The document provides information on pediatric fluids and electrolytes. It discusses how a child's body composition changes with age, describing them as having higher percentages of total body water when younger. It also outlines the three main components of fluid therapy: maintenance fluids, deficit fluids, and replacement fluids. Methods for calculating fluid rates are presented, including the Holliday-Segar method. Types, degrees, and treatment approaches for dehydration are defined. Oral and intravenous rehydration protocols are described for various clinical scenarios.

1. Pediatric Fluids and
Electrolytes
Rachel Sykes, PharmD, BCPS
Clinical Assistant Professor
Ernest Mario School of Pharmacy
Rutgers University
Saint Barnabas Medical Center
September 27, 2007
Objectives
• Describe how pediatric body composition
changes over time
• Identify the three main components of fluid
therapy
• Calculate the maintenance fluid rate for a
child using the Holliday -Segar Method
• Determine appropriate fluid components
for a hospitalized child
Objectives
• Calculate fluid rates for a child with
dehydration
• Determine a 3% saline volume and rate for
a child with severe hyponatremia
• Recommend an oral rehydration regimen
for a child with mild dehydration
1

2. Body Fluids
• Total Body Water =
Extracellular Fluid (ECF) + Intracellular Fluid (ICF)
• ECF = Plasma + Interstitial Fluid
• Total Body Water expressed in terms of % body
weight (adolescent or adult):
ICF (30-40%) Interstitial Plasma
(15%) (5%)
Changes in Body Water
Behrman RE, Kliegman RM, Jenson HB. Nelson Textbook of
Pediatrics. 17 th Ed. Philadelphia, PA: Elsevier Science; 2004.
Change in Body Composition
Miller RD. Miller’s Anesthesia . 6 th Ed. Philadelphia, PA: Elsevier Science; 2005.
2

3. “Babies are like bags of water”
Full-term: 75% water
http://chfs.ky.gov/dph/ach/ecd/newbornscreening.htm
http://www.inmagine.com/rubberball-single-image-set-photos/Rubberball-rbv005
Premature babies: 83% water
http://www.sciencemuseum.org.uk/antenna/babybrainscans/
http://www.jupiterimages.com/popup2.aspx?navigationSubType=itemdetails&itemID =22684522
Regulating Water and
Electrolytes
• What makes someone thirsty?
– Increase in serum osmolarity
– Volume depletion
• Dehydration causes increased serum
osmolarity
– Antidiuretic hormone (ADH) released
– SIADH – ADH is released even when the
serum osmolarity is low
3

4. Fluid Therapy
• Three types of fluid therapy
– Maintenance fluid Fluid to compensate for
– Deficit ongoing normal losses
– Replacement
Fluid to compensate Fluid to
for ongoing losses compensate for
during medical fluid loss prior to
treatment medical treatment
Case #1
• A 5 year-old boy is admitted to the hospital after
a bike accident where he lost a significant
amount of blood. During his hospital stay he has
a chest tube placed for a few days. The patient
is treated in the hospital for one week and is
then discharged home.
• What types of fluid therapy does he need?
Maintenance Fluid
• Where does the body lose fluid?
– Urine
– Insensible losses
• Respiratory, skin, feces
– Intrinsic losses
• By -product of metabolism
• What makes kids different?
– Higher metabolic rate and evaporative
losses
4

5. Insensible Losses
• Factors affecting insensible
losses
– Respiratory rate
• Age
• Pain
• Ventilator
– Environmental temperature
• Phototherapy
– Congenital skin defects
Gastroschisis
http://www.nlm.nih.gov/medlineplus/ency/imagepages/9028.htm
Omphalocele
http://www.nlm.nih.gov/medlineplus/ency/imagepages/9030.htm
5

6. Respiratory Rates
Respiratory Rate
Age Group
(per minute)
Infant 30-60
Toddler 24-40
Preschool Age 22-34
School Age 18-30
Adolescent 12-16
HazinskiMF. Anatomic and physiologic differences between children andadults.
Deficit Fluids
• Causes of dehydration
– Inadequate intake
– Blood loss
– Fever
– Catabolic state
• Extra solutes, need extra fluid in order to excrete
Replacement Fluids
• Type of fluids replaced depends on what ’s
being lost
– Cerebrospinal fluid drains
• Generally replaced with normal saline
– Chest tube drains
• Generally replaced with albumin, particularly after
heart surgery
6

