• ELECTROLYTE BALANCE • Def: - concentration of individual electrolytes in the body fluid compartments is normal and remains relatively constant. • Electrolytes are dissolved in body fluids • Sodium predominant extracellular cation, and chloride is predominant extracellular anion. Bicarbonate also in extracellular spaces • Electrolyte balance • Na + (Sodium) – 90 % of total ECF cations – 136 -145 mEq / L – Pairs with Cl- , HCO3- to neutralize charge – Low in ICF – Most important ion in regulating water balance – Important in nerve and muscle function • Electrolyte imbalances: Sodium • Hypernatremia (high levels of sodium) – Plasma Na+ > 145 mEq / L – Due to ↑ Na + or ↓ water – Water moves from ICF → ECF – Cells dehydrate • HYPERATREMIA • Hypernatremia Due to: – Hypertonic IV soln. – Oversecretion of aldosterone – Loss of pure water • Long term sweating with chronic fever • Respiratory infection → water vapor loss • Diabetes – polyuria – Insufficient intake of water . • Clinical manifestations of Hypernatremia • Thirst • Lethargy • Neurological dysfunction due to dehydration of brain cells • Decreased vascular volume • TREATMENT OF HYPERNATREMIA: • Lower serum Na+ – Isotonic salt-free IV fluid [5% dextrose] – Oral solutions preferable • Hyponatremia • Overall decrease in Na+ in ECF • Two types: depletional and dilutional • Depletional Hyponatremia Na+ loss: – diuretics, chronic vomiting – Chronic diarrhea – Decreased aldosterone – Decreased Na+ intake • Clinical manifestations of Hyponatremia • Neurological symptoms – Lethargy, headache, confusion, apprehension, depressed reflexes, seizures and coma • Muscle symptoms – Cramps, weakness, fatigue • Gastrointestinal symptoms – Nausea, vomiting, abdominal cramps, and diarrhea • Tx – limit water intake or • discontinue medicines such as diuretics • TREATMENT OF HYPONATREMIA • Hyponatremia which develops quickly should be treated quickly & vice-versa • Patients with severe hypoNa (<115) are at risk of neurological damage • Too rapid correction causes CENTRAL PONTINE MYELINOLYSIS. • Targeted rate of correction: 0.5-1.0 mEq/L/hour • Raise plasma Na by <10-12 mEq/L on first day • Correction @ rate >25mEq/L places at high risk for central pontine myelinolysis • Hypokalemia • Normal serum k+ conc is 3.5 to 5.0 mEq/l • Serum K+ < 3.5 mEq /L • Beware if diabetic – Insulin gets K+ into cell – Ketoacidosis – H+ replaces K+, which is lost in urine • β – adrenergic drugs or epinephrine • Causes of Hypokalemia • Decreased intake of K+ • Increased K+ loss – Chronic diuretics – Acid/base imbalance – Trauma and stress – Increased aldosterone – Redistribution between ICF and ECF • Treatment of hypokalamia • Metabolic acidosis increases serum K+ levels & vice versa • Post-op patients on fluid therapy should receive approx 60mEq/day to prevent hypokalemia • 1mEq/L fall in serum K+= 200-400 mEq total body K+ deficit • Failure to ↑ Sr. K+ even after sufficient correction should

1. FLUID AND ELECTROLYTE
BALANCE
By
Dr. Punam Nagargoje

2. • DISTRIBUTION OF BODY WATER
• TYPES OF SOLUTION
• BODY FLUID MOVEMENT
• HOMEOSTASIS
• TONICITY
• WATER BALANCE
• ELECTROLYTE BALANCE
• ACID-BASE BALANCE
• DISTURBANCES
• FLUID THERPY

3. DISTRIBUTION OF BODY FLUIDS
2/3 (40%) of TBW is intracellular (ICF)
1/3 extracellular water
-15% interstitial fluid (ISF)
-5- 8 % in plasma (IVF intravascular
fluid)
1- 2 % in transcellular fluids – CSF,
intraocular fluids, serous membranes,
and in GI, respiratory and urinary
tracts (third space)

