2. Water physiology
Water is the most plentiful constituent of the
human body
approximately 75% of birthweight for a term
infant
decreases to approximately 60% of body
weight during the 1st yr of life and basically
remains at this level until puberty
3. Fluid Compartments
TBW is divided between 2 main compartments
intracellular fluid (ICF)
extracellular fluid (ECF)
ECF
Plasma
Interstitial fluid
Transcellular fluid
4. Fluid compartments & volumes
changes with age
Compo
nents
Premat
ure
Neonat
e
Infant Adult
ECF 50 35 30 20
ICF 30 40 40 40
Plasma 5 5 5 5
Total 85 80 75 65
6. Continu….
Plasma water is 5% of body weight
Blood volume is usually 8% of body weight
The volume of plasma water can be altered by
pathologic conditions
dehydration, anemia, polycythemia, heart failure,
abnormal plasma osmolality and hypoalbuminemia
7. Continu…
Interstitial fluid - normally 15% of body
weight
can increase dramatically in diseases
associated with edema
heart failure, protein-losing enteropathy, liver
failure, nephrotic syndrome, and sepsis
10. Electrolyte Composition in
Body Fluids (Normal)
Electroly
te
Plasma Exracellu
lar
Intra
cellular
Na+ 142 145 10
K+ 4 4 159
Mg2+ 2 2 40
Ca2+ 5 3 1
Cl- 103 117 10
HCO3
- 25 27 7
11. Daily Loss of Water
Source of Loss
Normal
Activity and
Temperature
(mL)
Normal
Activity High
Temperature
(mL)
Prolonged
Exercise (mL)
Urine 1400 1200 500
Sweat 100 1400 5000
Feces 100 100 100
Insensible
losses
700 600 1000
Total 2300 3300 6600
12. Determining fluid
requirement
Howland ----1911----energy consumption in
children
In 1957 holliday and segar correlated
calorie requirement with basal metabolism
and active energy needs
13. Calorie requirement is
0-10kg=100kcal/kg/day
10-20kg=50kcal/kg/day+1000kcal
>20kg=1500kcal+20cal/kg
Mb of 1cal produces 0.2ml of water and
consumes 1.2ml
On transporting this in to hourly basis
15. Clinical assessment of
dehydartion
Symptoms&sign
s
Mild Mode Severe
Wt loss <5 5-10 >10
General condition Alert/restless Thirsty/lethrgic Cold/thirsty
Pulse Normal rate
/voume
Rapid/weak Rapid/feeble
Respiration Normal Rapid Rapid/deep
Systolic pressure N N/Low Unrecordable
Anterior fonta N/sunken Sunken Very sunken
Eyes n/sunken Sunken/dry Grossly sunken
Skin N Decreased Markedly
decresed
Mucous
membrane
Moist Dry Very dry
Urine output Adequate Less ,dark
coloured
Oliguria/anuria
Capillary filling Normal <2sec >3sec
Estimated deficit 30-50ml/kg 60-90ml/kg 100ml
16. Investigation for confirming
dehydration
Serum osmolarity /serum sodium
Acid base status,serum ph and base deficit
Serum potassium compared with ph
Urine output
17. Correction of flui deficit
Done in three phases
Emergency phase20-30ml/kg over 10-
20min (intital resucitation with isotonic saline
Repletion phase 125-50ml/kg over 6-8hr(or
half the deficit)
Repletion phase 2remainder of the deficit
18. Mild dehydration
Correction is with ORS
Package containing
Glucose 20gm/Lwater
Nacl 3.5gm/Lwater
Kcl4.5gm/Lwater
Trisodium citrate 2.9gm/Lwater
Sodium bocarbonate2.5gm/L water
22. Fluid required to compensate
for fasting
The younger child with higher basl
metabolism
Prolonged fsting which occurred inadverently
or out of necesssity
In the hot summer m0nth
A febrile child
In polycythemia when there is a risk of
dehydration predisposing to thrombosis
23. Monitoring fluid loss an
replacement
Routine monitoring pulse
oxy,nibp,ecg,precordial stethescope 15-20%
Urine out put
26. heamatocrit
A normal hct means ,a hct within two
standard deviation for the age
An acceptable hct is with which an infant or
child can tolerate with out blood transfusion
27. Blood
The use of blood products in pediatric surgical
patients has diminished greatly because of the
fear of transmission of disease—particularly
human immunodeficiency virus (HIV). Because
HIV, hepatitis B virus (HBV), hepatitis C virus
(HCV), and a number of other disease-causing
viruses can be transmitted with as little as
10 mL of packed red blood cells (PRBCs),
administration of any blood product requires
clear, medically defensible clinical indications
that are preferably recorded on the anesthetic
record
28. Blood loss and replacement
In general, blood volume is approximately
100 to 120 mL/kg for a preterm infant,
90 mL/kg for a full-term infant, 80 mL/kg
for a child 3 to 12 months old, and 70 mL/kg
for a child older than 1 year.These are
merely estimates of blood volume.The
individual child's blood volume is calculated
by simple proportion by multiplying the
child's weight by the estimated blood
volume (EBV) per kilogram
29. Maximum allowable blood loss
MABL=EBV*(Starting hct-target hct)/strting
hct
Volume to be transfused=(desired hct-
presenthct)8ebv/hct of prbc
30. Normal and acceptable hct
value
Premature 40-45 35
Newborn 45-65 30-35
3months 30-42 25
31. Composition of IV fluids (per 1000 ml)
Fluid Na K Cl Glucose Others
5%
dextrose
- - - 50 g -
10%
dextrose
- - - 100 g -
Normal
saline
154 mEq - 154 mEq - -
N/2 saline 77 mEq - 77 mEq - -
N/5 saline
in 5%
dextrose
30 mEq - 30 mEq 40 g -
3% saline 513 mEq - 513 mEq - -
Ringer’s
lactate
130 mEq 4 mEq 109 mEq - Lactate 29
Isolyte P 26 mEq 19 mEq 22 mEq 50 g acetate 24,
PO4 3, Mg
3
32. Some other fluids meq/L
Fluid Na K Cl Glucose Others
Plasmalyte
A
140 5 98 Mg3
acetate 27
Albumin
5%
145+15 <2.5 100
Hexa
starch 6%
154 154
33. Conclusion
Fluid therapy should be tailored to the needs
of individual patient
Basal fluid and energy requirements as well
as correction of derangements may be met
by crystalloids
Infusion of large volume of crystalloid to
correct intravascular deficit may produce
tissue oedema,coagulation abnormality and
organ dysfunction