Perioperative Fluid Management

In Pediatric Patient

Arie Utariani

Department of Anesthesiology & Reanimation

Faculty of Medicine, Airlangga University

Surabaya

Physiology

- Percentage of body water exceeds that of adult.

- Expanded extracellular space which contracts during

first week of life :

1. Increasing glomerular filtration rate

2. Physiologic diuresis occurs with loss of about 10%

of total body weight

3. Some SGA / dysmature infants may not have

expanded extracelllar space

- By 6 months of age, healthy infants have kidney function

that is almost normal.

Body weight, body surface and body fluid in children and adults

Weight (kg)

Surface area(m2)

S/W Total water (%)

ECF (%)

ICF (%)

Premature

Neonate

1.5

0.15

0.1 80

50

30

Newborn

3

0.2

0.07 78

45

35

1 year

10

0.5

0.05 65

25

40

3 year

15

0.6

0.04 60

20

40

9 years

30

1

0.03 60

20

40

Adult

70

1.7

0.02 60

20

40

Hochman et.al. Reproduced

Premature/Newborn

80 – 70 % TBW

ICF

30-35%

ISF

40-37.5%

IVF

10-7.5%

Child

65 – 60 % TBW

ICF

40%

ISF

18-15%

IVF

7-5%

Fluid distribution

Composition of Body Fluid

1500g 2500g 3500g Adult

Water

Blood

Solids Fat

Comparison of body composition of infants & adults

Composition of Body Fluid

Composition of Body Fluid

Intracellular fluid

Extracellular fluid

Lactated ringer solution

0.45 NaCL

0.9% NaCL 3% NaCL

Na+

10

142

130 77

154

590

K-

150

4

4

Ca++

-

5

3

NH4+

-

0.3

CL-

-

103

109 77

154

590

HCO3-

-

27

28

HPO4-

10

3

-

Cations (mEq/L) Amions (mEq/L)

Source: Herrin J, Fluid & electrolytes, 1997

Mg++

40

3

Composition of Body Fluid

Source

Gastric

Pancreas Bile

Illeostomy

Diarrhea

Sweat

Blood Urine

Na+

50

140 130

130

50

50

140 0-100

K+(mEq/L)

10-15

5 5

15-20

35

5

4-5 20-100

CI-(mEq/L)

150

50-100 100

120

40

55

100 70-100

HCO3-

0

100 40

25-30

50

0

25 0

pH

1

9 8

8

Alkaline

7.4 4.5-8.5

Osmolality

(mOsm/L)

300

300 300

300

285-295 50-1400

Source: Herrin J, Fluid & electrolytes, 1997

Cause of Loss

Output

Urine

Insensible loss

Skin

Respiratory tract

“Hidden intake” (from

burning 100 calories)

Total

Volume of Loss

(mL/100 kcal)

70

30

15

15

100

Normal water losses in infants & children

Perioperative fluid management

I. Maintenance

II. Deficit

III. Replacement

How should be given ?

What kind of fluid ?

How much ?

I. MAINTENANCE

1. Maintenance fluid and caloric requirements of neonate /

newborn

Age

Day 1

Day 2

Day 3

Day 4

Day 5

Vol (mL/kg/day)

50 – 80

80 – 100

100 – 120

120 – 150

150

Energy (KCal/kg/day)

40 – 50

50 – 70

70 -90

90 – 110

110 – 120

Weight (kg)

<10

10-20

>20

Day

100mL/kg

1000mL + 50 mL/kg

1500 ml + 20 mL/kg

Hour

4mL/kg

40mL + 2 mL/kg

60 mL + 1 mL/kg

Maintenance fluid requirements

2. Hourly and Daily Maintenance Fluid Requirements

of Children

For example :

a 25 kg child would required

1000 ml + 500 ml + 100 ml = 1600 ml

3. Fluid requirements to be based on BSA

1500ml / m2 BSA / day

For example :

3 kg infant : 1500 ml x 0.2 x day = 300 ml/day

Source: Holiday MA, Segar WE; The maintenance need

for water in parenteral fluid therapy padiatrics

Choice of the maintenance fluid

• Crystalloid :

Depent on the glucose and electrolyte needs

Hypotonic : D 10% 0.18 NS

D 5% 0.225 NS

D 5% 0.45 NS

• Neonate & premature or small for gestation age are at risk

for perioperative of hypoglycaemia.

