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107 terms

1245 Fluid & electrolytes

What are the three general functions of Fluids & Electrolytes?
- transport nutrients, gases and waste

- essential for cellular functions

- move shape, form and cushion the body
What is OSMOSIS?
- movement of WATER from an area of MORE WATER to an area of LESS WATER
- there would be less water if a solution has a greater concentration of particles
movement of SOLUTES from an area of GREATER concentration to an area of LESSER concentration
requires ENERGY to move molecules from an area of LESSER concentration to an area of GREATER concentration

- uses ATP / ex: Na/K pump
passage of FLUID from HIGH to LOW pressure areas because of HYDROSTATIC PRESSURE differences on both sides of the membrane

- arteriole = ↑ pressure inside vessel so fluid moves to interstitial space
- venule = ↓ pressure inside vessel so fluid moves from interstitial space to vessel
- measures concentration of particles in a solution or it's pulling power
- concentration of a solution per Liter
- compares to plasma (is it greater or lesser)

- how full of particles is the intervascular space
what is osmolality
concentration of a solution expressed per kg
What is normal plasma osmolarity level?
270-300 mOsm/L
a high serum osmolarity indicates?
a low serum osmolarity indicates?
What does changing the osmolarity cause?
fluid shift between the blood vessels and the cells
what is an ISOTONIC solution?
- 275-295 mOsm/L
- most common;
- about the same osmolarity as plasma
- given mostly when pt. is dry / particles need fluid

0.9 NS "normal saline" (Sodium based)
RL (Ringers Lactate) = isotonic with blood
D5W (Glucose based)
What is an HYPERTONIC solution?
- > 295 mOsm/L
- greater concentration (more particles) than plasma
- pulls fluid out of interstitial space into vascular space (from rest of body into blood stream)
- give when we need to take fluid away from interstitial space (ex: edema)

D5 0.9NS
D5 0.45NS
D10 W
What is an HYPOTONIC solution?
- < 275 mOsm/L
- lesser concentration/particles than plasma
- shifts from the bloodstream to the rest of the body/interstitial space
- give if pt. is very dehydrated and several lab results say so
- ex: Water is a hypotonic solution

0.45 NaCl (half NS)
0.33 NaCl (1/3 NS)
what are the four mechanisms that maintain fluid balance & how do they function?
1. kidneys = selectively retain or eliminate electrolytes & output of dilute urine with FVE
2. ADH = causes kidneys to retain H2O
3. Aldosterone = causes vasoconstriction, Na & H2O retention
4. Thirst = usually won't dehydrate if they have thirst mechanism & have access to fluids. Immobility would cause a problem
How do the kidneys maintain fluid balance?
• selectively retain or eliminate electrolyte
• output of dilute urine with FVE
What is the function of Aldosterone?
causes vasoconstriction, Na & H2O retention, secretion of K, ↑ BP. It increases blood volume
What are 2 types of FVD?
1.) Hypovolemia

2.) Third spacing
What are 2 types of FVE?
1.) Hypervolemia

2.) Edema (excessive fluid shift to the interstitial space)
- aka FVD
- loss of H2O & solutes from ECF
- weight loss occurs
- skin tenting
- decreased blood plasma
- fluid deficit, low on volume
- fluid shifts/moves to potential (interstitial) space causing edema
- because of the shift there will be lower intravascular circulating volume
- may see weight gain