4. DISTRIBUTION OF BODY FLUIDS

5. DAILY INTAKE AND OUTPUT OF WATER

6. MOVEMENTS OF BODY WATER
Diffusion – movement of particles down a
concentration gradient.
Osmosis – diffusion of water across a
selectively permeable membrane
Active transport – movement of particles
up a concentration gradient ; requires
energy

7. PLASMA OSMOLALITY
• Plasma Osmolality
2 × Na + Glucose (mg/dl) + BUN (mg/dl)
18 2.8
• Normal plasma osmolality is between 275-285
mOsm/Kg
• Generally, plasma sodium concentration is
determinant and reflector of plasma
osmolality

8. CRYSTALLOIDS AND COLLOIDS
• Fluids with small “crystalizable” particles like
NaCl are called CRYSTALLOIDS.
• Fluids with large particles like albumin are
called COLLOIDS, these don’t (quickly) fit
through vascular pores, so they stay in the
circulation and much smaller amounts can be
used for same volume expansion. (250ml
Albumin = 4 L NS)
• Edema resulting from these also tends to stick
around longer for same reason.
• Albumin can also trigger anaphylaxis.

9. 5% DEXTROSE
Glucose 50gms
170 kcal/L
Corrects intracellular dehydration & supplies energy
Used for:
Prevention & Rx of dehydration d/t water loss
Pre & post op fluid replacement
Vehicle for drugs
Prevention & Rx of ketosis
Correction of hyperNa+ d/t pure water loss
Contraindications
Cerebral oedema
Hypovolemic shock
With Blood transfusion
HypoNa+ & water intoxication
Uncontrolled DM/ Hyperglycemia
Administer @ 0.5 g/kg/hour
Rule out glycosuria and associated fluid loss d/t
osmotic diuresis
NORMAL SALINE
Na 154 Cl 154
100ml contains NaCl = 0.90 gm
Useful in correcting both fluid &
electrolyte deficit
Used for:
Water & salt depletion
Rx of hypovolemic shock
Rx of alkalosis with dehydration
Rx of hypercalcemia
Rx of salt depletion/hyponatremia
Irrigation fluid
Vehicle for drugs
Can be given safely with blood
Contraindications
Preeclampsia/ HTN
Oedema d/t CCF, ARF, Cirrhosis
Dehydration with severe hypokalemia

10. DNS
Glucose 50 gm Na 154 Cl 154
100 ml = 5gm Glucose & 0.9 gm NaCl
Useful in supplying major ECF electrolytes &
energy along with fluid to correct dehydration
Used for
Correction of salt depletion & hypovolemia with
supply of energy
Correction of vomiting/NG aspiration induced
alkalosis & hypochloremia along with supply of
calories
Compatible with BT
Contraindications
Anasarca
Hypovolemic shock (Rapid infusion causes
hyperglycemia & osmotic diuresis even in
presence of fluid deficit)
ISOLYTE- P
Glucose 50g Na 25
mEq
Acetate 23 mEq Cl 22 mEq
K 20 mEq Mg 3
mEq
HPO4 3 mEq
Designed to suit maintenance fluid
requirement of CHILDREN
Provides electrolytes, maintains pH,
supplies calories & replaces water
deficit
Used chiefly as maintenance fluid in
infants & children and in Diabetes
insipidus in adults
Contraindicated in hyponatremia and
in renal failure ( high conc of
potassium)
Not to be used in hypovolemic shock

11. RINGER’S LACTATE (RL)
• Na+ = 130 K+ = 4
• Cl+ = 109 Ca++ = 3
• HCO3
- = 28
• Most physiological of all fluids as its
electrolyte content similar to free
concentration in plasma
• Lactate converted to bicarbonate in liver.
Used in:
• Correction of severe hypovolemia
• Replacement fluid in post-op, burns, etc.
• Diarrhoea induced hypovolemia with
hypokalemic metabolic acidosis
• DKA
• As maintainence fluid intraop
Contraindications
Liver disease
Renal failure
Severe CCF
Addison’s disease
Severe metabolic acidosis
Vomiting or continuous NG aspiration
Along with BT
Ca in RL binds with certain drugs to
reduce their bioavailability ( AMB,
Thiopental, Ampicillin)

