Fluid and Electrolytes

Question 1

Causes of dehydration

Answer 1

fever, gastrointestinal losses (viral gastroenteritis), sweating/heat/burns, polyuria (DKA), imbalance of sodium/water (DI, SIADH)

Question 2

Mild dehydration percent

Answer 2

Infants: 1-5%
Children: 1-3%

Question 3

moderate dehydration percent

Answer 3

infants: 6-9%
children: 4-6%

Question 4

severe dehydration percent

Answer 4

infants: >10% (>15% shock)
Children: >6% (>9% shock)

Question 5

mild dehydration

Answer 5

increased pulse, decreased urine output, slightly dry mucosa

Question 6

moderate dehydration

Answer 6

tachycardia, low BP, oliguria, dry mucosa, sunken fontanelle and eyes, decreased tears, thirsty

Question 7

severe dehydration

Answer 7

rapid and weak pulse, very low BP, oliguria, parched mucosa, very sunken fontanelle and eyes, no tears, ams, unable to drink

Question 8

severity of dehydration calculation

Answer 8

[(pre illness wt - illness wt) / pre illness wt] x 100% (kg)

Question 9

Fluid deficit (L)

Answer 9

% dehydration x pre illness wt / 100

Question 10

mild to moderate rehydration

Answer 10

ORT

Question 11

severe rehydration

Answer 11

IVF

Question 12

mild ORT dosing

Answer 12

50 mL / kg over 4 hours
reassess every 2 hours

Question 13

moderate ORT dosing

Answer 13

100 mL / kg over 4 hours
reassess every hour

Question 14

ORT dosing pearl

Answer 14

add 10 mL / kg for each episode of loose stool or vomiting

Question 15

phase 1 severe rehydration

Answer 15

initial replacement- bolus
10-20 mL/kg/dose of NS or LR
over 30-60 min
repeat up to 3 times based on s/s

Question 16

phase 2 severe rehydration

Answer 16

maintenance replacement
1st 8 hrs: replace fluid deficit
next 16 hrs: maintenance rate

Question 17

monitoring parameters of rehydration

Answer 17

normalize BP, adequate urine output, improve clinical s/s, normalize serum electrolytes and lab parameters

Question 18

components of maintenance IVF

Answer 18

sodium (NS, 1/2 NS, 1/4 NS)
dextrose (D5W, D10W, 12.5%)
potassium (20 mEq/L)
*provide negative anion when giving positive anions (chloride)
ex. potassium chloride (or acetate)

Question 19

maintenance IVF rate (4-2-1 method)

Answer 19

<10 kg: 4 mL/kg/hr
10-20 kg: 40 mL/hr + 2mL/kg/hr x (wt-10)
>20 kg: 60 mL/hr + 1 mL/kg/hr x (wt-20)

Question 20

maintenance IVF rate (holiday segar- 24 hr requirement)

Answer 20

<10 kg: 100 mL/kg
10-20kg: 1000 mL + 50 mL/kg for each kg >10kg
>20 kg: 1500 mL +20 mL/kg for each kg >20kg

Question 21

Max MIVF rate

Answer 21

100 mL/hr

Question 22

gastroenteritis treatment

Answer 22

ondansetron (0.15-0.3 mg/kg/dose)
probiotics (lactobacillus or saccharomyces)
zinc (not rec in developed countries, 10-20 mg/day)

Question 23

ondansetron dosing

Answer 23

0.15 mg/kg/dose OR
8-15 kg: 2mg/dose
15-30 kg: 4mg/dose
>30kg: 8mg/dose