- ex: trauma or illness
Assessment (non-lab) findings in FVD (8)
- dry mouth/mucous membranes (MAJOR)
- ⬇ turgor (MAJOR)
- ⬆ HR (3RD SPACING) - due to ⬇circulating volume, the heart pumps faster
- Hypotension (marked/orthostatic) - due to ⬇ circulating volume (3RD SPACING)
- Mental Status changes
- ⬇ capillary refill
- cool pale skin
- weak pulses
What are six lab findings in FVD?
- ↑ BUN (creatinine normal)
- ↑ Hct if H2O loss (b/c ↓ volume, Hct is a %)
- ↓ hgb/Hct if bleeding
- ↓ urine output (kidneys regulate fluid, so hold fluid)
- concentrated urine (dark yellow/brown) *** concentrated b/c vascular particles are concentrated, due to ⬇ H2O)
- urine specific gravity > 1.025 (normal=1.003-1.030)
What is a nursing diagnosis for FVD?
Deficient fluid volume related to losses secondary diarrhea AEB:
Dry skin and mucous membranes
3 pound weight loss in 24 hours
What are six FVD Interventions?
- identify & treat cause
- **daily weight=most accurate indicator of fluid status (1-2lbs overnight = fluid)
- Fluid replacement → (iso/hypo/IV/albumin/blood) * Isotonic is used unless lab values prove imbalance
- monitor patient → VS, pulses , LOC
- I&O = 30mL/hour, 240mL/shift (watch for S/S of fluid overload → fluid in lungs=crackles)
- skin & mucous membrane care
What is fluid volume excess (2)?
1. Hypervolemia = high volume, excessive retention of H2O & solutes
2. edema = excessive fluid shift to interstitial space
Assessment (non lab) findings in FVE (6)
- edema (dependent=pitting/pulmonary=crackles/ anasarca=generalized)***
- taught, shiny skin (puffy looking)***
- rapid bounding pulse
- ↑ BP (b/c increased volume in intravascular)
- distended veins
- weight gain
What are six lab findings in FVE?
- ↓ BUN (unless renal failure)
- ↓ Hct (b/c ↑ volume & Hct is a %)
- CXR = pulmonary congestion
- SOB; dyspnea (crackles)
- ↓ pO2
- may have respiratory problems if really bad
What is a nursing diagnosis for FVE?
Excess fluid volume related to venous and arterial abnormalities secondary to immobility AEB:
3+ pitting edema of lower extremities
What are the five FVE Interventions?
- diagnose & treat the cause
- reduce fluids (fluid & Na restriction/diuretics (especially in extreme cases/ hemodialysis) Ex. Order 1200mL/daily → dietary & nursing split the amount
- monitor → VS, pulses, I&O, resp status & edema
- **daily weight checks**
- skin care (esp. if edema b/c more prone to skin breakdown)
What are normal Sodium (Na⁺) levels?
135-145 mEq/L
What are the three Roles of SODIUM & what major change would you see with a Na imbalance?
- fluid volume regulation
- generates & transmits nerve impulses
- supports neurologic function

What is hyponatremia
⬇ Na or ⬆ H2O in ECF so fluid moves, by osmosis, from ECF to ICF
What are HYPONATREMIA assessment findings, including lab diagnostics?
- lethargy, headache, ↓ LOC, confusion
- muscle weakness, cramps, tremors
- abdominal cramps & nausea
- If HYPOVOLEMIA ➔ rapid thready pulse, low BP, cold, clammy skin
- If HYPERVOLEMIA ➔ edema, HTN, rapid bounding pulse
- Na <135
- ↓ lower specific gravity (unless hypo/isovolemia b/c getting rid of a lot of fluid & Na goes with it)
What are two nursing diagnoses & related outcomes for hyponatremia?
1. RC: Hyponatremia
Outcome: Pt. will maintain normal serum sodium by end of shift AEB Na 135-145

