Exam #2 Fluids and Electrolytes Flashcards
What are some differences between adults and children?
- Their fluid requirements
- Ability to manage fluids
- the smaller and younger we are, the more water and saline is in our body.
- Longer GI tract in relation to body size.
- Immature kidneys
- Higher metabolic rate due to increased respirations and HR
Immature immune system, results in more fevers and increases metabolic rate more
TNA is one of the most routine surgeries for children
Under general anesthesia
takes about 15 - 20 min
outpatient surgery
Normal for blood tinged vomit, as long as not bright red and excessive.
have to pee and drink before you go home
Adults and Adolescents are made up of _____% normal saline.
55%
Infants are made up of ____% normal saline.
75%
Little premies in the NICU are made up of _____% normal saline.
85%
The other important thing to remember is where the water is located.
Our fluid is located in the extracellular space and our intracellular space.
Extracellular fluid is
blood within the vessels
CSF
Synovial fluid ect….
any water that is outside of the cells
It is EASY to lose
Intracellular Fluid is
water that is inside of the cell.
It is protected by the cellular membrane.
It is harder to lose and tends to stay where it is supposed to stay.
ECF electrolyte
sodium – 135 – 145 mEq/L
and chloride
ICF electrolytes
potassium and magnesium –
K+ – 3.5 – 5.0 mEq/L
Mag – 1.5 – 2.2 mEq/L
How much of an infants body weight is ECF?
ECF 40%
By the time they reach adolescent age, they will have only 20% of their body weight as extracellular.
This is why infants lose fluid volume quicker because the majority of their fluid volume is ECF.
ECF is easier lost because it is NOT protected by the cell membrane.
How much of an infants body weight is ICF?
ICF 35%
It is important to remember which electrolytes compose the water because dehydration is directly related to where our sodium and chloride is.
true
Extracellular fluid has the sodium
Most of Intracellular fluid is mainly potassium
This does not mean that it does not pass the cell membrane.
What makes kids so special?
they are composed of more water
the smaller they are, the more water they are made up of
they have different vital signs, smaller they are the faster they breathe.
babies have immature kidneys
What are the 2 ways that we lose water?
sensibile water loss
Insensible water loss
What is sensible water loss?
peeing and pooping.
Things that can be measured
What is insensible water loss?
It is what we lose through skin and respirations.
How much insensible water loss occurs through the skin?
2/3
How much insensible water loss occurs through respirations?
1/3
So for insensible water loss in a child that breathes faster than an adult…..they are going to lose more water.
also, there is more body surface area in smaller babies available compared to the amount of our weight the smaller the baby is.
This makes a huge difference in preterm babies.
They have a lot of skin compared to their core muscle and fat.
Where as if you get a big guy, they have less skin compared to their core muscle and fat.
We get more insensible water loss the smaller the baby is
true
The thing about babies and infants is they have premature kidneys.
This means that they are not as great at concentrating their urine as much as it needs to be concentrated.
They also pee more than bigger guys
Because of their fast heart rate and because they are growing so fast they have a higher metabolic rate.
This causes them to lose more water than adults.
Then we have GI tract, so in relationship to their body size, they have a longer GI tract, and it is faster.
so they tend to poop more than adults. Especially when they are infants.
The other thing to remember, especially with infants and the younger population, is that they have an immature immune system.
So they get sick more often,
they have fevers more
which increases metabolic rate and causes more fluid loss.
Things that cause water loss in an children and infants:
Could be multiple….
Higher skin surface area
More ECF
Longer GI Tract
Immature Kidneys
Immature Immune system (FEVERS)
Higher metabolic rate from increased RR and HR
So to maintain this hydration, this equality of intake and output, our body has a wonderful system that it produces.
When we get thirsty, it means that we have had a little bit of fall in our blood volume.
Which is a rise in blood osmolarity.
When there is a rise in our blood osmolarity…what happens next?
It stimulates the pituitary to produce ADH.
What does ADH do?
It makes us stop peeing and holds onto water.
If you have a rise in your blood osmolarity, and you get thirsty…
If you do not drink and become more dehydrated it will cause what?
A decrease in blood flow to the kidneys.
What happens when you have a decreased blood flow to your kidneys?
The kidneys will release renin
What is renin?
Renin is a type of hormone that produces angiotensin.
What is angiotensin?
Angiotensin is a vasoconstrictor.
Angiotensin also stimulates the release of Aldosterone.
What does aldosterone do?
