intraoperative management in anesthesia and surgery. Adequate fluid administration ensures maintenance of intravascular volume, tissue perfusion, and organ oxygen delivery, while avoiding the morbidity associated with both hypovolemia and fluid overload. Perioperative fluid balance is influenced by anesthetic technique, surgical trauma, patient comorbidities, and the dynamic changes in vascular permeability and redistribution of body water. Thus, fluid therapy must be individualized rather than formulaic. --- Historical Background Earlier, fluid replacement was based on the “4-2-1 rule” and the “third-space loss” concept. Recent evidence, however, has shifted practice towards restrictive or goal-directed therapy. Advances in monitoring (pulse contour analysis, esophageal Doppler, dynamic preload indices) have refined how intraoperative fluids are guided. --- Physiology of Fluid Balance The human body contains approximately 60% of body weight as water. Intracellular fluid (ICF): 2/3 of total body water. Extracellular fluid (ECF): 1/3, of which plasma is 1/4 and interstitial fluid is 3/4. Fluid movement between compartments depends on Starling forces: Hydrostatic pressure. Oncotic pressure (albumin major contributor). Capillary permeability.

1. Perioperative Fluid
Therapy
Dr.Indubala Maurya MD,DNB
Assistant Professor
Dept of Aanesthesia & Critical Care
MGMCRI

2. TOTAL BODY WATER
 Approx. 60% Body weight
 Varies with age, gender and body habitus
 50% BW in females
 80% BW in infants
 Less in obese : fat contain little water

3. Body Water Compartments
 Intracellular volume : 2/3 of TBW
 Extracellular volume : 1/3 of TBW
- Intravascular : Plasma volume (1/4)
- Extravascular: Interstitial fluid and others(3/4)

4. Preoperative Evaluation of Fluid Status
- Mental status
- H/O intake and output
- Blood pressure: supine and standing
- Heart rate
- Skin turgor
- Urinary output
- CVP

5. Orthostatic Hypotension
• Systolic blood pressure decrease of greater than 20mmHg
from supine to standing
• Indicates fluid deficit of 6-8% body weight
- Heart rate should increase as a compensatory measure
- If no increase in heart rate, may indicate autonomic
dysfunction or antihypertensive drug therapy

6.  Osmoles :unit for conc. Of osmotically active particles
 Osmolality: osmotic active solute per volume of solution
( mOsm/L)
 Osmolarity : mOsm/Kg
 Plasma osmolarity : 290 mOsm/kg
 Tonicity ( relative osmotic activity )
 Isotonic/ hypotonic/hypertonic
BASICS

7. Intravenous Fluids Therapy
Intravenous fluid therapy may consist of
Intravenous fluid therapy may consist of infusions of
infusions of
crystalloids, colloids, or a combination of both.
crystalloids, colloids, or a combination of both.
Indications
Indications
 Volume resuscitation
Volume resuscitation
 Vehicle for i/v drugs
Vehicle for i/v drugs
 KVO
KVO

8. Types
• Crystalloids
• Colloids

9. Crystalloids
 Clear fluids made up of water and electrolyte solutions; Will
cross a semi-permeable membrane
 Grouped as isotonic, hypertonic, and hypotonic
 Eg:
 Normal saline 0.9%,3 %
 Dextrose solutions 5 %,10%,20%,25%
 DNS
 Ringer’s lactate
 Isolyte P

10. Crystalloids
0.9% Normal Saline
 Contains: Na+ 154 mmol/l, Cl-
- 154 mmol/l
 Osm : 308mosm/l, pH 6.0
 IsoOsmolar compared to normal plasma.
 Indication :
 Intravascular resuscitation and replacement of salt loss
e.g. diarrhoea and vomiting.
 Also for diluting packed RBCs prior to transfusion
 Used for diluting Drugs

11.  Distribution:
 Stays almost entirely in the extracellular space.
Of 1 litre - 750ml extra vascular fluid; 250ml intravascular fluid.
 100ml blood loss – need to give 400ml N. saline [only 25% remains
intravascular
 Complications:
 When given in large volume can produces Hyperchloremic
metabolic acidosis because of high Na+ and Cl- content.

12. 0.45% Normal saline = ‘Half’ Normal Saline
= HYPOtonic saline
 Na+ 77mmol/l, Cl- 77mmol/l,
 Osmo 154mOsm/l
 Indications :
 Fluid therapy for paediatric pt
 Maintenance fluid therapy
 Complications :
 Leads to HYPOnatraemia if plasma sodium is normal
 May cause rapid reduction in serum sodium if used in excess or
infused too rapidly. This may lead to cerebral oedema and rarely,
central pontine demyelinosis ; Use with caution!