2. Risk for falls related to lack of awareness of environmental hazards secondary to confusion from hyponatremia.
Outcome: Pt. will be free from injury by end of shift AEB: No falls
What are seven hyponatremia interventions?
• Fluids → No free H2O, because if you put more hypotonic fluids into ECF it would move into cells & worsen the already existing hyponatremia. (Gatorade is okay) & IVF=Isotonic (volume replacement)
• NaCl tablets
• High Na foods (canned soups, cheese, ketchup, processed meats, salty snacks)
• Hypertonic solution = in controlled situations (Ex. ICU) if really low & see neuro signs, but you want a slow change (don't want too much to come out of cells)
• Monitor → VS, LOC, I&O, Weight (daily), & lab serum
• Safety (altered LOC)
• Teaching
What is hypernatremia
• ⬆ Na or ⬇ H2O (water loss/dehydration) in ECF so fluid moves, by osmosis, from ICF to ECF. The water loss is more than the sodium loss.
• ECF is hypertonic (high Na concentration) so fluid moves out of the cells & into the ECF
What are the Causes of HYPERNATREMIA?
• Water loss-more water lost than sodium
* causes: fever, heat stroke, pulmonary infections, burns, diarrhea, diabetes insipidus, lack of fluid consumption, problems w/thirst, insensible H2O loss

• Excessive sodium intake
*causes: NaCl tabs, IVF (usually hospitals fault)
HYPERNATREMIA assessment findings
- restlessness, agitation→ lethargy, confusion, coma
- dry mucous membranes
- dry flushed skin b/c ⬇fluids
- low-grade temp
- thirst
- nausea & vomiting
- urine output ⬇ b/c fluid loss, so kidney preserve

- Na > 145
- ↑ specific gravity, greater concentration of Na (except diabetes insipidus=head injury & they don't have ADH so they get rid of water →which is ↑ dilute urine)
- serum osmo greater than 300 mOsm/kg
What are two diagnoses & outcomes for hypernatremia?
RC: Hypernatremia
Outcome: Pt. will maintain normal serum sodium by end of shift AEB: Na 135-145

Risk for fall related to faulty judgment secondary to hypernatremia
Outcome: Pt. will be free from injury by end of shift AEB: No falls
What are nine HYPERNATREMIA interventions?
- salt free foods
- sodium restriction
- diuretics and water (free water)
- vasopressin (if DI) so they can hang onto water
- Isotonic (unless really bad then hypotonic)
- monitor patient = VS, LOC, I&O, labs, wt.
- oral hygiene
- safety
- teaching
What are the three Roles of POTASSIUM & what major change would you see with a K imbalance?
- Assist in skeletal & heart muscle contraction
- Aid in transmission of nerve pulses
- Affect acid base balances

What are the four causes of HYPOKALEMIA?
- not enough intake
- too much output (urine/GI= N&V, diarrhea)
- drugs (lasix, steroids)
- hyperglycemia
Can have s/s even w/a level of 3.7 mEq/L
*** slight changes have profound effects
HYPOKALEMIA assessment findings
- **weak irregular pulse, **palpitations, orthostatic hypotension

- leg weakness, cramps, paresthesias, fatigue, apathy, **resp weakness** = assess first b/c muscle weakness has caused decreased respirations


- K < 3.5 (<2.5 is severe)
- ↓ Mg
- ECG changes (pt has extra beats or complains of palpations)
What are two nursing diagnoses & related outcomes for hypokalemia?
RC: Hypokalemia
Outcome: Pt. will maintain normal serum potassium by end of shift AEB: K = 3.5-5

Risk for decreased cardiac output related to irregular heart rhythm
Outcome: Pt. will have adequate cardiac output by end of shift AEB: Regular heart rhythm & No c/o dizziness or palpations
What are some HYPOKALEMIA Interventions?
- replace potassium w/ high K foods (dried fruits, nuts, meats, veggies, fruits)
- oral supplements
- IV replacement (can be irritating to veins)
*** max 10mEq/hr
*** replace Mg 1st (it helps hold onto K)
- monitor pt. VS, HR & RHYTHM, labs, dig level, I&O
- teaching
Five cautions when replacing POTASSIUM
- irritating to GI track & vein
- burns vein/dilute or slow down
- use heat on IV site
- Mg has to be replaced 1st
- Max is 10 mEq/hr for IV
What are seven causes of HYPERKALEMIA?
*** most dangerous of electrolyte disorders
- too much intake
- too little output
- drugs (ACE, aldactone, KCl, NSAIDS)
- tissue injury=cell damage & K is released
- renal failure
- blood transfusions
- hypoaldosteronism (secretion of K has ⬇)
* if K is too high, the heart will stop
What are HYPERKALEMIA assessment findings?
- ↓ HR, IRREGULAR PULSE (slowing down of pulse), hypotension

