5. Composition of Body Fluids:
Ca 2+
Mg 2+
K+
Na+
Cl-
PO4
3-
Organic
anion
HCO3
-
Protein
0
50
50
100
150
100
150
Cations Anions
ECFICF
Units : meq/l
6. PHYSICOCHEMICAL LAWS FOR FLUID
MOVEMENT
• DIFFUSION: movement of solute particles
along concentration gradient.
• OSMOSIS: movement of solvent across a
semipermeable membrane into regions of
higher solute concentration.
Osmolarity = solute/(solute+solvent)
(normal 280-310mosm/L)
7. OSMOLALITY: = solute/solvent (285-290mosm/kg)
Plasma osmolality= 2x(Na) + (Glucose/18) + (Urea/2.8)
•TONICITY: effective osmolality with respect to a semipermeable
membrane.
Plasma tonicity = 2 x (Na) + (Glucose/18)
Important in determining distribution of fluids across a cell
membrane and sensed by hypothalamic osmoreceptors.
•ONCOTIC PRESSURE
8. Regulation of Fluids:
Renal sympathetic nerves
Renin-angiotensin-
aldosterone system
Atrial natriuretic peptide (ANP)
9. COLLOIDS
• Fluids containing
molecules sufficiently large
enough to prevent transfer
across capillary
membranes.
• Solutions stay in the space
into which they are
infused.
• SEMISYNTHETIC COLLOID:
– GELATINS
– HYDROXYETHYL STARCHES
– DEXTRANS
• HUMAN PLASMA
DERIVATIVES
10. CRYSTALLOIDS
• Combination of water and
electrolytes
- Balanced salt solution:
electrolyte composition and
osmolality similar to
plasma; example: lactated
Ringer’s, Plasmlyte.
- Hypotonic salt solution:
electrolyte composition
lower than that of plasma;
example:D5W
- Hypertonic salt solution:
2.7% NaCl.
- Dextrose containing fluids
11.
12.
13.
14. PATHOPHYSIOLOGIC FLUID
ALTERATION IN PERIOPERATIVE
PHASE
• PREOPERATIVE:
– DIRECT INTRAVASCULAR DEPLETION
– LOSS FROM GI TRACT
– INFLAMMATION RELATED REDISTRIBUTION
– FLUID SEQUESTRATION IN THIRD SPACE LOSSES
• INTRAOPERATIVE:
– ALTERED DISTRIBUTION OF INTRAVASCULAR VOLUME.
– DIRECT LOSS OF INTRAVASCULAR VOLUME.
– INSENSIBLE LOSSES.
15. – INFLAMMATION RELATED REDISTRIBUTION.
– RENAL OUTPUT
• POSTOPERATIVE :
– INFLAMMATION AND IMMUNE RESPONSE (IL1,
TNF ALPHA, IL6, SIRS)
– CATABOLIC METABOLISM
– REGULATION OF SALT AND WATER BALANCE WITH
ADH RELEASE
16. PRACTICAL MANAGEMENT OF FLUID
THERAPY
• QUANTITY OF FLUID :
– TARGETTING OVERALL FLUID BALANCE
– GOAL DIRECTED THERAPY: based on
measurements as follows
• pulmonary arterial catheter,
• esophageal doppler monitoring and
• other targets like arterial waveform analysis, cvp,
lactate, echocardiography, oxygen extraction &venous
saturation or central venous saturation etc.
17. Clinical Evaluation of Fluid
Replacement
1. Urine Output: at least 1.0 ml/kg/hr
2. Vital Signs: BP and HR normal.
3. Physical Assessment: Skin and mucous membranes
no dry; no thirst in an awake patient.
. Laboratory tests: periodic monitoring of hemoglobin
and hematocrit.
18. Perioperative Fluid Requirements
The following factors must be taken into
account:
1- Maintenance fluid requirements
2- NPO and other deficits: NG suction, bowel
prep
3- Third space losses
4- Replacement of blood loss
5- Special additional losses: diarrhea
19. 1- Maintenance Fluid Requirements
• “4-2-1 Rule” HOLIDAY SEGAR FORMULA
- 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
- Extra fluid for fever, tracheotomy, denuded surfaces
20. 2- NPO and other deficits
• NPO deficit = number of hours NPO x
maintenance fluid requirement.