Aldosterone holds onto sodium
So if you are holding onto sodium within your system, then by osmosis….you are going to pull in more water.
released from the adrenal cortex
Daily fluid calculations =
100ml
50ml
20ml
Hourly Fluid Calculations =
4ml
2ml
1ml
always check the maintenance rate so that kids don’t die.
remember that kids playing are too busy to stop and take a drink.
teach parents to make them stop and drink
So when you are talking to families about what the childs daily fluid requirements are,
we must remember that the smaller the kid, the greater amount of fluid they need.
If your patient isn’t moving, if they are just in the bed and they have IV fluids going but do not have an increased metabolic demand…..
they are fine…
That is called maintenance fluids.
If the patient has fever, vomiting, bleeding out or anything like that…..we have to give more than maintenance fluids….
when they have a fever, they have a higher metabolic rate…
so the maintenance rate has to be increased.
the rule is that for every 1 degree F the patients temperature rises….you have to add 7ml/kg/day to maintenance rate.
Fever increases insensible water loss by approximately 7ml/kg/24 hours for every 1 degree F rise in Temp above 37.2oC (99oF)
Children have a tendency to become more highly febrile than adults
What is the normal urine output for infants and toddlers?
2 - 3 ml/kg/hr
What is the normal urine output for Preschool up to young school age children?
1 – 2 ml/kg/hr
What is the normal urine output for School-age children and adolescents?
0.5 – 1 ml/kg/hr
The types of dehydration are directly related to what?
the plasma sodium concentration because Na is the major osmotic force that controls fluid movement
What are the 3 types of dehydration?
Isonatremic – Isotonic
Hyponatremic – Hypotonic
Hypernatremic – Hypertonic
What is the most common type of dehydration?
Isotonic dehydration tends to be the one that is the most common.
Isotonic dehydration =
when you lose an equal amount of salt and water.
In isotonic dehydration the plasma sodium is going to be normal – 130 – 150 mEq/l
What is the most common cause of isotonic dehydration?
the most common cause in babies is diarrhea.
other causes:
vomiting
losing blood
hypovolemia is usually isotonic
major loss comes from ECF
When a kid has isotonic dehydration, what are you worried about them developing?
Shock
Hypotonic Dehydration =
Is when we lose more sodium than we have lost water.
Plasma sodium is less than 130 mEq/l
The loss of sodium is greater than the loss of water.
Water goes from ECF into the ICF – creates a greater proportional loss in ECF
Physical signs are more severe with smaller volume loss
What are the causes of hypotonic dehydration?
When you have diarrhea and someone did not use the proper replacement fluids.
If you replace with just water, it will cause hypotonic dehydration and water intoxication because you have not replaced the sodium
Inappropriate IV therapy
Syndrome of Inappropriate Antidiuretic Hormone (SIADH)
Unreplaced gastric suction
What is the most dangerous form of dehydration?
Hypertonic Dehydration
May result in permanent brain damage.
Hypertonic Dehydration occurs when…?
we have elevated sodium because we have lost more water than sodium.
Plasma sodium is greater than 150 mEq/l
This causes fluid shifts from the ICF to the ECF.
When you have hypertonic dehydration, and the fluid shifts from ICF to ECF…What is the most common Intracellular fluid to lose?
Brain Cells
This is why you start to develop CNS s/s
Since Hypertonic Dehydration is the most dangerous type of dehydration because it may result in brain damage….What are the S/S of brain damage?
CNS signs and damage:
alteration in LOC, poor ability to focus, lethargy, hyperreflexia, hyperirritability, seizures
What are the causes of Hypertonic Dehydration?
Over concentrated formula
High protein NG tube feeds that place an excessive solute load on the kidneys
Requires special fluid therapy
What is the treatment for Hypertonic dehydration?
The treatment for hypertonic dehydration is very important to remember…
Replace deficit gradually over 48 hours and avoid rapid fall in serum sodium
Rapid administration of fluids will cause rapid shift of fluid into the dehydrated brain cells leading to cerebral edema
So when we look at dehydration, we look at how we are going to treat the patient..
This is based on not only the type of dehydration (iso/hypo/hyper), but we are also going to look at how bad they are dehydrated.
(Mild, moderate, severe)
What are the S/S of mild Dehydration?
3-5% weight loss
Thirsty
Normal Pulse
Normal Respirations
Irritable and Fussy
Alert
UOP Mildly decreased
Cap Refill greater than 2 sec
Mucus membranes normal/sticky
tears present
anterior fontanel normal
What are the S/s of Moderate Dehydration?