- paresthesias, muscle weakness, paralysis, legs→resp muscles

- abdominal cramping / diarrhea
- nausea

K >5 (severe > 7). K>5 gets treated
ECG changes
What are two nursing diagnoses & related outcomes for hyperkalemia?
RC: Hyperkalemia
Outcome: Pt. will maintain normal serum potassium by end of shift AEB: K = 3.5-5

Risk for decreased cardiac output related irregular heart rhythm
Outcome: Pt. will have adequate cardiac output by end of shift AEB: Regular heart rhythm & No c/o dizziness
What are some HYPERKALEMIA Interventions?
- restrict K
- eliminate K from the body = ** loop diuretic (lasix), dialysis, sodium polystyrene, sulfonate (Kayexalate)=binds to K & eliminates in stool
- Shift K into cells (NaHCO3 / Dextrose & Insulin)
- Administer CaCl or Ca gluconate
- Monitor pt. VS, EKG, I&O, dig level (b/c ↑ K levels, labs
- Safety
- Teaching
What are the five Roles of Magnesium & what major change would you see with a Mg imbalance?
- Important for cell metabolism
- Influences cardiac contractility
- Maintains electrical activity in nerves & muscles
- Influences Ca levels through effect of PTH
- Cellular activity (impulse transmission) & regulates integrity of cell membrane. balance across CM

What are six causes of HYPOMAGNESEMIA?
- poor intake/absorption
- increased loss from GI or urinary tract
- Hypercalcemia
- SIADH (syndrome of inappropriate antidiuretic hormone hypersecretion)
- sepsis
- serious burns
What are some HYPOMAGNESEMIA assessment findings?
- change in LOC
- **hyperactive reflexes **
-* seizure*

- Cardiac IRRITABILITY (bradycardia, hypotension)
- decreased GI motility
- S/S ↓ K or ↓ Ca

Mg < 1.3
may see ↓ K or ↓ Ca
ECG changes
What are two nursing diagnoses & related outcomes for hypomagnesemia?
RC: Hypomagnesemia
Outcome: Pt. will maintain normal serum magnesium by end of shift AEB: Mg = 1.3-2.1

Risk for aspiration related to reduced level of consciousness secondary to hypomagnesemia
Outcome: Pt. will not aspirate by end of shift AEB:
Lungs remain clear & Oxygen saturation greater than 92%
what are six HYPOMAGNESEMIA interventions?
- replace Mg
- Oral
- IV MgSO4
- Monitor pt. VS, LOC, dysphagia, reflexes, I&O
- Safety
- teaching: high Mg foods (chocolate, nuts, meats, green leafy veggies) Why is it chronically low?
What are two HYPERMAGNESEMIA causes & relating factors?
- excess intake
- decreased excretion from renal dysfunction

* Uncommon
* Usually pt. only has if we give it to them = too much supplement
* can be high & not see S/S
What are six HYPERMAGNESEMIA assessment findings?
- flushing, warmth, weakness
- decreased reflexes
- generalized weakness progressing to paralysis

- ↓ BP

Mg > 2.5 mEq/dL
ECG changes
What is a nursing diagnoses & related outcomes for hypermagnesemia?
RC: Hypermagnesemia
Outcome: Pt. will maintain normal serum magnesium by end of shift AEB: Mg = 1.3-2.1
What are five HYPERMAGNESEMIA Interventions?
- Increased elimination (fluids=goes into intravascular & dilutes/loop diuretics)
- Block effects (Ca gluconate)
- Monitor pt. VS, LOC, I&O, labs, ECG
- monitor **REFLEXES**
- teaching = avoid Mg

