
r than
145m
E
q/L
*Ingestion of
large amount
of
concentrated
salts
*Iatrogenic
administratio
n of
hypertonic
saline IV
*Excess
alderosteron
e secretion
• Low grade
fever
• Postural
hypertension
• Dry tongue
& mucous
membrane
• Agitation
• Convulsions
• Restlessness
• Excitability
• Oliguria or
anuria
• Thirst
• Dry
&flushed skin
*high serum
sodium
135mEq/L
*high serum
osmolality295
mO sm/kg
*high urine
specificity
1.030
*Administration of
hypotonic sodium
solution [0.3 or 0.45%]
*Rapid lowering of
sodium can cause
cerebral edema
*Slow administration of
IV fluids with the goal of
reducing sodium not
more than 2 mEq/L for
the first 48 hrs
decreases this risk
*Diuretics are given in
case of sodium excess
*In case of Diabetes
insipidus desmopressin
acetate nasal spray is
used
*Dietary restriction of
sodium in high risk
clients

28. Potassium BalancePotassium Balance

29. Potassium
imbalances
Definitio
n
Causes Clinical
manifestation
Lab findings Management
Hypokalemi
a
It is
defined
as
plasma
potassiu
m level
of less
than 3.0
mEq/L
*Use of
potassium
wasting
diuretic
*diarrhea,
vomiting or
other GI
losses
*Alkalosis
*Cushing’s
syndrome
*Polyuria
*Extreme
sweating
*excessive
use of
potassium
free Ivs
*weak
irregular pulse
*shallow
respiration
*hypotesion
*weakness,
decreased
bowel sounds,
heart blocks ,
paresthesia,
fatigue,
decreased
muscle tone
intestinal
obstruction
* K – less
than 3mEq/L
results in ST
depression ,
flat T wave,
taller U wave
* K – less
than 2mEq/L
cause
widened
QRS,
depressed
ST, inverted
T wave
Mild
hypokalemia[3.3to 3.5]
can be managed by oral
potassium replacement
Moderate hypokalemia
*K-3.0to 3.4mEq/L need
100to 200mEq/L of IV
potassium for the level to
rise to 1mEq/
Severe hypokalemia K-
less than 3.0mEq/L need
200to 400 mEq/L for the
level to rise to l mEq/L
*Dietary replacement of
potassium helps in
correcting the
problem[1875 to 5625
mg/day]

30. Definition Causes Clinical
manifestation
Lab findings Management
Hyperkal
emia
It is
defined
as the
elevation
of
potassiu
m level
above
5.0mEq/L
Renal failure ,
Hypertonic
dehydration,
Burns& trauma
Large amount of
IV
administration of
potassium,
Adrenal
insufficiency
Use of
potassium
retaining
diuretics &
rapid infusion of
stored blood
Irregular slow
pulse,
hypotension,
anxiety,
irritability,
paresthesia,
weakness
*High serum
potassium
5.3mEq/L
results in
peaked T
wave HR 60
to 110
*serum
potassium of
7mEq/L
results in low
broad P-
wave
*serum
potassium
levels of
8mEq/L
results in no
arterial
activity[no p-
wave]
*Dietary restriction of
potassium for potassium
less than 5.5 mEq/L
*Mild hyperkalemia can
be corrected by
improving output by
forcing fluids, giving IV
saline or potassium
wasting diuretics
*Severe hyperkalemia is
managed by
1.infusion of calcium
gluconate to decrease
the antagonistic effect of
potassium excess on
myocardium
2.infusion of insulin and
glucose or sodium
bicarbonate to promote
potassium uptake

31. Calcium
imbalan
ces
Definitio
n
Causes Clinical
manifestation
Lab
finding
s
Management
hypocal
cemia
It is a
plasma
calcium
level
below
8.5
mg/dl
•Rapid
administration of
blood containing
citrate,
•hypoalbuminemi
a,
•Hypothyroidism ,
•Vitamin
deficiency,
•neoplastic
diseases,
•pancreatitis
•Numbness
and tingling
sensation of
fingers,
•hyperactive
reflexes,
• Positve
Trousseau’s
sign, positive
chvostek’s sign
,
•muscle
cramps,
•pathological
fractures,
•prolonged
bleeding time
Serum
calciu
m less
than
4.3
mEq/L
1.Asymtomatic hypocalcemia is
treated with oral calcium
chloride, calcium gluconate or
calcium lactate
2.Tetany from acute
hypocalcemia needs IV calcium
chloride or calcium gluconate to
avoid hypotension bradycardia
and other dysrythmias
3.Chronic or mild hypocalcemia
can be treated by consumption
of food high in calcium