7. Calculating Maintenance
Fluids
• Holliday-Segar Method
Fluid per day Rate per hour
1st 10 kg 100 mL/kg/day 4 mL/kg/hr
Next 10 kg 50 mL/kg/day 2 mL/kg/hr
Weight > 20 kg 20 mL/kg/day 1 mL/kg/hr
This method assumes that 100 kcal
expended requires 100mL water
Maintenance Fluid Example
Calculations
Calculate the maintenance fluids in mL/day and
mL/hr for the following patient weights:
• 25kg
• 4kg
• 16kg
Electrolyte Maintenance
Requirements
Sodium 2 - 3 mEq/kg/day
Potassium 1 - 2 mEq/kg/day
Chloride 3 - 5 mEq/kg/day
• Chloride needs are generally met by
meeting sodium and potassium
requirements with NaCl and KCl
7

8. What is the usual maintenance fluid
for a child?
• 28 kg, well-hydrated child - What fluid would you
recommend?
• FIRST - calculate the amount of fluid you need
• NEXT - calculate how much sodium and
potassium you need
• FINALLY - pick a fluid based upon what is
commercially available if you can
Increased Maintenance
Requirements
• Fever
• Vomiting
• Hyperventilation
• Hypermetabolic states
• High environmental temperature
• Intestinal losses
• Burns
Decreased Maintenance
Requirements
• Increased environmental humidity
• Hypothermia
• Hypometabolic states
8

9. Dehydration
Clinical Signs of Dehydration
• Weight loss • Babies - sunken
– Weigh children fontanelle
frequently
• Decreased urine
• Thirst
production
• Decreased skin turgor
• Increased urine
• Dry mucous
membranes specific gravity
• Lack of tears • Increased heart rate
• Decreased blood
pressure
What are the implications of
dehydration for drug therapy?
Anterior Fontanelle
http://commons.wikimedia.org/wiki/Image:Human_anterior_fontanelle_1_month_dscn1449.jpg
9

10. Degree of Dehydration
• Need to accurately monitor patient weights
frequently
• Fluid deficit (L) = PIW (kg) – IW (kg)
– PIW = Pre-illness weight
– IW = Illness weight
• % Dehydration = PIW (kg) – IW (kg) x 100%
PIW (kg)
Degree of Dehydration
Mild Moderate Severe
Older 3% 6% 9%
Child (30 mL/kg) (60 mL/kg) (90 mL/kg)
5% 10% 15%
Infant
(50 mL/kg) (100 mL/kg) (150 mL/kg)
Degrees of Dehydration
Clinical Signs Mild Moderate Severe
Weight Loss (%) 5 10 15
Hyperirritable to
Behavior Normal Irritable
lethargic
Thirst Slight Moderate Intense
Mucous May be
Dry Parched
membranes normal
Tears Present ± Absent
Anterior
Flat ± Sunken
Fontanelle
10

11. Degrees of Dehydration
Clinical Signs Mild Moderate Severe
Eyes Normal Deepset Sunken
Skin Turgor Normal ± Increased
Blood
Normal Normal Decreased
Pressure
Skin color Normal Pale Gray / mottled
Full, normal
Pulse Rapid Rapid, weak
rate
Markedly
Urine output Decreased Anuria
decreased
Types of Dehydration
• Isotonic
– Serum Na = 130-150 mEq/L
– 80% of dehydrated patients
• Hypertonic
– Serum Na > 150 mEq/L
– 15% of dehydrated patients
• Hypotonic
– Serum Na < 130 mEq/L
– 5% of dehydrated patients
Dehydration – Developing a Plan
of Action
1. Estimate the degree of dehydration
2. Determine the type of dehydration
• This will lead you to your Plan!
• Plan will have 3 phases
11

