Dehydraton in pediatrics

Definition Definition

is defined as an excessive loss of body fluid & electrolytes.

Output is more than input.

Causes Causes

Diarrhea Vomiting Excessive Sweating Diabetes Burns Excessive blood loss caused by

trauma or accident

Pathophysiology of dehydration

Types of dehydration based on severity

Mild : when the total fluid loss reaches 5% or

less .

Moderate : when the total fluid loss reaches 5 - 10% .

Severe : when the total fluid loss reaches more

than 10%, considered an emergency case .

Mild dehydration S&S Mild dehydration S&S

No dehydration Thirsty Conscious Less than 5% of body Weight is

lost.

Moderate dehydration S&SModerate dehydration S&S

Dry skin and mucous membranes

Thirst Decreased urine

output Crying baby with

tears Muscle weakness Drowsiness light head ache

sunken fontanels Decreased BP Increased Pulse

rate (tachycardia) Capillary refill Shallow rapid RR

5 to10 % of body Weight is lost

Severe dehydration S&SSevere dehydration S&S

Extreme thirst Very dry mouth,

skin and mucous membranes

Sunken eyes Sunken fontanels No tears Anuria Dry skin that lacks

elasticity and slowly “bounces back” when pinched into a fold

Rapid heartbeat Rapid and shallow

breath Unconsciousness More than 10 % of

body Weight is loss

Delay Capillary refill for more than 2 seconds

Possible ComplicationsPossible Complications

Permanent brain damage Seizures hypernatremia Hyponatremia hypovolemic shock Kidney failure Coma and death

Tests and diagnosisTests and diagnosis

Blood tests: to check level of

electrolytes. BUN Creatinine

Urine analysis

Diarrhea

Indications for stool studies Toxic appearance Immunocompromised Bloody or invasive Duration > 5days Suspected parasites

Travel Camping Poor Water

TreatmentTreatment

dehydration treatment depends on age,weight , the severity of dehydration and its cause.

Oral rehydration solution (ORS) for mild and moderate dehydration

IV fluid replacement (for sever dehydration)

Treating the cause of dehydration A single dose of ondansetron (Zofran)

oraly(tablet)

Treatment of mild and moderate dehydration Treatment of mild and moderate dehydration

Oral rehydration solution (ORS)

is a simple treatment for dehydration

Contraindications for ORS:1. Severe dehydration.2. Unconsciousness.3. Frequent vomiting attacks.

Continues breastfeeding . A single dose of ondansetron oraly(tablet)

Treatment of sever dehydration Treatment of sever dehydration

NPO. IV fluid replacement.

Daily Maintenance Fluid Requirements

Calculate child’s weight in kg. Allow 100 ml/kg for first 10 kg body

weight. Allow 50 ml/kg for second 10 kg body

weight. Allow 20 ml/kg for remaining body

weight.

Daily Maintenance Fluid RequirementsDaily Maintenance Fluid Requirements

Calculating replacementCalculating replacement

Correction of deficit: Deficit in ml = wt (kg) x % dehydrated x 10

(ideally the pre-dehydration weight should be used).

example : 14 kg child who is 5% dehydrated has a

deficit of 14 x 5 x 10 = 700 ml.

Fluid requirements(burn victim )Fluid requirements(burn victim )

TBSA burned(%) x Wt(kg) x 4 mlexample : a child weighs 15kg,he has his leg

burned TBSA=18 18x15x4=1080ml.

Give half of total requirements in first 8 hour,second half over next 16 hour.

Give IV fluid to the burned victim (child ) If the TBSA is 10% or more .

Rule of nine for measuring TBSARule of nine for measuring TBSA

Calculating Drop rate per minutes Calculating Drop rate per minutes

(Solution) ml x 15 /hr x min

Example :540 ml x15/8 hr x 60 =16 drops per

minute.540mlx15/16x60=8 drops per

minute.

Prevention and home care Prevention and home care

FAMILY EDUCATION: If your child has vomiting or diarrhea more than

four to five times in 24 consecutive hours, start fluid replacement & increasing fluid intake.

Even when you are healthy, drink plenty of fluids every day and drink more when the weather is hot.

Begin fluid replacement as soon as vomiting and diarrhea start -- DO NOT wait for signs of dehydration.

Remind family that fluid needs are greater with fever, vomiting, or diarrhea .