32. Calcium
imbalanc
e
Definition Causes Clinical
manifestation
Lab findings Management
Hypercal
cemia
It is
calcium
plasma
level over
5.5 mEq/l
or
11mg/dl
•Hyperthyro
•idism,
•Metastatic
bone tumors,
•paget’s
disease,
•osteoporosis
,
•prolonged
immobalisatio
n
•Decreased
muscle tone,
•anorexia,
•nausea,
vomiting,
•weakness ,
lethargy,
•low back pain
from kidney
stones,
•decreased
level of
consciousnes
s & cardiac
arrest
•High serum
calcium level
5.5mEq/L,
• x- ray
showing
generalized
osteoporosis,
•widened
bone
cavitation,
•urinary
stones,
•elevated BUN
25mg/100ml,
•elevated
creatinine1.5
mg/100ml
1.IV normal saline, given
rapidly with Lasix
promotes urinary
excretion of calcium
2.Plicamycin an
antitumor antibiotics
decrease the plasma
calcium level
3.Calcitonin decreases
serum calcium level
4.Corticosteroid drugs
compete with vitamin D
and decreases intestinal
absorption of calcium
5. If cause is excessive
use of calcium or vitamin
D supplements reduce
or avoid the same

33. Magnesium Balance
• Normal conc. 1.5 – 2.4 mg%
• Essential for proper functioning of enzyme systems
• Depletion characterised by neuromuscular & CNS
hyperactivity.
Mg+2
Chvostek & Trousseau sign
PR & QT interval
Treatment
if < 1.5mg% = 1 mEq/ Kg
if 1.5 – 1.8mg% = o.5mEq/ kg
Mg+2
Respiratory Depression
BP, Cardiac arrest, Hyporeflexia
Treatment
-Calcium Infusion
-Loop diuretics with NS
-MgCl2 / MgSo4

34. Solute Overview
Intracellular v/s Extracellular
• Ionic composition very different
• Total ionic concentration very similar
• Total osmotic concentrations virtually identical
Osmolarity is identical in all body fluid compartments

35. • Body control systems regulate ingestion and excretion:
- constant total body water
- constant total body osmolarity
• Homeostatic mechanisms respond to changes in ECF
• No receptors directly monitor fluid or electrolyte
balance
- Respond to changes in plasma volume or osmotic
concentrations
Principles of Body Water Distribution

36. Disorders in the fluid balance are
classified in three general categories.
Disturbances of
- Volume
- Concentration
- Composition
Classification of Body Fluid Changes

37. • Renal insufficiency, Chronic heart faliure
• Iatrogenic
• Cirrhosis
• Drugs – NSAIDS, Mineralocorticiods
• ECF is diluted – sodium content is normal but excess water is
present called as Hypotonic Hydration
• The resulting hyponatremia promotes net osmosis into tissue cells,
causing swelling.
ECF Excess

38. Disorders of Water Balance:
Hypotonic Hydration
Excessive H2O enters
the ECF
1 2 ECF osmotic
pressure falls
3 H2O moves into
cells by osmosis;
cells swell

39. ECF Deficit
CAUSES
1. Loss of GI fluids due to:
a. Vomiting
b. Diarrhea
c. Nasogastric suction
d. Fistular drainage
2. Soft tissue injuries and infections
3. Intraabdominal and Intraperitoneal
inflammatory processes
4. Burns
5. Insensible losses
6. Sweat

40. Dehydration
Excessive loss of H2O from
ECF
1 2 3ECF osmotic
pressure rises
Cells lose H2O
to ECF by
osmosis; cells
shrink
ECF Deficit : When salt depletion is greater, fluid loss is borne by ECF
Lab Test: Hematocrit value of 45% indicates an ECF deficit.
ICF Deficit : When water depletion is predominant, the greatest fluid loss is
sustained by the intracellular compartment
Lab Test :The sodium concentration is an indirect measure of the fluid.
Higher sodium value indicates an ICF Deficit

41. Clinical Evaluation
Changes in body weight should be recorded accurately and
repeatedly on a day to day basis….
Weight loss > 300 to 500gms per day indicate dehydration
secondary to decreased fluid intake and / or increased
water losses.
Water loss Degree of Dehydration
4% of body wt Mild
6% “ “ Moderate
8% “ “ Severe

42. Principles of Fluid Therapy
Whenever fluid therapy is contemplated in a
patient, the following basic questions must be
considered….
1. Does the patient need fluid..?
2. Which fluid would be most suitable..?
3. How much fluid is needed..?
4. At what rate..?
5. Which route is to be used..?
6. What are the likely complications..?

