Basics in Dehydration & it's management in paediatric practice. Prepared by Dr. Viduranga Edirisinghe on request by Prof. Wasantha Karunasekara. [2013 Aug]
2. WHAT IS DEHYDRATION?
Dehydration is simply the excessive loss of body water resulting a decrease in total body water
Total Fluid Loss >Total Fluid Intake
There is a NET FLUID LOSS
Fluid lost from both intravascular & extravascular compartments
Intravascular loss – Hypovolaemia & Serum osmolality
Extravascular loss – Impairment of cellular function & Loss of tissue laxity
Often there is an associated electrolyte loss with diarrhoea
Sodium is the most affected electrolyte – Hypernatremia or Hypernatremia
4. ASSESSMENT
When you get a child with vomiting or diarrhoea always look for dehydration.
What is there to look for…??
Is there any dehydration?
If so how bad is it?
Infants are at a higher risk of developing dehydration. Why?
1) High surface area to weight ratio
2) High basal fluid requirement
3) Immature renal tubular reabsorption process
4) Inability to gain access to fluids when thirsty
5. ASSESSMENT
History Examination
Increased thirsty Body weight loss
Reduced level of consciousness (Drowsy) Anterior fontanelle - Sunken
Reduced urine output Sunken eyes
Reduced/Absent tears
Dry mucous membranes
Loss skin turgor
Pulse rate – Increased
Capillary refill time – Prolonged (>2 seconds)
Blood Pressure – Low
Respiration – Deep & Rapid
6. ASSESSMENT
• Weight loss < 5%
• Thirst & low urine output maybe present
• Physical examination is normal
Mild
(No signs of
dehydration)
• Weight loss 5-10%
• Thirsty & drinks eagerly
• Restless or irritable, other signs of dehydration present.
Moderate
(Some dehydration)
• Weight loss > 10%
• Not able to drink or drinks poorly
• Lethargic or unconscious, signs of dehydration are very severe.
Severe
(Severe dehydration)
7. MANAGEMENT
Management of acute diarrhoea
Prevention of Dehydration
Management of Dehydration
Maintenance of Nutrition
Reducing the Duration of Diarrhoea
DrugTreatment
When to Discharge
Parent Education
Notification (if necessary)
Post Gastroenteritis Syndrome / Lactose Intolerance
8. PREVENTION OF DEHYDRATION
Give the child more fluids than usual to prevent dehydration.
Home based fluids & ORS should be used.
As a guide approximately 50ml should be give after each stool or vomiting.
Watch for the signs of dehydration.
9. MANAGEMENT OF DEHYDRATION
There are 3 pillars in management of dehydration.
1.) Correction of existing fluid deficit
2.) Replacement of ongoing losses
3.) Providing the normal daily requirement
When you are seeing the child for the 1st time, a dehydrated child has already lost
a portion of his total body water.This amount is called the “Existing fluid deficit”.
Your 1st concern should be to replace that volume of fluid with in a reasonable
time.
10. MANAGEMENT OF DEHYDRATION
(EXISTING FLUID DEFICIT – HOW DO I FIND IT?)
Degree of dehydration (% of body weight) Existing fluid deficit
Mild (No signs of dehydration) <5% < 50ml/Kg
Moderate (Some dehydration) 5-10% 50-100ml/Kg
Severe (Severe dehydration) >10% > 100ml/Kg
Ex: existing loss of a 5kg weighing boy presented to you with “Some dehydration” is 250 to 500 ml.
• This amount should be given over first 4 hours of presentation.
• Unless the child is severely dehydrated or vomiting frequently & severely, this deficit should be
preferably replaced orally with ORS.
• Vomiting does not prevent successful use of ORS.
11. MANAGEMENT OF DEHYDRATION
(EXISTING FLUID DEFICIT – IFTHE CHILD IS SEVERELY DEHYDRATED?)
If the child’s level of consciousness is reduced airway, breathing & circulation
should be assessed.
Need parenteral (IV or IO) rapid fluid replacement.
100ml/Kg IV Hartmann solution (or Normal Saline) should be given as follows.
Reassess the child in every hourly & increase the infusion rate if not improving.
Age 30ml/Kg 70ml/kg
Infants (<12 months) 1 hour 5 hours
Older children ½ hour 21/2 hours
12. MANAGEMENT OF DEHYDRATION
(DEFICIT CORRECTED – WHAT NOW?)
Even thought the fluid deficit is corrected the child is still losing fluids with each
bout of vomiting & stool.
This is called the “Ongoing Loss”
Replacement of ongoing losses.
Give 10-20ml of ORS or any other oral fluid for each bout of vomiting or stool.
Depending on the stool volume or volume of vomitus fluid intake should be
increased.
13. MANAGEMENT OF DEHYDRATION
Providing normal daily fluid requirement
- Continue breast feeding as usual.
- If on formula milk, continue the same volume in the same dilution.
- Offer as much fluid as possible to drink in addition to ORS or parenteral fluid.
15. REFERENCE
"Definition of dehydration" at medicine net
National guidelines on “Management of gastroenteritis in children”, Ministry of
Healthcare & Nutrition.
Lissauer,Tom.Clayden, Graham. (Eds.) (2007) Illustrated textbook of paediatrics
/Edinburgh ; Mosby/Elsevier