Fluids and Electrolytes Flashcards
Outpatient management of gastroenteritis: ondansetron MoA
Selective 5-HT3 receptor antagonist
Recommendation for ondansetron
Administer as a single dose, PO or IV, to assist patients in tolerating ORT
Ondansetron ADEs
QTc prolongation, arrhythmias
Outpatient management of gastroenteritis: probiotics MoA
assists in re-establishing normal intestinal flora, suppresses growth of pathogenic microorganisms through lactic acid, resulting in an acidic environment
Probiotic recommendation
Low quality of evidence to support universal recommendation
Outpatient management of gastroenteritis: zinc
Not really used in developed countries
Dosage forms of zinc are expressed in the _____ form, which is ______% elemental zinc.
Expressed in the salt form, which is 23% elemental zinc
Elemental zinc dose: <6 months
10mg/day x10-14 days
Elemental zinc dose: ≥6 months and children
20mg/day x10-14 days
Avoid what in gastroenteritis treatment in children?
Loperamide, antisecretory agents like bismuth subsalicylate and metoclopramide
Dehydration and percent changes in weight: mild dehydration in infants
1-5%
Dehydration and percent changes in weight: mild dehydration in older children
1-3%
Dehydration and percent changes in weight: moderate dehydration in infants
6-9%
Dehydration and percent changes in weight: moderate dehydration in older children
4-6%
Dehydration and percent changes in weight: severe dehydration in infants
> 10%, ≥15% is shock
Dehydration and percent changes in weight: severe dehydration in older children
> 6%, ≥9% shock
Signs of mild dehydration in infants and older children (generally)
Overall, pretty much normal, but may have an increased pulse, decreased urine output, and slightly dry buccal mucosa
Signs of moderate dehydration in infants and older children (generally)
Tachycardia, may have low BP, everything else is dry, sunken, cool, thirsty, may have slightly altered mental status
Signs of severe dehydration in infants and older children (generally)
Basically, take the moderate dehydration signs and symptoms and make them more sunken, not drinking at all, rapid and weak pulse, almost comatose
Formula for severity of dehydration
[pre-illness weight (kg)- illness weight (kg)]/pre-illness weight x 100%
Fluid deficit formula
% dehydration x pre-illness weight / 100
Components of an IVF bag
Sodium, dextrose, potassium
Sodium concentration in IVF bags (typically)
NS!
Dextrose concentration in IVF bags (typically)
D5W!
Potassium concentration in IVF bags (typically)
20 mEq/L
Additional electrolytes in IVF bags
Mg, phosphate, calcium based on individual needs
Standard negative anion added to IVF bags
Chloride
Formula for MIVF rate calculation: weight <10kg
100ml/kg
Formula for MIVF rate calculation: weight 10-20kg
1000mL+50ml/kg (each kg >10kg)
Formula for MIVF rate calculation: >20kg
1500ml+20ml/kg(each kg >20kg)
Goal of therapy for dehydration treatment
Restore fluid and electrolyte balance in combination with early introduction of appropriate food and PO liquids as directed
What will determine the treatment strategy selected?
Degree of dehydration
Treatment for mild-moderate dehydration
ORT
ORT dosing: mild dehydration
50ml/kg over a 4-hour period, reassess q2h
ORT dosing: moderate dehydration
100mg/kg over a 4-hour period, reassess q2h
ORT dosing: add an additional ________ per each _________
Add an additional 10ml/kg per each loose stool/vomiting episode for both mild and moderate dehydration
Severe dehydration treatment (generally)
IVF
Phase I of severe dehydration treatment
Give IV bolus fluids
Phase I IVF bolus dose
10-20ml/kg/dose of NS or LR over 30-60 minutes; repeat up to 3 times PRN
Phase II of severe dehydration treatment
maintenance replacement
Phase II treatment: first 8 hours
calculate and replace fluid deficit
Phase II treatment: next 16 hours
calculate and provide maintenance rate
Monitoring parameters for dehydration treatment
Normalization of BP
Adequate urine output for age/weight
Improvement in clinical signs and symptoms of dehydration
Normalization of serum electrolytes/laboratory parameters