13. 3.0 % Saline = HYPERtonic
saline
 3% contain 513 mmol/l of Na+ and Cl- each,
 osmol of 1026 mOsm/l; pH 5.0
 Indications :
 Treatment of severe symptomatic hyponatremia
(coma, seizure)
 To resuscitate hypovolemic shock

14.  Leads to an osmotic gradient between the ECF and
ICF, causing passage of fluid into the EC space.
 Must be administered slowly and preferably with
CV line because it carries risk of causing phlebitis,
necrosis, hemolysis.
 Complications :
 Precaution in pt. with CHF
 severe renal insufficiency, edema with sod. retention.

15. Dextrose
5% Dextrose (often written D5W)
 50g/l of glucose, 252mOsm/l, pH 4.5
 Regarded as ‘electrolyte free’ – contains NO Sodium, Potassium,
Chloride or Calcium
 Indication :
 Primarily used to maintain water balance in patients who are not able to
take anything by mouth;
 Commonly used post-operatively in conjunction with salt retaining fluids
ie saline
 Hypernatremia treatment

16.  When infused is rapidly redistributed into the
intracellular space; Less than 10% stays in the
intravascular space therefore it is of limited
use in fluid resuscitation.
 Side effects:
 Iatrogenic hyponatraemia in surgical patient
 Hyperglycemia
 Not compatible with blood ,cause hemolysis
conc 5% 10% 20% 25% plasma
Osmolarity 252 505 1010 1262 290

17. Ringer Lactate
 Most physiological solution
 Electrolyte composition similar to ECF
 One litre of lactated Ringer's solution contains:
 Sodium ion= 130 mmol/L.
 Chloride ion = 109 mmol/L.
 Lactate = 28 mmol/L.
 Potassium ion = 4 mmol/L.
 Calcium ion = 1.5 mmol/L
 Osmolarity of 273 , pH of 6.5

18.  Lactate is converted to bicarbonate in liver
 Indications :
 Deficit ,Intraoperative fluid loss
 Severe hypovolemia
 Precautions:
 Severe metabolic acidosis ( impaired lactate conversion)
 Don’t give with blood product ( Ca bind with citrate 
reduced anticoagulant activity )

19. DNS
 0.9% saline & 5% dextrose
 Na+ 154, Cl- 154, 5 gm. Glucose
 Osm : 432 mosm/L
 Indication :
 Maintenance solution
 Correction of fluid deficit with supply
of energy
 Compatible with blood

20. IsoLyte -P
Multiple electrolyte & dextrose solution
Na+ : 26
K+ : 20
Mg++ : 03
Cl- : 21
Acetate : 23
Ph+ : 03
Isotonic
Indication :Pediatric maintenance fluid

21. Colloids
 The colloid solutions contain particles which do not readily
cross semi-permeable membranes such as the capillary
membrane.
 Thus the volume infused stays (initially) almost entirely within
the intravascular space .
 Stay intravascular for a prolonged period compared to
crystalloids.
 However they leak out of the intravascular space when the
capillary permeability significantly changes e.g. Severe trauma
or sepsis.

22.  Because of their gelatinous properties they cause
platelet dysfunction and interfere with fibrinolysis
and coagulation factors (factor VIII) – thus they can
cause significant coagulopathy in large volumes.
 Natural : Albumin
 Artificial : Gelatin and Dextran , HES

23. ALBUMIN
 Principal natural colloid comprising of 50-60% of all plasma
proteins.
 Synthesized only in liver and has a half life of app. 20 days.
 5% soln is iso oncotic and leads to 80% initial vol expansion
25% soln leads to 200-400% increase in vol.
 Used
 For emergency treatment of shock especially due to loss of plasma,
 acute management of burns
 fluid resuscitation in ICU
 Hypoalbumineamia.

24.  Side effects :
 pruritis, anaphylactoid reactions and coagulation
abnormalities as compared to synthetic colloids.
 Disadvantages
 cost effectiveness
 volume overload (in septic shock pt albumin add to
interstitial edema)

25. DEXTRAN
 Highly branched polysaccharide molecules
 Produced by synthesis using the bacterial enzyme dextran
sucrase from the bacterium Leuconostoc mesenteroids.
 Most widely used are 6%(dextran 70) and 10%(dextran 40)
soln.
 Excreted via kidney primarily.
 Both lead to a higher vol expansion as compared to HES and
5% albumin.

26.  Used mainly to improve microcirculatory flow in
microsurgical re-implantation .
 Also used in extracorporeal circulation during cardiopulmnary
bypass.
 Side effects: Anaphylactic reactions, Coagulation abn,
Interference with cross match, Ppt of ARF.