• Bowel prep may result in up to 1 L fluid loss.
• Measurable fluid losses, e.g. NG suctioning,
vomiting, ostomy output, biliary fistula and
tube.
21. 3- 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
• Superficial surgical trauma: 1-2 ml/kg/hr
• Minimal Surgical Trauma: 3-4 ml/kg/hr
- head and neck, hernia, knee surgery
• Moderate Surgical Trauma: 5-6 ml/kg/hr
- hysterectomy, chest surgery
• Severe surgical trauma: 8-10 ml/kg/hr (or more)
- Nehprectomy
22. Blood Loss
• Replace 3 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
23. SPECIAL CONSIDERATION
• PAEDIATRIC:
– Modification in preoperative fasting ( allowing
carbohydrate containing fluids upto 2 hours).
– Glucose free balanced crystalloid solutions to be used
intraoperatively.
– Avoid hypotonic fluids.
– Maintenance fluid using ½ to 2/3 of calculated 4-2-1
formula
– Return to oral fluids as soon as possible.
– Maintenance and ongoing losses to be replaced
seperately.
24. GERIATRIC:
• Decrease in total body water
• Decrease in GFR
• Decrease in urinary concentrating ability
• Increase in antidiuretic hormone (ADH)
• Increase in atrial natriuretic peptide (ANP)
• Decrease in aldosterone
• Decrease in thirst mechanism
• Decrease in free-water clearance
25. – The British Consensus Guidelines on Intravenous Fluid
Therapy for Adult Surgical Patients (GIFTASUP) for fluid
management recommends that “when crystalloid
resuscitation or replacement is indicated balanced salt
solution Ringer’s lactate/acetate or Hartmann’s solution
should replace 0.9% normal saline, except in cases of
hypochloremia for example from vomiting or gastric
drainage.”
– If colloids are indicated and used, lower-molecular-weight
colloids that can maintain adequate oncotic pressure should
be considered.
26. NEUROSURGERY PATIENTS :
Goals :
– maintaining baseline blood volume and cerebral
perfusion
– avoid significant decrease in serum sodium and
osmolality and oncotic pressure.
• Situations requiring specific management:
– Raised ICP- increasing serum osmolarity with
mannitol, hypertonic saline.
– Cerebral vasospasm – triple H( hypervolemia,
hemodilution, hypertension).
– Intacranial pathologic condition associated with
cerebral salt wasting, diabetes insipidus, SIADH.
27. • ORGAN FAILURE:
– HEART FAILURE: goals –
• Preserve cardiac output with limited preload.
• Minimise cardiac work . Avoid hypovolemia.
• Optimisation of electrolyte and fluid disturbances.
– Renal failure:
• Avoid both hypo- and hypervolemia.
• Dialysis day before surgery for euvolemia.
• Avoid large boluses of isotonic saline.
• Fluids available- potassium free HCO3- buffered dialysis
solution>potassium containing balanced crystalloids.
• Colloids- volume effect and potential toxicities
exaggerated.
28. – HEPATIC FAILURE
RELATIVE intravascular volume depletion with salt and water
retention.
– Careful assesement of volume status along with cardiac
output monitoring.
– Replace losses with isotonic crystalloids, colloids or blood.
– Avoid salt and water retention due to excessive volumes of
saline.
– Metabolism of lactates and other buffered solutions is
slowed.
– Hypertonic saline may be used in hepatic encephalopathy.
29. SEPSIS AND ACUTE LUNG INJURY
• INITIAL RESUSCITATION (<6 HRS) with targets-
– CVP8-12 mm hg
– MAP >65 mm hg
– u/o >0.5 ml/kg/hr
– Scvo2 >70% or mixed venous o2 saturation> 65%.
• Prefer crystalloids over colloids.
30. TRAUMA:
– APPROACH- permissive hypovolemia with fluids
targetted to achieve cerebration rather than
normotension.