12. NAHCO3
• Inj. Soda bicarb 7.5%, 25 mL ampoule contains 22.5mEq Na and 22.5mEq HCO3
Indications
• Metabolic acidosis -CPCR and Shock
• Hyperkalemia -Alkaline forced diuresis
• Amt of NaHCO3= 1/3 × Weight (kg) × Bicarb deficit
• 50% of this IV bolus and rest 50% over a period of 4 hours in severe metabolic
acidosis
• DO NOT CORRECT metabolic acidosis rapidly or completely (Target Bicarb= 15-20
mEq/L)
• Extravasation causes thrombophlebitis
• Never treat acidosis without treating etiology
• Never correct acidosis without correcting associated HypoK+
• In ARF, bicarb may cause pulmonary edema or tetany
• Do not mix Ca. gluconate in same syringe
• Avoid mixing with ionotropes
• Aggressive Rx may lead to volume overload
• Cautious use in CCF, CRF, ALD, HTN.

13. KCl
• Inj KCl 15% 10 mL ampoule contains 20mEq K+ or 1.5 gm KCl
• Although chief intracellular cation, required in ECF for
neuromuscular regulation
Indications
• Prevention of hypoK+ in patient on maintenance fluid & Rx
of hypokalemia
• Added to potassium free peritoneal dialysis
• During CABG to achieve cardiac standstill
Precautions
• Never give direct I/V, always diluted infusion
• Never add more than 40 mEq/litre
• Never infuse more than 10 mEq/hour
• Monitor serum K+ level closely & also by ECG
Contraindications
• CRF

14. COLLOIDS
• ALBUMIN
• DEXTRAN (DEXTRAN 70 & DEXTRAN 40)
• GELATIN POLYMERS (HAEMACCEL)
• HETASTARCH (HYDROXYETHYL STARCH)
• PENTASTARCH

15. ALBUMIN
• Physiological plasma protein whose chief function is to maintain
plasma oncotic pressure
• 5% solution (50g/L) or 25% solution (250g/L)
• 5% solution has colloid osmotic pressure of 20mmHg & expands
plasma to roughly same vol. infused with effects lasting 12-18 hrs
whereas 25% solution has pressure of 70 mmHg & expands plasma
4-5 times with effects lasting 16-20 hrs.
• Expansion occurs at expense of ISF hence not to be used in
hypovolemic patients
Indications
• Plasma volume expansion
• Correction of hypoproteinemia in short-term
• Therapeutic plasmapheresis as exchange fluid
Contraindications
• CCF
• Severe Anaemia and severe dehydration
Adverse effects may include allergic reactions
• Suggested rate: 1-2 mL/minute

16. DEXTRAN
• Glucose polymers produced by bacteria incubated in sucrose medium
• M.W. 70,000 and 40,000 (Dextran 70 & 40)
• Used for plasma volume expansion as well as for improvement of
microcirculation & prevention of thrombo-embolism
Indications
• Correction of hypovolemia
• Prophylaxis of DVT and Post-op & post-traumatic thromboembolism
• Improve blood flow & micro-circulation in threatened vascular gangrene
• Adverse effects include allergic reactions, ARF, interference with BG/CM
Contraindications
• Severe oliguria & ARF
• CCF
• Hypersensitivity
• Bleeding disorders like TTP, hypofibrinogenemia
Precautions
• Hct should not be allowed to fall below 30%
• Anticoagulant effect of Heparin is enhanced by Lomodex
• Correct dehydration before use
• Samples for BGCM to be collected before infusion

17. FLUID INFUSION RATE
• MACRO DRIP 1mL = 15 DROPS
• MICRO DRIP 1mL = 60 DROPS
• RULE OF TEN
IV FLUID IN LITRE/24 HRS × 10 = DROP RATE/MIN
• RULE OF FOUR
VOLUME IN mL/HOUR ÷ 4 = DROP RATE/MIN
• DROP RATE CALCULATION
VOLUME TO BE INFUSED (IN mL)_____ = DROP RATE
DURATION OF INFUSION IN HOURS × 4 PER MIN.