* If it's hyper we can give fluids to dilute it out
What are the four Roles of Calcium & what major change would you see with a Ca imbalance?
- provides structure to bones & teeth
- Maintains cell membrane structure & impulse transmission
- Affects muscle contraction
- Required for blood to clot

What are nine causes of HYPOCALCEMIA
- not enough intake
- **Vitamin D deficiency
- too much loss
- malabsorption from GI tract
- loop diuretics
- burned or diseased tissues
- low Mg, high phosphorus
- blood transfusions>3. blood contain citrate which binds to Ca
- PTH secretion is reduced or eliminated (thyroid surgery/parathyroid surgery, injury, disease)
What are 13 possible HYPOCALCEMIA assessment findings?
- paresthesias-circumoral (burning, tingling)
- twitching, tremors, muscle cramps
- hyperactive DTR's
- Chvostek's (face)
- Trousseau's (arm/BP)

- cardiac arrhythmias
- laryngeal spasm
- may see hypokalemia also
- numbness & tingling around lips

serum Ca < 8.5
ionized Ca < 4.5
ECG changes
- ↑ Phosphorus (inversely proportional to Ca)
What are some HYPOCALCEMIA interventions?
- Calcium Chloride (fast w/ 3x more calcium)
- Calcium Gluconate (slower/more commonly used)
- Mg replacement
- Vitamin D supplements (helps w/absorption)
- Reduce phosphate (Aluminum hydroxide antacids)
- monitor pt VS, resp stridor, ECG, labs, Chvostek's & Trousseau's
- Safety
- teaching (Ca foods & exercise =↑ Ca levels thru bone development & absorption)
What are five causes of HYPERCALCEMIA?
- hyperparathyroidism
- cancer (causes bone breakdown/fractures)
- low phosphate (inversely proportional to Ca)
- antacid abuse (that contain calcium)
- excessive vitamin D & A
What are eight HYPERCALCEMIA assessment findings?
- Neuromuscular weakness
- cardiac dysrhythmias
- decreased GI motility
- renal (polyuria & stones)

total Ca > 10.5
ionized > 5.1

ECG changes
X-ray - pathological fractures
What are seven HYPERCALCEMIA interventions?
- increase calcium excretion (hydration=isotonic, diuretics, hemodialysis)
- block bone reabsorption and ↓ GI intake (steroids/phosphates)
- monitor pt VS, LOC, ECG, I&O, labs
- safety
- strain urine
- ambulate (helps bone)
- teaching

* if we ↑ phosphate we will ↓ calcium
What are the three Roles of Phosphorus?
- nerve & muscle function
- works w/ Ca for bone structure
- WBC phagocytosis & platelet function
What are the two causes of HYPOPHOSPHATEMIA?
- malnutrition
- malabsorption
What are four HYPOPHOSPHATEMIA assessment findings?
- weakness
- confusion
- S/S hypercalcemia (b/c inversely proportional

PO4 < 2.5 mEq/L
What are five HYPOPHOSPHATEMIA interventions?
- increase intake
- oral/IV supplements
- pt safety
- teaching
- monitoring= s/s of hypercalcemia
What are three causes of HYPERPHOSPHATEMIA?
- increased intake
- decreased excretion
- cell destruction
What are two HYPERPHOSPHATEMIA assessment findings?
- calcifications
- S/S hypocalcemia
What are six HYPERPHOSPHATEMIA interventions?
- fluids
- diuretics
- dialysis
- pt. safety
- monitoring
- usually oral supplements
usually more concerned with Ca portion vs. PO4
What are the two roles of CHLORIDE?
- travels with Na to maintain serum osmolarity
- secreted by gastric mucosa (HCl) for digestion
What are the four causes of HYPOCHLOREMIA?
- salt restriction
- IV fluids
- GI drainage
- drugs
What are three HYPOCHLOREMIA assessment findings?
- hyperactive reflexes
- S/S hypokalemia
- slow, shallow respirations
What are three HYPOCHLOREMIA inventions?
- Cl replacement (salty broth, KCl)
- restrict water
- pt. safety / monitoring
* mostly concerned with acid-base balance
What are four causes of HYPERCHLOREMIA?
- dehydration
- hypernatremia
- renal failure
- drugs (kayexlate)
What are two HYPERCHLOREMIA assessment findings?
- S/S metabolic acidosis (tachypnea, kussmaul respirations)

