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Flashcards in Fluids- electrolytes Deck (60)
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1

Components of body fluid?

- ICF: 2/3 of total body fluid
-ECF: 1/3
ISF, plasma, and lymphatic fluid

2

Electrolytes in ECF and ICF?

- ECF: Na+ (142 mEq/L), Cl- (103 mEq/L), HCO3-
- ICF: K+ (140 mEq/L), Mg, phosphates

3

Water movement regulation?

- starling forces: hydrostatic pressures and osmotic pressures:
Capillary hydrostatic pressure: pressure in capillary pushing fluid out
Interstial fluid hydrostatic pressure: pushing fluid in from ISF
- Osmotic force due to plasma concentration (drawing fluid into capillaries)
- Osmotic force due to ISF protein concentration (drawing fluid out)

4

What is osmolality? What is most important factor?

- concentration of an osmotic soln when measured in osmols of solvent
plasma: 280-295 mOsm/kg
- Na+ is most impt plasma osmolality factor (water follows Na+)

5

Process of fluid and electrolyte replacement? IV solutions?

- assess ins and outs
- oral replacement preferred when tx dehydration
- IV:
saline equivalents: crystalloids - normal saline or LR
water equivalents: D5W
if 3% NS - have to do central line (will destroy peripheral veins)

6

What are the components of LRs?

- 250-273 mOsm/L
- Na+, Cl-, lactate, Ca+, K+

7

Parenteral colloids?

isotonic
- albumin: 290-31- mOsm/L
- blood products:
packed RBCs, fresh frozen plasma

8

Saline: 3%, 5%, D5W1/2NS adverse effects?

- ICF depletion
- fluid overload
- hypernatremia
- hyperchloremia

9

Albumin adverse effects?

- allergic reactions
- possible infection transmission (hepatitis)

10

Impt steps in assessing types of fluid loss?

- pt hx
- sxs
- vital signs and PE

11

What is hypervolemia?

- too much Na+
- expansion of effective arterial blood volume
- CHF, cirrhosis, aldosterone, renal disease

12

WHat is hypovolemia?

- too little Na+
- volume contraction
- dehydration: V/D, exercise, not drinking enough water

13

What is hyponatremia? Hypernatremia? Edema?

hyponatremia:
- too much water
- not enough Na+

hypernatremia:
- too little water (dehydration)
- excess Na+

edema: too much Na+ with water retention in the ISF (abdomen, lungs) - alcoholics, cirrhosis, metastatic cancers

14

Severity of edema?

- 1+ = 2 mm
- 2+ = 4 mm
- 3+ = 6 mm
- 4+ = 8 mm

15

How to tx mild dehydration?

- oral replacement:
fluids with electrolytes are preferred
- avoid fluids with high sugar concentration
- water and sports drink or in children pediolyte
- stop activities that create ongoing losses

16

Assessing degree of fluid loss for moderate hypovolemia?

- hx: any GI losses (V/D), excessive exercise, renal losses
- sx: easy fatiguability, thirst, muscle cramps, postural dizziness, abdominal pain, CP, lethargy, confusion, decreased urination
- clinical manifestations: decreased skin turgor, tachycardia, dry mucus membranes

17

How do electrolyte imbalances present? How do these imbalances occur?

- sxs: precipitate as CV, neuro, and neuromuscular abnormalities
- disruptions occur: via drugs, disease states, diarrhea, vomiting, infection, hormone imbalances, malignancies
- to tx these: need results of lab tests then start IV fluids

18

Etiologies of hyponatremia?

- hypovolemia: GI losses: vomiting, and diarrhea, dehydratioon
renal losses: (thiazide diuretics), ACEIs, mineralocorticoid deficiency
- normovolemia: SIADH, primary polydipsia/marathon runners, low dietary solute intake, psychogenic polydipsia
- hypervolemia: CHF, cirrhosis, nephrotic syndrome, advanced syndrome (rare)
- others: hypothyroidism, primary adrenal insufficiency, drugs

19

What lab values do you want to know for hyponatremia? lab value indications?

hyponatremia is less than 135 meq/L
- serum osmolality impt
- urine Na+
- assess severity:
less or equal to 120 meq/L panic value***
- 120-130: depends on sxs and situations
- greater than 130 is generally not tx

20

Clinical manifestations of chronic hyponatremia?

- cerebral adaption:
going to have fatigue, nausea, dizziness, confusion, lethargy, muscle cramps, gait disturbances and forgetfulness

21

Clinical manifestations of acute hyponatremia?

- acute hyponatremic encephalopathy: cerebral over hydration related to degree of hyponatremia
fatigue an malaise are usually the first sxs
- HA, lethargy, coma, seizures and eventually respiratory arrest
- acute hyponatremic encephalopathy may cause permanent neuro damage or death
- can be hyponatremic classified by ECF status: hypovolemic: GI losses, renal losses (thiazides), normovolemic: SIADH, low Na+ intake, hypervolemic: CHF, cirrhosis

22

How does osmotic demyelination happen?

- try to correct hyponatremia and then you overcorrect making ECF hypernatremic so H2O leaves brain too quickly and it shrinks

23

How can acute hypotonic hyponatremia occur? WHat are the sxs?

- can result in sxs of neuronal cell expansion and cerebral edema
- Nausea/HA, seizure, coma and death

24

Hyponatremia etiologies with inability to suppress ADH problem?

- true volume depletion (GI or renal losses - thiazide diuretics), decreased tissue perfusion (reduced CO or systemic vasodilation in cirrhosis for instance)
syndrome of inappropriate ADH secretion (SIADH)

25

Causes of hyponatremia with appropriate suppression of ADH secretion?

- primary polydipsia
- low dietary solute intake
- advanced renal failure

26

Causes of hypovolemic hyponatremia?

- GI or renal losses
- if serum Na+ hasn't dropped critically low quickly
- usually just volume replacement orally or IV if more severe

27

Tx for hypovolemic hyponatremia?

- NS/isotonic saline
- depending on pt status may do slow bolus
- then maintenance depending on ongoing losses

28

Causes of hypervolemic hyponatremia?

- CHF, cirrhosis, renal failure

29

Tx of hypervolemic hyponatremia?

- restrict fluids: 1000-1200 ml/day
- restrict sodium: 1000-1200 mg/day
- utilize loop diuretics to remove excess fluid, K+ replacement

30

What is SIADH? Causes? Tx?

- too much ADH. Either Eu/hypervolemic hypotonic hyponatremic presentation

can be:
drug induced: carbamazepine, SSRIs, haloperidol, and thorazine

disease induced: malignancies, CNS disorders, post-surgery, pulmonary infections

Tx: tx underlying cause, fluid restriction is mainstay!!!!! May use oral salt tablets, loop diuretics