18. Tonicity
Isotonic –NS,RL,Albumin
Hypertonic – Hypertonic saline
Hypotonic – ½ NS

19. WATER REGULATION
• ADH – antidiuretic hormone + thirst
– Decreased amount of water in body
– Increased amount of Na+ in the body
– Increased blood osmolality
– Decreased circulating blood volume
• Stimulate osmoreceptors in hypothalamus
ADH released from posterior pituitary
Increased thirst

20. Result:
increased water consumption
increased water conservation
Increased water in body, increased
volume and decreased Na+ concentration
Dysfunction or trauma can cause:
Decreased amount of water in body
Increased amount of Na+ in the body
Increased blood osmolality
Decreased circulating blood volume

21. Solutes – dissolved particles
• Electrolytes – charged particles
–Cations – positively charged ions
• Na+, K+ , Ca++, H+
–Anions – negatively charged ions
• Cl-, HCO3
- , PO4
3-
• Non-electrolytes - Uncharged
• Proteins, urea, glucose, O2, CO2

22. ELECTROLYTE BALANCE
• Def: - concentration of individual electrolytes
in the body fluid compartments is normal and
remains relatively constant.
• Electrolytes are dissolved in body fluids
• Sodium predominant extracellular cation, and
chloride is predominant extracellular anion.
Bicarbonate also in extracellular spaces

23. Potassium is the predominant intracellular cation
and phosphates are the predominant intracellular
anion
Cations are actively reabsorbed, anions passively
follow by electrochemical attraction
Aldosterone works at kidney tubules to regulate
sodium & potassium levels

24. Electrolyte balance
• Na + (Sodium)
– 90 % of total ECF cations
– 136 -145 mEq / L
– Pairs with Cl- , HCO3
- to neutralize charge
– Low in ICF
– Most important ion in regulating water balance
– Important in nerve and muscle function

25. • Hypernatremia (high levels of sodium)
–Plasma Na+ > 145 mEq / L
–Due to ↑ Na + or ↓ water
–Water moves from ICF → ECF
–Cells dehydrate
Electrolyte imbalances: Sodium

26. HYPERATREMIA
• Hypernatremia Due to:
–Hypertonic IV soln.
–Oversecretion of aldosterone
–Loss of pure water
• Long term sweating with chronic fever
• Respiratory infection → water vapor loss
• Diabetes – polyuria
–Insufficient intake of water .

27. Clinical manifestations
of Hypernatremia
• Thirst
• Lethargy
• Neurological dysfunction due to dehydration
of brain cells
• Decreased vascular volume
• TREATMENT OF HYPERNATREMIA:
• Lower serum Na+
–Isotonic salt-free IV fluid [5% dextrose]
–Oral solutions preferable

28. Hyponatremia
• Overall decrease in Na+ in ECF
• Two types: depletional and dilutional
• Depletional Hyponatremia
Na+ loss:
– diuretics, chronic vomiting
– Chronic diarrhea
– Decreased aldosterone
– Decreased Na+ intake

29. Dilutional Hyponatremia:
Renal dysfunction with ↑ intake of
hypotonic fluids
Excessive sweating→ increased thirst →
intake of excessive amounts of pure
water
Syndrome of Inappropriate ADH (SIADH)
or oliguric renal failure, severe
congestive heart failure, cirrhosis all
lead to:
Impaired renal excretion of water
Hyperglycemia – attracts water

30. Clinical manifestations of
Hyponatremia
• Neurological symptoms
– Lethargy, headache, confusion, apprehension,
depressed reflexes, seizures and coma
• Muscle symptoms
– Cramps, weakness, fatigue
• Gastrointestinal symptoms
– Nausea, vomiting, abdominal cramps, and diarrhea
• Tx – limit water intake or
• discontinue medicines such as diuretics