43. Does the Patient Need Fluids..
– Pre-existing disease processes
• Cancer, cardiovascular, renal, GI
– Age
• Infants have higher % water- loss felt faster
• Elderly –kidneys decreased filtration rate, less functioning
nephrons, don’t excrete medications as fast
– Acute illness
• Surgery, burns, respiratory disorders, head injury
– Environmental
• Vigorous exercise, temperature extremes
– Diet
• Fluids and electrolytes gained through diet
– Medications
• Side-effects may cause fluid and/or electrolyte imbalances

44. Medications Likely to Cause
F&E Imbalances
• Diuretics
– Metabolic alkalosis, hyperkalemia,hyponatremia.
• Steroids
– Metabolic alkalosis
• Potassium supplements
– GI disturbances
• Respiratory center depressants (narcotic analgesics)
– Respiratory acidosis
• Antibiotics
– Nephrotoxicity, hyperkalemia, hypernatremia
• Calcium carbonate
– Metabolic alkalosis
• Magnesium hydroxide (Milk of Mag)
– hypokalemia

45. Diagnostics
• Hematocrit
– If no anemia, can indicate hydration status
• Blood creatinine
– Measure kidney function
• Excreted at constant level if no kidney disease
• BUN
– Indicates kidney function
• May be affected by cell destruction or steroid therapy
– Decrease may indicate malnutrition or hepatic
damage
– Increases with decrease in ECF volume
• Serum and urinary electrolyte levels
• Urine specific gravity

46. Assessment of Intravascular
Depletion
• 5% thirst, dry mucous membranes,
UO 1-2 ml/kg/hr
• 10% tachycardia, oliguria,
UO 0.5-1 ml/kg/hr
• 15%-20% tachycardia, hypotension,
severe oliguria,
UO < 0.5 ml/kg/hr

47. What Fluids to Give..What Fluids to Give..
• Choice of a particular fluid depends on
– Volume status
– Concentration abnormality
– Compositional abnormality
• Crystalloids:Crystalloids:
- contain Na as the main osmotically active particle
- useful for volume expansion (mainly interstitial space)
- for maintenance infusion
- correction of electrolyte abnormality

48. CrystalloidsCrystalloids
• Isotonic crystalloids
- Lactated Ringer’s, 0.9% NaCl
- only 25% remain intravascularly
• Hypertonic saline solutions
- 3% NaCl
- 7% NaCl
• Hypotonic solutions
- 0.45% NaCl
- less than 10% remain intra-
vascularly, inadequate for fluid
resuscitation

49. Colloid SolutionsColloid Solutions
• Contain high molecular weight
substancesdo not readily migrate across
capillary walls
• Preparations
- Albumin: 5%, 25%
- Dextran
- Gelifundol
- Hetastarch

50. Crystalliod Colloid
Intravascular persistance Poor Good
Haemodynamic stabilisation
Transient
t1/2 ~ 30 mins
Prolonged
t1/2 ~ 90 mins
Required infusion volume
Large
Ratio 4:1 to loss
Moderate
Ratio 2:1 to loss
Risk of tissue oedema Obvious Insignificant
Enhancement of capillary perfusion Poor Good
Risk of anaphylaxis Nil Low to moderate
Plasma colloid osmotic pressure Reduced Maintained
Cost
Inexpensive Expensive
Crystalloids and Colloids

51. • Oral electrolyte solution:
This solution is isotonic and provides a rich source of Na+
, K+
, Cl-
and
dextrose. The sodium citrate tends to correct any acidosis.
• IV fluids:
0.9% Sodium Chloride
- iso osmolar with plasma
- serves a good replacement solution for ECF volume
- chloride content - higher than that of plasma infusion →
too much of normal saline may produce
hyperchloraemic acidosis
- indication : ECF def in the presence of hypernatremia,
hypochloremia & metabolic alkylosis…
What solution to give…