12. Phase I – Rapid phase
• Goal: Restore circulation, reperfuse brain,
kidneys
• Mild-Moderate
– 10 – 20 mL/kg bolus given over 30 – 60
minutes
• Severe
– May repeat bolus as needed
• Fluids – something isotonic such as NS or
lactated ringers (LR)
Hypotonic / Isotonic Dehydration
Phase 2 – Replacement Phase
• Goal: Replace deficit of fluids and
electrolytes
• Amount:
– 1/3 daily maintenance + ½ deficit
• Fluids:
– D5 ½ NS + 20-30 mEq KCl
• Add KCl only if patient has voided
• Time: Over 8 hours
Hypotonic / Isotonic Dehydration
Phase 3 – Stabilization Phase
• Goal: Transition to maintenance fluids
• Amount:
– 2/3 daily maintenance + ½ deficit
• Fluids:
– D5 ¼ NS + 20-30 mEq KCl
• Time: Over 16 hours
12

13. Hypertonic Dehydration
Phase 2 – Replacement Phase
• Goal: Replace deficit of fluids and electrolytes
and daily maintenance
• Amount:
– Deficits + daily maintenance
• Fluid:
– D5 ¼NS + 20-30 mEq/L KCl
• Give over 24-48 hours
• IMPORTANT: Lower serum Na by no more than
10-12 mEq/L/day
Hypertonic Dehydration
Phase 3 – Replacement Phase
• Goal: Replace ongoing losses and
transition towards maintenance fluid
therapy
• Amount:
– Replacement + daily maintenance
• Fluid:
– D5 ¼NS + 20-30 mEq/L KCl
Acute Severe Hyponatremia
• Serum Na < 120, CNS symptoms
• Administer 3% saline
• Total volume =
– [(130 - serum Na)(0.6)(wt in kg)] x 2
• Give 1/2 total in < 1 hr and remainder over
the next 2 hours if symptoms persist
13

14. Oral Rehydration
• Effective, safe, inexpensive
• Indications
– Replacement fluid for mild dehydration
– Following Phase I volume resuscitation in moderate
dehydration
• Contraindications
– Severe dehydration
– Electrolyte abnormalities
– Ileus or gastric obstruction
www.rehydrate.org
Rehydration Solutions
Recommendation: Glucose 2 - 2.5 g/dL
Sodium 50-75 mEq/L
Glucose Sodium Potassium
(g/dL) (mEq/L) (mEq/L)
Pedialyte 2.5 45 20
Gatorade 5.9 21 2.5
Apple Juice 11.9 0.4 26
Milk 4.9 22 36
Water 3 0.5
http://almostgirl.coffeespoons.org/?p=1131
http://www.yummy.com/subcategorylist.aspx?cGw8n4AckUu5BAvSiFaUNV
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Oral Rehydration
• Patient vomiting
– 5-10mL Q 5-10 minutes and increase as
tolerated
• Mild Rehydration
– Deficit replacement: 50 mL/kg over 4 hours
• Moderate Rehydration
– Deficit replacement: 100 mL/kg over 4 hours
14

15. Hyperkalemia
• Can cause life-threatening arrhythmias
– Bradycardia
– Ventricular dysrhythmias
• First determine why the serum level might
be high
– Heel stick?
– KCl in fluids?
Blood Collection in Newborns
http://health.state. ga. us/programs/nsmscd/screening_form.asp
http://www.nlm.nih.gov/medlineplus/ency/imagepages/2961.htm
Hyperkalemia
• Treatment
– Calcium
– Bicarbonate
– Insulin (with glucose)
– Albuterol
15

16. Case #3
• JW, a 16 month old boy (11kg), is brought
into your pharmacy by his mother. JW’s
mom says that he had a mild bout of
diarrhea a few days ago, and she is still
noticing fewer wet diapers. Otherwise, he
has no symptoms.
JW’s mother would like to know what she
should do. What do you recommend?
Case #4
• DR is a 4 year old girl (16kg) who presents
to the emergency room with fatigue,
headache, generalized malaise, and
severe gastrointestinal distress. The ER
team gets a chem-7 and discovers her
sodium to be 118. They would like to give
3% NS and ask you for a recommendation
on how much to give, and at what rate.
Case #5
• LM is a 4 month old, 7kg (preillness) girl
who presents to the ER with a sunken
fontanelle, dusky skin, lethargy, and is not
crying. She has not urinated in several
hours. Current weight is 6kg. Her sodium
is 137.
What type and degree of dehydration does
she have?
How do you recommend treating her?
16

17. Case #5
• How do I double-check my answer?
It’s easy! Just add up all
the fluid you gave.
It should equal the deficit
+ the daily maintenance
requirement.
17