– Early replacement with blood and blood products.
– After Clot stabilisation, now restore normal circulating
volume and tissue perfusion.
31. • BURNS :
– I.V. FLUIDSinstituted for burns >15% BSA(adults), >10%
BSA( children)
– Prefer crystalloids over colloids.
– Based on PARKLAND FORMULA:
• 1ST 8hrs- 2ml/kg * % TBSA( RL )
• Next 16hrs - 2ml/kg * % TBSA( RL)
• Next 24 hrs – 0.8ml/kg %TBSA (5%DEXTROSE) +
0.015ML/KG *%TBSA ( 5% ALBUMIN)
32. OBSTETRICS; PREECLAMPSIA
• Reduced plasma volume in contrast to volume
expansion as in normal pregnancy.
• Hypoalbuminemia and endothelial dysfunction.
• Management
– Restricted volume of crystalloid including drug
diluents.
– Blood loss in peripartum or perioperative period to be
replaced with appropriate volumes of blood, colloids
& crystalloids.
– Invasive monitoring required.
– Oliguria in presence of normal renal function not to
be treated with fluid boluses.
33. UPPER GI LOSS
• Fluid and electrolyte abnormalities:
dehydration, hypochloremic metabolic
alkalosis with paradoxically acid urine and
hypocalcaemia.
• Correction: gradual rehydration with normal
saline and potassium supplementation.
• Surgery to treat gastric outlet obstruction to
be scheduled after correction of acid base
status.
34. References
• Miller’s anesthesia 8th edition. MARK R.
EDWARDS, MICHEAL P. W. GROCOTT
• Lippincott’s ANESTHESIA REVIEW2015; PAUL
SIKKA .
• British Consensus Guidelines on Intravenous Fluid
Therapy for Adult Surgical Patients GIFTASUP
2011 REVISED
• SITES http://ceaccp.oxfordjournals.org/content
• http://www.ncbi.nlm.nih.gov/pubmed/19302633
35. 1. All of the following are signs of dehydration
except:
A. Progressive metabolic acidosis.
B. Urinary specific gravity >1.010
C. Urine osmolality <300mOsm/kg
D. Urine sodium <10 meq/l
36. C. When dehydrated, patients with normal
renal function will retain sodium and produce
a concentrated urine. Urine osmolality is
typically greater than 450 mOsm/kg in this
setting. Urine sodium will be low, and specific
gravity will be high.
37. 2. Regarding central venous pressure monitoring:
A. Low values of <5mm hg may be considered
normal in the absence of other signs of
hypovolemia.
B. CVP readings can be interpretated
independently of clinical setting.
C. CVP monitoring is never indicated in patients
with normal cardiac & pulmonary function.
D. In a patient with right ventricular dysfunction, a
CVP of 10 mm hg should be considered
elevated.
38. • A. CVP measurements must be evaluated in
context of the clinical setting. Factors such as
underlying cardiopulmonary disease, patient
position, and anatomy can affect the values. A
CVP of <5 mm Hg can be normal in a healthy
patient without signs of hypovolemia. For surgical
cases during which large fluid shifts are expected,
placement of a CVP monitor may be indicated.
Patients with compromised right ventricular
function generally have high CVPs, and thus, a
CVP of 10 mm Hg should be considered normal to
low depending on the degree of dysfunction.
39. 3. In healthy patients, the lactate in lactated
ringer solution:
1. Causes lactic acidosis.
2. Is converted to bicarbonate by the liver.
3. Is rapidly bound by albumin.
4. Causes a hyperchloremic metabolic acidosis.
40. B. In healthy patients the lactate in lactated
Ringers solution is rapidly converted to
bicarbonate by the liver and does not cause a
lactic acidosis. Administration of a large
volume of normal saline can cause a
hyperchloremic metabolic acidosis. Lactate is
not bound by albumin.