52. Dextrose 5% in Water
• It provides 50gms of dextrose / L.
• slightly hypertonic to plasma
• after infusion dextrose is metabolized→ water is left in the ECF…
• too much of 5% dextrose may cause dilution and hypotonicity of ECF
and water loading, if kidneys are not functioning normally.
Dextrose 5% with 0.9% Saline.
• Its twice as hypertonic as plasma…
• However within a few hours glucose is used and there is no
significant change in the plasma tonicity…

53. Lactated Ringers Solution.
• This is slightly hypo osmolar compared to plasma
• Minimum effect on pH & normal body fluid composition
• Replaces both G.I. & ECF losses
• Used in correcting metabolic acidosis….
• Should not be given in patients with liver diseases and in
presence of lactic acidosis.
Ringers Acetate Solution.
- slightly hypo osmolar to plasma…
- main use is as a replacement for ECF deficits in patients with
damaged liver or lactic acidosis..
- helps in correction of mild to moderate metabolic acidosis.

54. 0.45% Sodium Chloride in 5% Dextrose Solution
- It is used as maintenance fluid in postoperative period.
- Provides sodium for renal adjustment of sodium concentration in the
serum.
- Potassium may be added to be used for maintenance requirements in
uncomplicated pt requiring only a short period of parenteral fluids.
7.2-7.5 % Sodium Chloride
- Studies have shown that even with 50% blood loss, a small volume of
7.2-7.5% NaCl restores the cardiac output and blood pressure within
one minute.
- This saline is given through a peripheral vein very fast over 2 to 5 mins.
And this results in rise in the plasma sodium level and plasma
osmolality causing a shift of body water in the vascular tree

55. Composition of Parental Fluids
(Electrolytes Content,
mEeq/L)

56. Practical Crystalloid Therapy
• If you infuse NaCl 0.9% 1000ml, all the Na+
will remain in the
ECF
• As NaCl is isotonic there is no change in ECF osmolality and
no water exchange occurs across the cell membrane
• NaCl expands ECF only
• Intravascular volume will be increased by 250ml

57. Practical Crystalloid Therapy
• If you infuse glucose 5% 1000ml, the glucose will enter the cell
and be metabolised
• The water expands both ECF and ICF in proportion to their
volumes
• The ECF volume will increase by 333ml
• Intravascular volume will only increase by approximately 100ml

58. Colloid Solutions
Human Plasma
- Used for resuscitation of shock patient and for
maintenance of I.V. fluid therapy
- It has a composition and osmolality similar to ECF.
Human Albumin
- 20% purified human albumin is commercially available. Its volume
expansion capacity is 400 per cent.
- Rarely, anaphylactoid reaction has been reported with albumin and
may cause post resuscitation hypotension.

59. Hetastarch
• Mixture of derivatized amylopectin of various mol. Wt.
• Derivatization increases resistance to enzymatic hydrolysis
• Vol. expansion ~ 100 – 172 % of infused volume
- seen for 24 – 36 hrs.
Dextran
• It’s a polysaccharide in 0.9% NaCl / 5% Dextrose
• Two types
» 40 – lasts for 6 hrs
» 70 – lasts for 24 hrs
• Facilitates agglutination of RBC. Thus interferes with
susequent cross matching of blood

60. The Influence of Colloid & CrystalloidThe Influence of Colloid & Crystalloid
on Blood Volumeon Blood Volume
1000cc1000cc
500cc500cc
500cc500cc
500cc500cc
200200 600600 10001000
Lactated RingersLactated Ringers
5% Albumin5% Albumin
6% Hetastarch6% Hetastarch
Whole bloodWhole blood
Blood volumeBlood volume
Infusion
volume
Infusion
volume

61. • As in normal health - 0ral Route.
- However when rapid correction of hypovolaemia and
other electrolyte abnormalities indicated i.v. route
provides a quick access to circulation.
- Other routes of parenteral therapy include
- Subcutaneous
- Per Rectal
What Route to be Used..