Notify physician immediately in case of continues vomiting and diarrhea.

teach the mother how to prepare ORS at home

Prevention and home care Prevention and home care

Approach

Approach to Peds Dehydration

1) Initial Resuscitation

2) Determine % dehydration

3) Define the type of dehydration

4) Determine the type and rate of rehydration fluids

5) Final considerations

The gospel according to Rob Hall


1) Initial Resuscitation2) Determine % dehydration




Initial Resuscitation

ABCs Initial fluid bolus

20cc/kg of NS or Ringers Appropriate in all types of dehydration Reassess q5mins and repeat x 3

Initial hypoglycemia 5cc/kg of D10W in infants 2cc/kg of D25W in children

Think about Shock DDx if unresponsive to 3 attempts at NS bolus

Initial Resuscitation

Fluid Controversy… NS / RL

Theoretical risk of acidosis with NS “Dilutional acidosis” with addition of NaCl

to the extracellular fluid Ringers lactate has some HCO3



2) Determine % dehydration3) Define the type of dehydration



Determine % Dehydration

What are the best clinical markers?

Prolonged cap refill

Sunken eyes Poor overall

appearance Sunken

fontanelle Absent tears

Increased HR Weak Pulse Dry mucous

membranes Abnormal resp

pattern Abnormal skin

turgor or tenting

Determine % Dehydration

Does lab work help you in determining the degree of dehydration?

What lab values do people use to assess severity of dehydration?

Tests such as BUN and bicarbonate are only helpful when results are markedly abnormal

A normal bicarbonate concentration reduces the likelihood of dehydration

No lab test should be considered definitive for dehydration




3) Define the type of dehydration4) Determine the type and rate of

rehydration fluids


Define the type of dehydration

Three major classes of dehydration based on relative losses of Na and Water

1) Isonatremic dehydration (80%)2) Hypernatremic dehydration (15%)3) Hyponatremic dehydration (5%)

Thanks to Rob Hall for any details

Body FluidsICF (mEq/L) ECF (mEq/L)

Sodium 20 135-145 Potassium 150 3-5 Chloride --- 98-110 Bicarbonate 10 20-25 Phosphate 110-115 5 Protein 75 10

1. Isonatremic dehydration

By far the most common Equal losses of Na and Water Na = 130-150 No significant change between

fluid compartments No need to correct slowly

2. Hypernatremic Dehydration

Water loss > sodium loss Na >150mmol/L Water shifts from ICF to ECF Child appears relatively less ill

More intravascular volume Less physical signs Alternating between lethargy and

hyperirritability

Hypernatremic Dehydration

Physical findings Dry doughy skin Increased muscle tone

Correction Correct Na slowly If lowered to quickly causes

massive cerebral edema intractable seizures

3. Hyponatremic Dehydration

Sodium loss > Water loss Na <130mmol/L Water shifts from ECF to ICF Child appears relatively more ill

Less intravascular volume More clinical signs Cerebral edema Seizure and Coma with Na <120

Hyponatremic Dehydration

Correction Must again be performed slowly unless

actively seizing Rapid correction of chronic hyponatremia

thought to contribute to….Central Pontine Myelinolysis

Fluctuating LOC Pseudobulbar palsy Quadraparesis







Determine the type and rate of rehydration fluids

Oral Rehydration Therapy (ORT) vs Intravenous therapy (IVT)

“ To poke or not to poke, that is the question”

ORT

Fluid replacement should be over 3-4hrs

50ml/kg for mild dehydration 100ml/kg for moderate dehydration

10ml/kg for each episode of vomiting or watery diarrhea

ORT

Contraindications to ORT Severe dehydration (≥10%) Ileus or intestinal obstruction Unable to tolerate (Persistent vomiting) Signs of shock Decreased LOC or unconscious Unclear diagnosis Psychosocial situations

Oral rehydration solutions (ORS)

OsmolesmOsm/L

Glucosemmol/L

NamEq/L

ClmEq/L

HCO3mEq/L

KmEq/L

WHO formulation 330 110 90 80 30 20

Pedialyte 270 140 45 35 30 20

D5W / 0.45% saline 454 300 77 77 0 0

NGT???

Is there a role for nasal gastric tube oral rehydration?

When caregivers are unwilling to perform ORT or when it is required overnight continuous nasogastric tube infusion is preferred over intravenous infusion

When to start feeding again?