41. 4. All of the following fluids are generally
considered to be isotonic except:
1. Lactated ringer solution
2. Normal saline
3. D5 normal saline
4. D5+1/4normal saline
42. • C. An intravenous solution’s effect on fluid movement
depends in part on its tonicity. This term is sometimes
used interchangeably with osmolarity, although they
are subtly different. Osmolarity is the number of
osmoles or moles of solute per liter of solution.
Tonicity is the effective osmolality and is equal to the
sum of the concentrations of the solutes which have
the capacity to exert an osmotic force across the
membrane. A solution is isotonic if its tonicity falls
within (or near) the normal range for blood serum—
from 275 to 295 mOsm/kg. A hypotonic solution has
lower osmolarity (<250), and a hypertonic solution has
higher osmolarity (>350).
43. 5. All of the following statements regarding
dextran solution are true except:
A. Dextran 40 may improve blood flow through
microcirculation.
B. Dextrans may have antiplatelet effect.
C. Large volume infusion of dextrans have been
associated with renal failure.
D. Dextran 40 is better volume expander.
44. D. While dextran 40 has a molecular weight
of 40,000, dextran 70 has a molecular weight
of 70,000, and therefore, the latter is broken
down more slowly, lasts longer, and is a better
volume expander. Dextran 40 appears to
improve blood flow through the
microcirculation, and all dextrans may have
antiplatelet effects. Infusion of large volume
of dextran (>20 mL/kg/day) has been
associated with renal failure.
45. 6. Which of the following statement is true regarding fluid
loss:
A. Substantial evaporative losses can be associated with
large wounds & are directly proportionated with
surface area exposed.
B. Internal redistribution of fluids ,”third spacing” cannot
cause massive fluid shifts.
C. Traumatised inflammed or infected tissues can only
sequester minimal amount of fluid in interstitial space
D. Cellular dysfunction as a result of hypoxia usually
produces a decrease in intracellular fluid volume
46. A. Substantial evaporative losses can be
associated with large wounds and are directly
proportionate to the surface area exposed.
Third spacing can cause massive fluid shifts,
and traumatized, inflamed, or infected tissue
can sequester large amounts of fluid. Cellular
dysfunction as a result of hypoxia usually
produces an increase in intracellular
fluid volume.
47. 7. All of the following are advantages of
crystalloid solution except:
A. Nontoxic
B. Reaction free
C. Relatively inexpensive
D. Ability to remain in intravascular space
48. D. Advantages of crystalloid solutions are that they
are nontoxic, reaction-free, and inexpensive.
Colloid solutions are composed of large-
molecular-weight substances that remain in the
intravascular space longer than crystalloids, and
typically, the initial volume of distribution is
equivalent to the plasma volume. The synthetic
colloids and processed albumin have minimal or
no risks of infection. Colloids are more expensive
than crystalloids, but have fewer risks than blood
products.
49. 8. Administration of large volumes of saline can
lead to:
A. Metabolic acidosis
B. Hyperchloremic induced nongap metabolic
acidosis
C. Anion gap metabolic lactic acidosis
D. None of the above.
50. B.Normal saline (0.9% NaCl) is slightly
hypertonic and contains more chloride than
extracellular fluid. Administration of large
volumes of normal saline solution can lead to
a hyperchloremic non–anion gap metabolic
acidosis. Administration of large amounts of
lactated Ringer solution may result in a
metabolic alkalosis because of increased
bicarbonate production from the metabolism
of lactate.
51. 9. All of the following contains potassium
except:
A. Lactated ringer solution
B. Plasmalyte
C. Hespan
D. Packed RBCs
52. C. Hespan is colloid containing starch and saline.
All of the other options contain potassium.
Many patients with hyperkalemia, including
patients with renal failure, routinely receive
normal saline because it contains no
potassium.