62. What Rate to be Used..
• Standard recommendation for calculation of Hourly maintenance of
Fluid Replacement are :
0 – 10 Kg 4 ml / kg
11 – 20 Kg 2 ml / Kg
> 20 kg 1 ml / kg
So in a 70 Kg person
( 4×10 ) + ( 2 ×10 ) + ( 1× 50 ) = 110 ml/ hr

63. Fluid Balance in Pre Op. Period
1. Correct 3rd
space losses
2. Correct Na+
balance
3. K+
to be corrected only when adequate urine output
maintained
4. Check if blood replacement is required
5. Calculate Allowable Blood Loss
6. Prevention of volume depletion

64. Third Space Losses
• Isotonic transfer of ECF from functional body fluid
compartments to non-functional compartments.
• Depends on location and duration of surgical procedure,
amount of tissue trauma, ambient temperature, room
ventilation
• Replacement of 3rd
space losses
Minimum trauma : 3 – 4 ml / kg / hr
Moderate trauma : 5- 6 ml / kg /hr
Severe trauma : 7 – 8 ml / kg / hr
• Surgeon must remember that by 72 hours post op., this 3rd
space loss becomes mobilised which results in increased
intravascular volume

65. Intra Op. Fluid Management
• If pre-op. volume deficit not addressed --- hypotension
• 3rd
space losses to be addressed because of
» Tissue Trauma
» Extensive Dissection
» May vary from min. to 3 Lt.
• But no lab methods to exactly quantify fluid loss
• So, clinically useful guidelines are
1. Replacement of ECF should begin intra op.
2. Blood should be replaced to maintain an acceptable RBC
mass irrespective of any additional fluid/ electrolyte therapy
3. Balanced salt sol. needed intra op. ~ 0.5 – 1 Lt/ hr.
Only max. of 3 Lt. req. during 4 hr major abdominal surgery

66. Post Op. Fluid Management
0 – 24 hrs.
• Increased secretion of aldosterone & ADH
» Na+
& water retention
• If blood loss is there, replace it
• Replace NPO fluid deficit
» DNS or RL
• Should not administer K+
unless definitive deficiency
present

67. 24 – 48 hrs.
• Replace insensible losses which may vary from
900 – 1500 ml/ hr because of
- Hyper Ventilation
- Fever
- Tracheostomy – upto 1200 ml/ day
• Loss replaced by DNS since kidneys conserve Na+
even
at this stage .
• If N-G aspiration is going on then add 1 Lt. of 0.9 NaCl

68. 48 – 72 hrs.
• Replace insensible losses
• Better to give isotonic DNS & RL
• 1 Lt Darrow’s solution to combat K+
loss. This is more
important if N-G aspiration is still going on to cover K+
loss via GI secretions
Importance of I/O charts
Output = urine + vomitus + aspiration
+ 1000 ml insensible losses
+ 500 – 1000 ml sweating loss
Total this has
to be
replaced

69. Post Op. Urine Output
• Oliguria is common in immediate post op. period because
1. Surgical stress – affects Adrenal Cortex
- increase ADH & Aldosterone
2. Insufficient post op. analgesia – sympathetic activity increased
3. General anesthetics decrease glomerular blood flow & thus GFR
• Persistent oliguria
– < 20 ml / hr in adults
– < 1 ml / hr / kg in children
• If urine output < 0.5 ml / hr / kg for 3 or more hrs.– indicative
of ARF.
Hypovolemia

70. • Monitoring urine output, heart rate, BP on repeated basis and
comparing them to measure fluid intake assists in determining fluid
requirement ….
• Normal urinary output
Adult 0.5-1 ml / kg / hr
Child 2 ml / kg / hr
End Parameters for Fluid
Replacement Therapy

71. Fluid Regulation in Young
• Fluid balance in young is dicey because…
• In neonates most significant source of water loss is
insensible water loss through skin ~ 7ml / kg / hr
• Under normal renal function
• Infants & neonates – 2 ml / kg
• Toddlers & school age – 1 ml / kg
• Daily K+
req. = 2mEq/ kg
Na+
req. = 3 mEq/ kg
• Maintenance fluid rate
 0 – 10 kg - 4 ml / kg / hr
10 – 20 kg - 40 ml + 2 ml / kg / hr
 > 20 kg - 60 ml + 1 ml / kg / hr

72. Blood Replacements
Blood weightage – males 66 ml / kg
- females 60 ml / kg
Indications
1. If Hb. < 6 gm%
2. Ongoing fluid loss of 100 ml/ hr
3. ACS Class IV Haemorrhage
4. Give early in active bleeding
Hemodilution
• Indicated in surgeries where intra op. blood loss of 2 or
more units is anticipated
• plasma volume restoration with crystalloids/ colloids
• Blood reinfused only after cessation of bleeding

73. ShockShock
Pathophysiology, Classification, andPathophysiology, Classification, and
Approach to ManagementApproach to Management

74. Shock: DefinitionShock: Definition
Kumar and Parrillo (1995) - “The state in which profound
and widespread reduction of effective tissue perfusion
leads first to reversible, and then if prolonged, to
irreversible cellular injury.”