6-10% weight loss
Moderate thirst
slight increase in pulse
slight tachypnea
lethargic but arousable
Sunken fontanels, eyes
Decreased UOP 1.020 - 1.030
Cap refill 2-4 sec
Dry mucous membranes
tears decreased
anterior fontanel normal/sunken
What are the signs and symptoms of Severe Dehydration?
10% weight loss
intense thirst
tachycardic with weak thready pulse
rapid deep respiratory rate
not arousable, grey, clammy
marked sunken fontanels/ eyes
NO UOP - Spec/grav > 1.030
Cap refill greater than 4 sec
Skin tenting/ mottled
parched mucous membranes
absent tears
anterior fontanel sunken
Kids that have severe dehydration do not have volume so they have decreased
cardiac output
When we are in the ED, Best reliable physical assessment signs of degree of dehydration are:
prolonged capillary refill
Abnormal skin turgor
abnormal respiratory pattern
What is the earliest sign of dehydration?
Earliest detectable sign of dehydration is tachycardia
Tachycardia is NOT the most reliable sign
How do we treat mild dehydration?
Mild dehydration:
Usually managed at home
Oral rehydration solution
50 ml/kg over 4 – 6 hours
Work with small sips if reluctant to take the fluid
Or Pedialyte popcicles
Continue breastfeeding/age appropriate diet
Oral rehydration solution (ORS) 10mL/kg with every stool or emesis
When teaching the family how to manage dehydration at home…dont just tell them to use oral rehydration solution 50ml/kg over 4-6 hours…
Show them how much it is in a cup. Multiply it out and measure it for them.
Provide them with a medicine cup for toddlers. Because toddlers do not want to see a big cup of stuff they have to drink when they do not feel good.
teach them that the child needs to continue eating. Never make NPO.
Oral rehydration solution also has to be used if they are having vomiting and diarrhea.
Every time they poop they need an extra 10ml. This is additional to the maintenance doses.
This is to replace losses.
What is the treatment of moderate dehydration?
Home or Emergency Room until rehydrated
Oral rehydration solution
100 ml/kg over 4 – 6 hours
Continue breastfeeding
Age appropriate diet when hydration status has improved
In moderate dehydration, the child can only go home if they are willing to drink.
the child has to drink 100ml/kg over 4-6 hours
If they can do this, they will be watched for a few hours in the ED and sent home
If you have a toddler that is in the “NO” stage and will not drink because he feels bad…
you have to rehydrate with IV.
How do we treat severe dehydration?
Hospital
Parenteral rehydration:
Use Isotonic solutions – 0.9% Sodium Chloride or lactated Ringers
20ml/kg over 20 minutes – reassess and repeat if necessary
If the child is severely dehydrated, remember they will be lethargic….they will not even care that you are in the room.
You immediately start an IV
and give bolus of normal saline @ 20ml/kg over 20 minutes
When the bolus is done, listen to their lungs to make sure they are handling the fluids.
reassess:
are they still lethargic
cap refill
If all still not normal, give another bolus and repeat process until the kid is screaming at you and ready to leave. because that is better LOC
At this point, you can start completing their fluid replacement (maintenance plus catch up, and continuing losses)
Recalculate maintenance fluids every _____ hours.
8
never 24 with kids
Now when you have diarrhea you are losing a lot of ______.
potassium
We cannot EVER replace potassium unless the child is peeing well.
The rule of the game is that the child has to have a normal urinary output before they can be given potassium in their fluids.
this is to avoid hyperkalemia
must calculate normal urine output for their age.
Severe dehydration – 3 phases
- Boluses – until child responds
- Maintenance rate + catch up + ongoing losses. Calculated for 8 hours
- Patient begins to take oral fluids. K+ is added to IV fluids when kidney function returns to normal
Rate of rehydration
Rehydration occurs over 24 hour period in isotonic or in hypotonic dehydration.
Rehydration of hypertonic dehydration occurs over 48hours
Oral rehydration –
If the child is alert, awake, and not in immediate danger of severe dehydration the oral rehydration management is treatment of choice
Parenteral rehydration:
Use Isotonic solutions – 0.9% Sodium Chloride or lactated Ringers
20ml/kg over 20 minutes – reassess and repeat if necessary
D5 ½ NS at 2 X the hourly maintenance rate (second phase after rescue)
What is the most common cause of dehydration in children?
diarrhea
This is a big cause of child deaths around the world so we must know how to manage it.