Severe Dehydration

Management of severe dehydration requires IV fluids

Fluid selection and rate should be dictated by

The type of dehydration The serum Na Clinical findings

Aggressive IV NS bolus remains the mainstay of early intervention in all subtypes

Isonatremic Dehydration

Calculate the fluid deficit Deficit (cc’s) = % dehydration x

body wt

D5½NS is fluid of choice

(½ deficit – the bolus) over the first 8hrs

Add maintenance and any ongoing losses to above

Further ½ the deficit replaced over the next 16hrs

Monitor electrolytes and U/O

Alternative – rapid approach

Hypernatremic Dehydration

Fluid deficit =• Replace with D50.2%NS• Replace over 48hrs• Reduce sodium by no more than 10mEq/L/24hrs

Water deficit (in L) = [(current Na level in mEq/L ÷ 145 mEq/L) - 1] X 0.6 X weight (in kg)

(½ deficit – the bolus) over the first 24hrs Add maintenance and any ongoing losses to

above Further ½ the deficit replaced over the next 24hrs

Hyponatremic dehydration

Na deficit =(Nadesired- Nacurrent) x 0.6 x Weight (kg)

154 mEq in NS 77 mEq in D5½ NS 513 in 3% saline

rate at 0.5mEq/L/hr

Hyponatremic Dehydration

If seizing Correct with 3% Saline bolus Target a Na of 120 Further correction beyond this with D5½ NS

If not Seizing Correct with D5½ NS Target a Na of 130

Watch for Central Pontine Myelinolysis More likely in chronic hypo-Na with less Sx Correct slowly at rate of 0.5mEq/L/hr







Final considerations

Does and Acid-Base Deficit exist?

Does a potassium disturbance exist?

What is the patients renal function?

Does and Acid-Base Deficit exist?

Acidosis Lactate Ketones Loss of Bicarb in diarrhea

Most will resolve with simple rehydration

Consider HCO3 for pH<7.0

Does a potassium disturbance exist?

K+ losses GI Renal

Remember that K shifts with acidosis and certain therapies

Always insure renal function prior to IV replacement

Rapid Fire Cases

Case 1

2yr F (14kg) 3 days of diarrhea and vomiting

Decreased u/o as per mother

Exam Generally appears well MM dry and no significant tears Skin turgor normal Tachycardic but not tachypneic Cap refill 2 seconds







Answers

Initial resuscitation deferred

% dehydration 5-9% moderate

Dehydration Type Likely Isonatremic

Rehydration fluids ORT Pedialyte

Rate and volumes Moderate

dehydration 100cc/kg = 1400cc

Replace over 3-4hrs Further 10cc/kg with

ongoing losses

Final considerations

None

Case 2

8mo M (8kg) 4 day hx of

severe diarrhea and vomiting No further

ongoing losses

Exam Limp and cold Mottled with weak

rapid pulse Sunken eyes and

fontanelle Cap refill 5s Tenting of skin

LabsNa = 170K = 3.1HCO3 = 18







Answers

Initial resuscitation 160cc NS bolus

% dehydration >10% Severe

Dehydration Type Hypernatremic

Rehydration fluids IV fluids D50.2NS

Rate and volumes Volume deficit =

640cc Correct slowly over

48hrs 39cc/hr over first

24hrs 45cc/hr over next

24hrs

Final considerations Add 20 mEq K to IV

fluids

Case 3

16mo F 3 day Hx of vomiting and diarrhea

Tolerating fluids not solids Good u/o

Exam Appears well with normal vitals Tears + MM moist Cap refill <2s Skin turgor normal







Answers

Send this kid home!!!

Case 4

2 yo M (16kg) 4 day Hx of vomiting

and diarrhea Exam

Appears drowsy but not lethargic

Good tone Tachycardiac and

tachypneic BP normal Very Dry MM Cap refill 3s

LabsNa = 134K = 3.1HCO3 = 16







Answers

Initial resuscitation

320cc of NS % dehydration

>10% Severe

Dehydration Type Isonatremic

Rehydration fluids D5½ NS

Rate and volumes Volume deficit =

10% x 16kg= 1600mls

110cc/hr over first 8hrs

100cc/hr over next 16hrs

Final considerations Add 20 mEq K to IV

fluids Watch for metabolic

acidosis to resolve

Case 5

1yo F (10kg) 4 day Hx of

severe diarrhea and vomiting

Exam Lethargic and limp Weak rapid pulse Fontanelle sunken Cap refill 5s Cool and mottled Tenting of skin

Labs Na = 114 K = 3.4 HCO3 = 18

During your exam the patient starts Seizing







Answers

Initial resuscitation 200cc NS

% dehydration >10% Severe

Dehydration Type Hyponatremic

Rehydration fluids IV Initially 3% saline D5½ NS after above

Rate and volumes Initially correct to

Na of 120 with 3%= 70cc bolus Then correct to Na

of 130 with D5½ NS at rate of 0.5mEq/L/hr

= 39cc/hr Final

considerations Add 20 mEq K to IV

fluids

THANK YOU

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Health & Medicine

Dehydraton in pediatrics