27. GELATINS
 Large mol. wt. proteins formed from
hydrolysis of collagen.
 Produced by thermal degradation of cattle-
bone gelatin.
 3 types of gelatin soln currently in use are;
1. Succynylated or modified fluid
gelatin(e.g. Gelofusine, Plasmagel)
2. Urea crosslinked gelatins(e.g. Polygeline)
3. Oxypolygelatins(e.g. Gelifundol)

28.  Gelatins lead to 70-80% of vol expansion
 Indication :
 Rapid expansion of intravascular volume and correction of
hypotension
 Advantage :
 cost effectiveness and no effect of renal impairment ,does not
affect coagulation
 Disadvantage :
 Hypersenstivity
 Anaphylactoid reactions

29. HYDROXYETHYL
STARCHES
 Derivatives of amylopectin, which is a highly
branched compound of starch.
 6% HES soln are isooncotic
 10% soln are hyper oncotic , with a vol effect
exceeding the infused vol .(about 145%)
 Duration of vol expansion is usually 8-12 H.

30.  Advantage
 Cost effective: cheaper and comparable vol of expansion to albumin.
 Disadvantage: assoc. with 1st
& 2nd
generation HES
- Coagulation abn
- Accumulation
- Anaphylactoid reactions
- Renal impairment
- Increase in amylase level

31. TETRASTARCH:3RD
GEN. HES
 Newer starch based plasma expander
 Improved safety and pharmacological prop
 Minimal effect on coagulation process and platelet
function
 Less accumulation and tissue storage
 No effects on renal function
 Positive effects on tissue oxygenation and
microcirculation

32. Colloid or Crystalloid Resuscitation
Recommendations:
 Colloid should NOT be used as the sole fluid replacement in
resuscitation ,volumes infused should be limited because of
side effects and lack of evidence for their continued use in the
acutely ill.
 In severely ill patients – principally use crystalloid and
blood products; Colloid may be used in limited volume to
reduce volume of fluids required or until blood products are
available.

33.  In elective surgical patients
 Replace fluid loss with ‘physiological Ringer’s solutions.
 Blood products and colloid may be needed to replace
intravascular volume acutely.

34. Peri- operative Fluid Requirements
• The following factors must be taken into account:
• C V E
• Maintenance fluid
• Deficit
• Third space losses
• Replacement of loss

35. COMPENSATORY INTRAVASCULAR VOLUME
EXPANSION
 Most gen and regional anaesthetics cause arteriolar and
venous dilatation, expanding the vascular capacity, which
reduces the peripheral venous pressure, venous return, and
cardiac output.
 Fluid must be adm. to expand the blood vol to compensate for
venodilation .
 Expansion with 5-7ml/kg of BSS must occur before or
simultaneous with the onset of anaesthesia .

36. Maintenance Fluid Requirements
• “4-2-1 Rule”
- 4 ml/kg/hr for the first 10 kg of body weight
- 2 ml/kg/hr for the second 10 kg body weight
- 1 ml/kg/hr subsequent kg body weight
Eg : 70 Kg pt
Maintenance fluid : 40+20+50= 110 ml/hr

37. Deficit
• Deficit = number of hours NPO x maintenance fluid requirement.
• Measurable fluid losses, e.g. NG suctioning, vomiting, stoma
output.
 70 kg pt fasting for 8 hrs
 Deficit : 8 X 110 = 880 ml
 Half in first hr
 One fourth each in next two hr .

38. 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.

39. Replacing Third Space Losses
Minimal Surgical Trauma: 0-2 ml/kg/hr
- e.g. herniorrhaphy
Moderate Surgical Trauma: 2-4 ml/kg/hr
- e.g. cholecystectomy
Severe surgical trauma: 4-6 ml/kg/hr (or even more)
- e.g. major bowel resection

40. Blood Loss
• Replace 4 cc of crystalloid solution per cc of blood loss
(crystalloid solutions leave the intravascular space)
• When using blood products or colloids replace blood loss
volume per volume.

41. Fluid management, starting with a hemoglobin level of
15 g/dL, for a 70-kg patient undergoing gastrectomy
who has been fasting for 8 hours.
 Maintenance rate is 110 mL/hr,
Deficit of 880 mL
First hr = CVE+ Half of deficit + maintenance + loss+ third space loss
 350+440+110+50 + 420
 Second hr = one fourth of deficit + maintenance + loss+ third space loss
 220+ 110+ 250 + 420
 Third hr = one fourth of deficit + maintenance + loss+ third space loss
 220+ 110+ 250 + 420
Fourth hr = Maintenance + loss+ third space loss
 110+ 50 + 420

42. Summary
 Most physiological :RL
 Rich in sodium : NS,DNS
 Rich in potassium :ISo –p
 Glucose free: RL,NS,3% saline
 Sodium free: Dextrose
 Potassium free: NS,DNS,Dextrose
 Can correct acidosis directly : RL,ISo-p

43. Thank you