20% of all deaths in developing countries are related to diarrhea and dehydration
Diarrhea Definition:
3 or more stools that take the shape of their container in a 24 hour period.
just because it is loose doesn’t mean it is diarrhea.
Diarrhea can be infectious…
variety of causative organisms – parasitic, viral, bacterial – called gastroenteritis
What is the most common cause of acute diarrhea?
rotovirus
This is why we have an immunization for it now.
True or False
If a child comes in with rotovirus, they still are required to finish their immunizations for rotovirus.
True
They are still at risk for contracting it again.
most common in young children and infants (most severe in 3 – 24mo)
What are the bacterial causes of acute diarrhea?
Salmonella and Shigella;
Clostridium difficile
What is a parasite that is responsible for acute diarrhea?
Giardia – parasite – most common in daycares
If you suspect an outbreak in a daycare, you must report it to the heath department.
What are the new guidelines for C Diff?
Stop all antimicrobial agents
Metronidazole (Flagyl) the drug of choice
Contact isolation
Soap & water
Is it possible to become a carrier of C Diff?
yes
How do we treat acute diarrhea?
Rehydrate the child
Continue breastfeeding or lactose-free formula in infants
Continue regular diet with older children
Continue replacing stool loss with 10ml/kg ( 4 – 8 oz.) of ORS for every diarrheal stool
True or False
NEVER give antidiarrheal medication to a child with diarrhea.
True
Whatever is causing the diarrhea needs to get out.
Don’ts for treating diarrhea…
Don’t give antidiarrheal meds
No BRAT diet- not enough protein
clear liquids alone
No cokes/caffeine (diuretic)
No Gellatin
To much sugar can cause more dehydration
Fluids with high carbohydrate content, low electrolyte content, and high osmolality
Sodas, fruit juice, gelatin, broth
Foods to help with diarrhea.
Rice Wheat Potatoes Cereal Yogurt Cooked vegetables Lean Meat
Preferred Dietary Management for diarrhea
Continued feeding or early reintroduction of a normal diet has no adverse effects and actually lessens the severity and duration of the illness and improves weight gain compared with the gradual reintroduction of foods
Continue breast-feedings with ORS to replace ongoing stool loss
Formula-feeding resumed
May need lactose-free formula for a few days
Older children resume regular diet, including milk, after rehydration
Prevention of Diarrhea
Most diarrhea is spread by the fecal-oral route
Teach personal hygiene
Clean water supply/protect from contamination
Careful food preparation
Hand washing
Rehydration during vomiting
Vomiting precedes abdominal pain in gastroenteritis
5 ml ORS every 5 minutes
Oral administration of ondansetron (Zofran)
Popsicles of Oral Rehydration Solution
What are the S/s of Water Intoxication?
elevated urinary output HA, vomiting, seizures, irritability, sleepiness
What are the causes of water intoxication?
Inappropriate IV therapy
Tap water enemas
Incorrectly mixed formula
Excess water ingestion
Too rapid dialysis
Too rapid reduction of glucose levels in diabetic ketoacidosis
What are the types of shock?
Hypovolemic
Cardiogenic
Distributive shock
Obstructive
What are the 3 stages of shock?
Compensated
Decompensated
Irreversible
Determined by:
Degree of tachycardia and perfusion to extremities
Level of Consciousness
BP
Early signs of shock
Mild tachycardia Apprehension Irritability Pallor Diminished urinary output Thirst Narrowing pulse pressure Normal blood pressure
Developing decompensation
Pronounced tachycardia Tachypnea Developing metabolic acidosis Oliguria Cool, pale extremities Poor capillary refill Decreased responsiveness Narrowed pulse pressure BP normal
Irreversible Shock
Hypotension
Lethargy or coma
Anuria
Definition of Hypotension
Systolic BP of < 70 in Infants
Systolic BP of < 70 + (age in years x 2) in children 1 – 10 years
Systolic BP < 90 in children over 10 years
Treatment of Shock
Airway – O2
Fluid resucitation
Vasopressor
Positioning: child flat with legs raised above level of heart
Keep child warm
Hypovolemic Shock
Reduction in circulating blood volume
Related to blood loss
Plasma losses/burns
Extracellular fluid losses
-Diarrhea
-Dehydration
Hypovolemic Shock Nonhemorrhagic
20 ml/kg of Normal Saline or Lactated Ringer’s , repeating as needed
Hypovolemic Shock Hemorrhagic
Control external bleeding
20ml/kg NS/LR bolus, repeat 2 or 3 times as needed
Transfuse with PRBC’s as indicated