• Monitoring of blood glucose concentration is recommended

II. DEFICIT

Preoperative fluid deficits :

Maintenance + fluid deficit

1. Fasting period

2. Hydration

3. Electrolyte imbalance

Solids

4

6

8

Age

< 6 months

6-36 months

> 36 months

Clear liquids

2

3

3

Fasting time (Hours)

1. Fasting period

Fasting (NPO) guidelines for children and adults

Replacement of fasting

Hourly fluid requirement x length of fasting (hours)

For example : a 5 kg child

5 kg x 4ml/kg/h x 4 h = 80 ml

Given : 50% in the first hour

25% in the second and third hour

Choice of fasting fluid : Crystalloid fluid

- Hypotonic solution

- Isotonic solution

Clinical findings

% body weight loss

Estimation fluid defisit

Pulse

Blood pressure

Respiration

Skin turgor

Mucous membranes

Peripheral perfusion

Urine

Mild

4-5%

40-50ml/kg

Normal

Normal

Normal

Normal

Moist

Normal

Reduced

Moderate

6-9%

60-90 ml/kg

↑, Weak

Normal of low

Deep

↓

Dry

Poor

Oliguria

Severe

>10%

100-110 ml/kg

↑↑, feeble

Reduced

Deep & rapid

↓ ↓

Very dry

Poor, cool, extremitas

Marked oliguria

Assessment of the degree of dehydration

2. Hydration :

Source: Nelson W

Management of dehidration

a. Estimated fluid deficit

b. Rehydration

For example : a 10 kg child is assessed to severe

dehydration with an estimated 10%

Dehydration 10%, 10 kg

EFD : 100 ml x 10 = 1000 ml

Initial fluid resusitation : 20ml/kg (20-30’)

Reassess the clinical state

Improved Non improvement

First 8h : 50% rest fluid deficit +

fluid maintenance

Second 16h : 50% rest fluid deficit +

fluid maintenance

Repeat : 20 ml/kg/20-30’

Resassess

- Respiration

- Circulation

- Mental status

Choice of the fluid :

Rehydration : Isotonic crystalloid

Maintenance : Hypotonic crystalloid

20

40

60

80

100

120

140

160

H+

K+

Cl+

K+

Na+

HCO3

Cl+

Cl+ K+

HCO3 Na+

Stomach Small bowel Diarrhea

Electrolyte composition of stomach, small bowel and diarrhea

3. Electrolyte im balance

Electrolytes

Sodium : 3-4 mEq/kg/day

Potassium : 2-3 mEq/kg/day

Chloride : 2-3 mEq/kg/day

Calcium : 150-500 mg/kg/day

Phosphorus : 0.5-2 mmol/kg/day

Magnesium : 0.25-0.5 mEq/kg/day

Maintenance electrolyte requirement in children

Source : J Allan Paschall

Hypo Natremia

1. Estimated fluid deficit

2. Resucitation from shock : NS / RL

3. Calculated deficit hourly IV rate

Maintenance + deficit Na- / 24 hours

mEq Na+ = (Desired Na+ - Observed Na+) x weight (kg) x 0.6

4. Infuse D5 0.45 NS or D5 NS or D5 LR

5. Add 10 – 20 mq kcl/l based on renal function and K+ level

Hypokalemia

K : 0.5 – 1 meq/kg (max.20 meq) / 2 hour

Repeat : 4- 8 hours as need

Monitoring : ECG

Hyperkalemia

CaCl : 0.1 – 0.3ml/kg a. 10% solution

CaGluconas : 0.3-1ml/kg a.10% solution

Nabic : 1-2 mEq/kg + mild to moderate hyperventilation

Glucosa + insulin : 0,5g /kg Glucose + 0.1U/kg insulin / 30-60’

