3 Fluid and Electrolyte Management Rushing Flashcards
(25 cards)
What is the body fluid composition like for a newborn?
Full term newborn: 75-80% total body water. 1st week of life: decrease by 4-5%. 1 year: decrease to adult levels 60%. Extracellular water content decreases with total body water content from 45% (at birth) –> 20-25% of adult levels by 1 year of age
What component is the driving force in Plasma water?
Sodium
What component is the driving force in Intracellular fluid compartment?
Potassium
What is renal function like in a newborn?
Term newborn has GFR ~25% of an adult. Increase during 1st few weeks of life achieving adult levels ~2 years. Low concentration capacity counteracts with low GFR. Limited compensatory mechanism so become more sensitive to hypovolemia. Newborn kidney has more “holes” leading to a lower ability to concentrate urine and excrete larger molecules
What is the concentrating ability of a newborns kidney?
Term infant increase urine osm to 600-700mOsm/kg. Adults increase to 1,200 mOsm/kg. Free water clearance greater in infants than adults. ADH regulate osmolality of ECF
Which children are at a higher risk for dehydration?
Higher frequency of gastroenteritis (diarrhea and vomiting). Higher body surface area to volume ratio - leading to higher insensible losses. Inability to communicate and independently drink (infants/toddlers). Maturing renal compensatory pathways
What is Dehydration?
Intravascular fluid depletion (loss of plasma-free water disproportionate to loss of sodium) {common when ill child rehydrated w/ too little free water}
What is Volume Depletion?
Contraction of the total intravascular plasma pool {most common in pediatrics d/t increase insensible losses}
What are the most common signs of a child being dehydrated?
Irritable. Dry mucous membranes. No tears. Slowed capillary refill. Decreased turgor. Rapid/weak HR. Sunken anterior fontanelle
What is Isonatremia?
130-150
What is Hyponatremia?
< 130
What is Hypernatremia?
> 150
What happens to potassium during a deficit?
It will shift from ICF to ECF with free water shifts so may actually be depleted despite level wnl - wait to ENSURE VOIDING prior to replacement
How much fluid do you give for MAINTENANCE?
100ml/kg for first 10kg. 50ml/kg for next 10kg (11-20). 20ml/kg for each kg greater than 20
Whats a quick alternative way to figure out the maintenance fluids?
“4-2-1”. First 10kg = 4ml/kg/hr. Second 10kg = 2ml/kg/hr. Weight > 20kg = 1ml/kg/hr
What is done to treat mild/moderate dehydration?
Oral Rehydration Therapy (ORT). 10-20ml/kg to replace 1-2% loss over 6-8 hrs. Readily available (Pedialyte, Rehydralyte)
How much sodium is in “Normal Saline”?
154 mEq/L (0.9%)
What is found in Ringers Lactate?
Na, Cl, Ca, K, Lactate
How much fluid is in a NS Bolus?
10-20ml/kg NS over 1 hr
What is done for Acute Severe Hyponatremia?
Serum Na < 120, CNS symptoms. Administer 3% sodium chloride solution. 6ml/kg raises Na by ~5mEq/L
What is the daily Na requirement?
1-4 mEq/kg/day
What is the daily K requirement?
1-3 mEq/kg/day
What is typically given to infants < 10kg?
Typically D5-0.2% NaCl + 10mEq KCl/L
What is typically given to infants > 10kg?
D5-0.45% NaCl + 20mEq KCl/L