- S/S hypernatremia
What are three HYPERCHLOREMIA interventions?
- restrict Na, Cl
- increase fluids
- pt. safety / monitoring

* be careful because most IV solutions contain NaCl
Excessive output (urine or GI) results in low ____
___, ___, & ___ imbalances frequently occur together
Hyperglycemia & steroids lower ___
Renal failure raises ___ and ___
K and PO4
Cell damage raises ___ and ___
K and Mg
b/c they are intracellular cations
Blood transfusions elevate ___ and lower ___
elevate - K
lower - Ca
Diarrhea lowers ___
Cancer metastasis (bone metastasis) increases ___
Calcium is inversely proportional to ___
Calcium is proportional to ___ & ___
K & Mg
The major symptoms of these electrolytes (Na, K, Mg, Ca) are?
Na - mental status
K - cardiac & muscles
Mg - reflexes & muscles
Ca - Chvostek & Trousseau, bone changes
Normal Potassium (K⁺) levels
3.5-5 mEq/L
Normal Calcium (Ca⁺⁺) levels
total 8.5 - 10.5 mg/dL
ionized 4-6 mg/dL
Normal Magnesium (Mg⁺) levels
1.3-2.1 mEq/L
Normal Chloride (Cl⁻) levels
95-105 mEq/L
Normal Phosphorus (PO4⁻) levels
2.5-4.5 mEq/L
Hydrostatic pressure
- capillary blood pressure
- atriole end

- force of the weight of water molecules pressing against the confining walls of a space
Colloid osmotic pressure
- venule end

- form of pressure exerted by proteins in blood plasma that usually tend to pull water into the circulatory system

- the osmotic or pulling force of albumin
(albumin is a water magnet)
What are the four elements of extracellular electrolytes?
Na, Cl, Ca, PO4
Cl = major anion
Na = major cation
What are the three elements of intracellular electrolytes?
K, Mg, PO4
- cellular damage and these get released
K = major cation
PO4 = major anion
What is TPN?
- Total Parenteral Nutrition

- composed of dextrose, proteins and electrolytes in an IV

- it can supply most of the nutrients the body needs

- is frequently ordered when bowel functioning is inadequate or bowel rest is required
- D5W (5% dextrose in water); don't use in excess volumes because it doesn't contain any sodium, can cause hyponatremia or death

- 0.9% NaCl (normal saline); not good for routine because it only provide Na & Cl in excessive amounts, good for circulatory insufficiently & diabetic ketoacidosis

- RL (Lactose Ringers); contains multiple electrolytes sames as plasma, good for hypervolemia, burns, fluid loss, & mild metabolic acidosis
0.33% NaCl (1/3 strength saline); provides Na, Cl & free water, allows kidneys to select & retain needed amounts

0.45% NaCl (1/2 strength saline); provides Na, Cl, & free water, used to treat hypernatremia
D5 0.45NS (55 dextrose in 0.45% NaCl); common, used to treat hypovolemia, used to maintain fluid intake

D5 0.9NS ( 5% dextrose in 0.9% NaCl); replaces nutrients & electrolytes, can temporarily treat hypovolemia

D10W (10% dextrose in water); used for peripheral parenteral nutrition (PPN)

what is hydrostatic pressure?
It is the water (hydro) molecules in a confined space pressing against the confining walls. it the force that pushes water outward from a confined space through a membrane.
If you see tachycardia & hypotension it is a sign of?
low circulating volume/low fluids