31. TREATMENT OF HYPONATREMIA
• Hyponatremia which develops quickly should be treated
quickly & vice-versa
• Patients with severe hypoNa (<115) are at risk of
neurological damage
• Too rapid correction causes CENTRAL PONTINE
MYELINOLYSIS.
• Targeted rate of correction: 0.5-1.0 mEq/L/hour
• Raise plasma Na by <10-12 mEq/L on first day
• Correction @ rate >25mEq/L places at high risk for central
pontine myelinolysis

32. Stop Rx once any of foll. end-points reached:
-Symptoms resolved
-Safe plasma Na achieved (125-130 mEq/L)
-Total magnitude of correction of 20 mEq/L is
achieved
NS or 3%NaCl may be used depending on type
& severity of hyponatremia

33. Hypokalemia
• Normal serum k+ conc is 3.5 to 5.0 mEq/l
• Serum K+ < 3.5 mEq /L
• Beware if diabetic
–Insulin gets K+ into cell
–Ketoacidosis – H+ replaces K+, which is lost
in urine
• β – adrenergic drugs or epinephrine

34. Causes of Hypokalemia
• Decreased intake of K+
• Increased K+ loss
–Chronic diuretics
–Acid/base imbalance
–Trauma and stress
–Increased aldosterone
–Redistribution between ICF and ECF

35. Treatment of hypokalamia
• Metabolic acidosis increases serum K+ levels & vice versa
• Post-op patients on fluid therapy should receive approx
60mEq/day to prevent hypokalemia
• 1mEq/L fall in serum K+= 200-400 mEq total body K+ deficit
• Failure to ↑ Sr. K+ even after sufficient correction should
raise the possibility of associated Mg++ deficiency.
• KCl is generally used as it corrects hypokalemia as well as
metabolic alkalosis
• ECG & Sr. K+ monitoring must to avoid hyperK+ (Remember
hypokalemia safer than hyperkalemia)

36. • Oral supplementation can be used in mild hypoK
(Syp. Kesol as 20mEq per 15 mL solution)
• Avoid D5% with KCl → aggravates hypokalemia
• K+ conc. > 40 mEq/L can cause phlebitis
• Avg rise in K+ level is 0.25 mEq/L when 20 mEq/L is
given in one hour
• To be given till cardiac rhythm/respiratory muscle
strength restored to normal

37. Hyperkalemia
• Serum K+ > 5.5 mEq / L
• Check for renal disease
• Massive cellular trauma
• Insulin deficiency
• Addison’s disease

38. Hyperkalemia
• Potassium sparing diuretics
• Decreased blood pH
• Exercise causes K+ to move out of cells

39. Clinical manifestations of
Hyperkalemia
• Early – hyperactive muscles , paresthesia
• Late - Muscle weakness, flaccid paralysis
• Change in ECG pattern
• Dysrhythmias
• Bradycardia , heart block, cardiac arrest

40. Treatment of Hyperkalemia
• Stop exogenous k adminstration
• Rx underlying cause
• Reverse cardiotoxic effects
• 1 gm ca gluconate with ECG monitoring
• Rapid alkalisation of ECF by lactate/HCO3
• Cation exchange resins.
• Peritonial dialysis/hemodilysis

41. Calcium Imbalances
• Most in ECF
• Regulated by:
–Parathyroid hormone
• ↑Blood Ca++ by stimulating osteoclasts
• ↑GI absorption and renal retention
–Calcitonin from the thyroid gland
• Promotes bone formation
• ↑ renal excretion

42. Hypercalcemia
• Calcium >15mg
• Results from:
– Hyperparathyroidism
– Hypothyroid states
– Renal disease
– Excessive intake of vitamin D
– Milk-alkali syndrome
– Certain drugs
– Malignant tumors – hypercalcemia of malignancy
• Tumor products promote bone breakdown
• Tumor growth in bone causing Ca++ release