75. Classification of Circulatory ShockClassification of Circulatory Shock
HYPOVOLEMIC
Hemorrhagic
• Trauma
• Gastrointestinal
• Retroperitoneal
Fluid depletion (nonhemorrhagic)
• External fluid loss
- Dehydration
- Vomiting
- Diarrhea
- Polyuria
• Interstitial fluid redistribution
- Thermal injury
- Trauma
- Anaphylaxis
Increased vascular capacitance (venodilatation)
• Sepsis
• Anaphylaxis
• Toxins/drugs

76. CARDIOGENIC
Myopathic
• Myocardial infarction (hibernating myocardium)
• Left ventricle
Right ventricle
Myocardial contusion (trauma)
Myocarditis
Cardiomyopathy
Septic myocardial depression
Pharmacologic
• Calcium channel blockers
Mechanical
• Valvular failure (stenotic or regurgitant)
• Hypertropic cardiomyopathy
• Ventricular septal defect
Arrhythmic
• Bradycardia
• Tachycardia
•
Classification of Circulatory ShockClassification of Circulatory Shock

77. Classification of Circulatory ShockClassification of Circulatory Shock
EXTRACARDIAC OBSTRUCTIVE
Impaired diastolic filling (decreased ventricular preload)
• Direct venous obstruction (vena cava)
• Increased intrathoracic pressure
- Tension pneumothorax
- Mechanical ventilation (with excessive pressure or volume depletion)
- Asthma
• Decreased cardiac compliance
- Constrictive pericarditis
- Cardiac tamponade
Impaired systolic contraction (increased ventricular afterload)
• Right ventricle
- Pulmonary embolus (massive)
- Acute pulmonary hypertension
• Left ventricle
- Saddle embolus
- Aortic dissection

78. Classification of Circulatory ShockClassification of Circulatory Shock
DISTRIBUTIVE
Septic (bacterial, fungal, viral, rickettsial)
Toxic shock syndrome
Anaphylactic, anaphylactoid
Neurogenic (spinal shock)
Endocrinologic
• Adrenal crisis
• Thyroid storm
Toxic (e.g., nitroprusside, bretylium)

79. TABLE I: CLASSIFICATION OF SHOCK (based on a 70 kg patient)
CLASS (mL) up to 750 750-1500 1500-2000 2000 or more
Blood Loss (%BV) up to 15% 15-30% 30-40% 40% or more
Pulse Rate <100 >100 >120 140 or higher
Blood Pressure Normal Normal Decreased Decreased
Pulse Pressure Normal/Increased Decreased Decreased Decreased
Capillary Refill Normal Decreased Decreased Decreased
Respiratory Rate 14-20 20-30 30-40 >35
Urine Output (mL/hr) 30 or more 20-30 5-15 Negligible
CNS-Mental Status Slightly-anxious Anxious Anxious - Confused-
confused lethargic
Fluid Replacement Crystalloid Crystalloid Crystalloid Crystalloid
+ blood + blood
(Modified from: Committee on Trauma of the American College of Surgeons.

82. Initial Therapeutic StepsInitial Therapeutic Steps
A Clinical Approach to ShockA Clinical Approach to Shock
Diagnosis and ManagementDiagnosis and Management
Admit to intensive care unit (ICU)
Venous access (1 or 2 wide-bore catheters)
Central venous catheter
Arterial catheter
ECG monitoring
Pulse oximetry
Hemodynamic support (MAP < 60 mmHg)
• Fluid challenge
• Vasopressors for severe shock unresponsive to fluids

83. Conclusion
I.V fluids should be administered with caution
Input-output chart should me maintained
Electrolyte level should be monitored.
The maximum volume is the least volume
needed.

84. References
• Clinics in Endocrinology and Metabolism – D. Brian Morgan.
• Principles of Surgery – Schwartz
• Principles of Surgery – Sabiston
• Essentials of Human Anatomy & Physiology – Marieb
• Human Physiology – Guyton and Hall
• Oral & MaxilloFacial Sugery Clinics of North America – HarryDym

85. Thank you…