53. 10. All are true for normal saline except :
A. Osmolarity higher than plasma.
B. Osmolality similar to plasma.
C. Isotonic to plasma.
D. Slightly alkaline.
54. 11. Maximum tolerated amount of blood loss
without any hemodynamic alteration:
A. 20%
B. 25%
C. 30%
D. 35%
55. 12. Parkland fluid resuscitation is for:
A. Burns
B. Trauma
C. Sepsis
D. Organ failure
56. 13. Triple H therapy for cerebral vasospasm after
subarachnoid hemorrhage include:
A. Hypoxia , Hypervolemia, hemodilution
B. Hypervolemia, hemodilution, hypertension.
C. Hypocarbia, hemodilution, hypertension.
D. Hypervolemia, hypercarbia, hypotension.
57. 14. Upper GI losses to be replaced with:
A. Lactated ringer solution.
B. Normal saline.
C. Normal saline with K+ supplementation.
D. D5+ ½ NS
58. Dehydration occurs as a result of water loss, reduced total body
Cl−content, and alkalosis
caused by proton loss, with raised serum HCO3.The
initial renal response is formation of urine with low Cl−
and high HCO3− content. However, progressive dehydration
leads to increased aldosterone secretion, aimed at
retaining Na+ and water. Na+ is retained at the expense
of K+ and H+ ions, leading to hypokalemia, and worsening
metabolic alkalosis with a paradoxically acid urine.
The alkalosis also reduces the circulating ionized fraction
of Ca2+.
59. 15.Maintenance requirements in postoperative
period include all except:
A. 1500-2500 ml in 24 hrs or 1 to 1.2 ml/kg/hr
B. 50–100 meq sodium
C. 40-80 meq potassium
D. 60 meq calcium
60. 16. The following ion concentrations are
corrects:
A. 0.9% saline= sodium 131 mmol/L
B. Albumin 4.5% =calcium 2mmol/L
C. Hartmann’s solution = 154 mmol/L
D. gelofuscine = calcium 5.1 mmol/L
E. Dextrose 4% Saline 0.18% = sodium 30
mmol/L
61. 17. Concerning the use of hydroxylethyl starch as an
intravenous fluid:
A. Glomerular filteration is the major route of
elimination
B. About 48% of the total dose is deposited in the
reticuloendothelial system.
C. Large volumes may alter coagulation by lowering
factor X concentration.
D. Incidence of allergic reactions is similar to that of the
gelatins
E. Serum amylase concentrations may be elevated .
62. 18. Perioperative fluids:
A. Should not be given orally within 4 hrs of anaesthesia.
B. Need to replace unmeasured losses of up to 5
mlkg−1 hr−1 during abdominal surgery.
C. Are a frequent cause of left ventricular failure and
pulmonary oedema.
D. Should be restricted in the first 24 hrs post-op due to
inappropriate ADH secretion.
E. Should be included in day of surgery fluid balance.
63. 19. What regulates water homeostasis
A. Thirst
B. Arginine vasopressin
C. Kidneys
D. All of the above
64. 19. What regulates water homeostasis:
A. Thirst [ Fluid homeostasis depends on proper water intake
(regulated by thirst mechanism) and on urinary excretion of
free water (regulated by AVP).]
B. Arginine vasopressin
C. Kidneys
D. All of the above [ The serum sodium concentration and thus
serum osmolality are controlled by water homeostasis.
Water homeostasis is mediated by thirst, arginine
vasopressin, and the kidneys. Abnormal water balance
manifests as an abnormality in the serum sodium
concentration (hypernatremia or hyponatremia).
65. 20. ECF volume contraction results in
A. Hypotension
B. Stimulation of baroreceptors
C. Stimulation of sympathetic nervous system
D. Stimulation of renin secretion
E. All of the above.
66. ECF volume contraction results in
A. Hypotension [ Clinically ECF volume contraction manifest as a
decreased plasma volume and hypotension. Hypotension is due to
decreased venous return (preload) and diminished cardiac
output.]
B. Stimulation of baroreceptors [ Hypotension stimulates barorecept
ors inthe carotid sinus and aortic arch.].
C. Stimulation of sympathetic nervous system[ Hypotension activates
the sympathetic nervous system and the renin-angiotensin
system.]
D. Stimulation of renin secretion
E. All of the above T [ The net effect is to maintain mean arterial
pressure and cerebral and coronary perfusion. In contrast to this
cardiovascular response, the renal response attempts to restore
the ECF volume.