43. Hypercalcemia
• Usually also see hypophosphatemia
• Effects:
– Many nonspecific – fatigue, weakness, lethargy
– Increases formation of kidney stones and pancreatic
stones
– Muscle cramps
– Bradycardia, cardiac arrest
– Pain
– GI activity also common
• Nausea, abdominal cramps
• Diarrhea / constipation
– Metastatic calcification

44. TREATMENT OF HYPERCALCEMIA
• Fluid replishment isotonic saline 2-4 l/day
• Diuretic frusemide 20-160mg i.v 8 hourly
• Oral/i.v inorganic phophate to inhibit true
resorption
• i.v sodium sulphate
• steroids

45. Hypocalcemia
• Calcium <8 mg.
• Hyperactive neuromuscular reflexes and tetany
differentiate it from hypercalcemia
• Convulsions in severe cases
• Caused by:
– Renal failure
– Lack of vitamin D
– Suppression of parathyroid function
– Hypersecretion of calcitonin
– Malabsorption states
– Abnormal intestinal acidity and acid/ base bal.
– Widespread infection or peritoneal inflammation

46. Hypocalcemia
• Diagnosis:
– Chvostek’s sign
– Trousseau’s sign
• Treatment
– IV calcium for acute
– Oral calcium and vitamin D for chronic

47. ACID-BASE BALANCE
– Blood - normal pH of 7.2 – 7.45
• < 7.2 = acidosis > 7.45 = alkalosis
• 3 buffer systems to maintain normal blood
pH
1. Buffers
2. Removal of CO2 by lungs
3. Removal of H+ ions by kidneys

49. FLUID THERAPY IN SURGICAL
PATIENTS
• PREOPERATIVE FLUID THERAPY
• INTRAOPERATIVE FLUID THERAPY
• POSTOPERATIVE FLUID THERAPY

50. PREOPERATIVE FLUID MANAGEMENT
CORRECTION OF HYPOVOLEMIA
• Why to correct?
• How to correct?
CORRECTION OF ANAEMIA
• To establish haemodynamic stability, proper tissue
oxygenation, cope with operative blood loss and for
adequate recovery & healing.
• Correct 48-72 hrs prior to restore 2,3-DPG levels in body.
CORRECTION OF OTHER FACTORS
• Fluid overload
• Hypokalemia
• Hyperkalemia

51. INTRAOPERATIVE FLUID
MANAGEMENT
• Choice of fluid: Crystalloid v/s Colloid
• RL most commonly used fluid. Others: NS and 5%D.
• Colloids more effective in restoring plasma volume as well
as correcting hypotension. FFP, Albumin, Dextran can be
used.
• Calculation: Correction of fluid deficit d/t starvation +
maintenance requirement for period of surgery + loss due
to tissue dissection/ hemorrhage.
• 2 mL/kg body weight – maintenance rate
• Role of Blood Transfusion
• Blood loss needs to be replaced with THREE times volume
of crystalloids

52. POST OPERATIVE FLUID
MANAGEMENT
• Aim: Maintain BP>100/70, P<120 and U/O of 30-50 ml/hour with normal
temp, warm skin, normal respiration & sensorium.
• Factors affecting post-operative fluid requirement
• First 24 hrs: 1.5L D5 + 500mL NS + 500 mL RL
• POD1: 2L D5 + 500mL NS + 500 mL RL
• POD2: Similar fluid + 40-60 mEq/L K+/day
• Post-op stress & pain causes ↑ secretion of ADH & Aldosterone hence salt
& water retained by kidney.
• Avoid K+ on 1st two days as renal status needs to be established; tissue
trauma already releases potassium; blood transfusion additionally may
add potassium; post-op metabolic acidosis shifts K extracellularly and
body stores of K generally suffice for the first 2 days.
• Infuse fluids over 24 hrs at steady rate.
• Spl considerations: Volume excess, hypoNa, hyperNa, post-op oliguria,
hypoK, hyperK.

53. REFERNCES
• V. Tripathi physiology
• Practical guidelines on Fluid Therapy
• Ganongs physiology

54. Thank you