III. REPLACEMENT

Intraoperative fluid management

- Maintenance

- Replacement

Replacement

- Third space lossess

- On going lossess

1. First hour, hydrating solution:

Age ≤ 3 year : 25ml/kg, plus item 3

Age ≥ 4 year :15 ml/kg, plus item 3

2. All other hours basic hourly fluid plus item 3 below

Maintenance fluid = 4 mL/kg

Maintenance + trauma = basic hourly fluid

4 mL/kg + mild trauma (2 mL/kg) = 6 mL/kg

4 mL/kg + moderate trauma (4 mL/kg) = 8 mL/kg

4 mL/kg + maximal trauma (6 mL/kg) = 10 mL/kg

3. Blood replacement with 3:1 volume replacement with crystalloid

or colloid, or blood

Guidelines for intraoperative fluids in pediatric patiens

From: Berry Reproduced

Age

Premature infant

Newborn

Infant < 1 y

Child > 1 y

EBV (mL/kg)

90-100

80-90

75-80

70-75

Estimated blood volume (EBV) in pediatric patiens

BLOOD REPLACEMENT

Age

Premature

Newborn

3 mo

1 y

6 y

Mean

45

54

36

38

38

Range

40-45

45-65

30-42

34-42

35-43

Acceptable hct (%)

35

30-35

25

20-25

20-25

Normal hct (%)

Normal & acceptable hematocrit (Hct) values in pediatric patients

Age

1 day

1 week

1 mo

3 mo

0.5 – 5 y

5 – 9 y

12 – 14 y

girls

boys

Mean

18

17

14

12.5

13

13.5

13.5

14

Lower limit

13.5

13

13

9

11.5

12

12

12.5

Normal hemoglobin (g/100mL)

Mean & lower normal hemoglobin levels

in pediatric patients

Dallman & Siimes, Oski & Neiman, and Saarinen & Siimes

1. Blood required =

Hct 1 – Hct 2

Hct 3

X EBV

2. Blood required (PRC) = (Hct 1 – Hct 2) x body weight (kg) x 1.5

(WB) = (Hct 1 – Hct 2) x body weight (kg) x 2.5

Hct1 : Haematocrit before transfusion, the measured

haematocrit

Hct2 : Haematocrit required after transfusion, the desired

haematocrit

Hct3 : Haematocrit of the blood to be given (60% if packed cells)

EBV : Estimated blood volume

BLOOD REPLACEMENT TO USE HAEMOTOCRIT LEVEL

Guidelines for red cell transfusion to neonate and premature

• Shock associated with acute blood loss

• Hb< 13g/100mL, Hct<40%, and presence of pulmonary

failure, cyanotic heart disease, or congestive heart failure

• Comulative loss of 10% or more of the blood volume

within 72 h or less if additional sampling is required

• Hb<80g/100mL, or Hct<25% in a stable neonate with clinical

manifestations of anemia, e.g. tachycardia, tachypnea,

poor feeding

Source: Kevy SV, Gorline JB, in Hemetology of infancy & childhood, 1998

Postoperative Fluid Management

• Maintenance fluid

• Replacement of fluid deficit

• Replacement of other losses

- Chest tube

- Nasogastric tube

- Weeping incision

- Continous slow bleeding

• Correction of electrolyte inbalance

• Maintenance fluid requirement on the first most operation

day are decreased to 2/3 of the usual daily amount

Conclusion

• Fluid therapy for pediatric patients must be based on the knowledge

of the fluid and electrolyte needs in healthy infants and children

on physiologic responses to the surgical procedure

• Formula for fluid therapy are guidelines that need to be revaluated

according the patients response

• Even more than in the adult, improper fluid management in

infants and children can cause life threatening consequences

• The inadverten administration of a seemingly minuscule excess

of fluid may couse problems.

For example :

100 ml fluid in full term neonate is comparable to 1 to 2

liter excess in an dault