Pediatric Dosing Flashcards
Is there a standard dose for pediatric medicines?
NO
List some reasons as to why there is not a standard dose for pediatric medicines?
Rapid child growth is accompanied with changes in:
- absorption
- elimination
- metabolism
- distribution
At what age will children usually have mature and active enzymes as well as an adult level GFR?
2 years old
What anatomical items alter the distribution of a pediatric drug?
Fat and water content – changes with childhood
What are 2 ways that a pediatric dose can be written?
- mg/kg/day
2. mg/kg/dose
What must a child’s weight in pounds be converted to and how?
Kg
== divide lbs by 2.2
(1 kg = 2.2 lb)
The starting dose can be based on what 3 things for a child?
Age
Weight
Body Surface Area
If a drug is based off a child’s body surface area, what is likely an attribute of the drug?
TOXIC
Explain how to calculate a dose if a child weighs 22 lbs, the dosing range is 90 mg/kg/day and they want to give 2 doses a day.
- 22 lbs/2.2 = 10 kg
- 10 kg X 90 mg/kg/day = 900 mg/day
- 900 mg/2 = 450 mg twice a day
What dose is often considered the maximum dose for a child?
Adult dose = Maximum dose
Body Surface Area is more accurate with dosing but is only used when? What is an example?
With drugs that have a high risk of toxicity
– chemo drugs
What are the parameters for when dosing by weight is accurate?
< 18 yo
< 40 kg
If a child weighs more than 40 kg, dosing by weight is not as accurate. What dose should you use?
Adult dose
With a child that weighs more than 40 kg, you should use weight based dosing unless it exceeds ____
Adult dose
Can mg/kg/dose or /day be abbreviated with /d?
NO
What measurement should meds be ordered in?
mg
Normally, how much water is needed for every _____ of energy expended?
100 mL of water needed for every 100 kcal/kg of energy expended
What classifies insensible water loss?
Water loss that is not perceived like skin and respiratory tract
What classified sensible water loss?
Sweat, urine and stool
What does the Holliday - Segar Method calculate?
Fluids needed
The 4-2-1 rule (holliday-segar method) calculates?
Fluids needed for HOURLY replacement
Describe the HOURLY fluid replacement rule (4-2-1)?
- < 10kg = 4 ml/kg/hr
- 10 - 20 kg = 40 ml + 2 ml/kg for every kg above 10 kg
- > 20 kg = 60 ml + 1 ml/kg for every kg above 20 kg
Describe the HOURLY fluid replacement rule (4-2-1)?
- < 10 kg = 4 ml/kg/hr
- 10 - 20 kg = 40 ml + 2 ml/kg for every kg above 10 kg
- > 20 kg = 60 ml + 1 ml/kg for every kg above 20 kg
If you are concerned about hypoglycemia, what can be added to the fluids?
Dextrose
Ex. What is the hourly and daily fluid maintenance replacement amount for a 25 kg child.
60 ml + 1 X 5 = 65 ml/hr
=> Daily = 65 X 24 = 1560 ml/day
Ex. What is the hourly fluid maintenance for a 5 kg child?
4ml X 5 kg = 20 ml/hr
With Rehydration, what type of fluid should you use?
Isotonic fluid always
Rehydration fluids are always isotonic fluid. Maintenance fluids can be either 1/2 or normal saline. What is the benefit of normal saline? (isotonic)
Prevents against hyponatremia
– especially with adding KCl and Dextrose
What is normal saline?
0.9% NaCl
What are the mEq of Na and Cl in normal saline?
154 mEq per liter
If you have 154 mEq of Na or Cl, what type of saline do you have?
Normal saline = 0.9% NaCl
In order to determine the degree of dehydration in a child, what is beneficial to have?
Pre-weight and post-weight
With dehydration, what fluids are needed?
Replacement fluids for what was lost + MAINTENANCE hourly fluids
With replacement fluids with dehydration, what is the rate of replacement over 24 hours?
1/2 replaced in the first 8 hours
1/2 replaced in the next 16 hours
Ex. Determine how much fluid is lost if a 20 kg child is 10% dehydrated
20 kg X 0.1 = 2 kg = > 2000 mg(cc) fluids LOST = replacement fluids
If a dehydrated child (20 kg) needs 2000 ml of replacement fluids, what else must be added to that?
Maintenance hourly fluids
= 60 ml/hr
What bolus of isotonic fluid is given for dehydration?
10-20 cc/kg/bolus
4 signs of dehydration in a child?
Abnormal appearance
Dry mucus membranes
No tears
Cap refill > 2 seconds
4 signs of dehydration in a child?
Abnormal appearance
Dry mucus membranes
No tears
Cap refill > 2 seconds
