Ch 14: Fluid and Electrolytes Quiz Flashcards Preview

Med Surg I > Ch 14: Fluid and Electrolytes Quiz > Flashcards

Flashcards in Ch 14: Fluid and Electrolytes Quiz Deck (59):
1

Osmosis

movement of water across semi-permeable membrane from low solute concentration to high solute concentration.

2

Osmolality

# of particles of solute in a unit of fluid based on weight (blood, urine)

3

Osmolarity

# of particles of solute in a unit of fluid based on volume. (Spec. gravity)

4

Tonicity

ability of solutes to cause an osmotic driving force and promote water movement from one compartment to another.

5

Adrenal gland

releases aldosterone in response to decreased Na+, or increased K+ or renin.

6

Parathyroid

regulates calcium and phosphate. Secretes PTH which causes bone resorption, calcium absorption from intestines, calcium reabsorption from renal tubules.

7

Renin-Angiotensin-Aldosterone System

*Renin = enzyme that converts angiotensinogen into angiotensin I. (liver)
*Renin is released by the juxtaglomerular cells of kidneys in response to decreased renal perfusion
*ACE converts angiotensin I to angiotensin II
*Vasoconstriction increases arterial perfusion pressure and stimulates thirst.
*Sympathetic nervous system stimulates release of aldosterone in response to increase renin
*Aldosterone regulates volume

8

Atrial Natriuretic Peptide (ANP)

opposite of renin-angiotensin-aldosterone system

9

Gerontologic considerations for increased risk of F&E disorders

*decreased renal and pulmonary function
*altered ratio of body fluid to muscle mass
*Altered response to F&E changes
*Atypical
*Rapid onset
*Changes in acid-base balance

10

Gerontologic Assessment Considerations

-Thirst mechanism
-NPO risk
-Test preps
-Cardiac, kidney, lung, adrenal function
-Attention to intake/output and DAILY WEIGHTS
-Medication effects

11

Fluid gains/losses

Gain: PO, IV, SQ, Enteral
Loss: Kidneys: 1500mL/day - urine
**normal u/o = 1 ml/kg/day
Insensible loss:
*Skin 600 mL/day
*Lungs 400 mL/day
* GI tract 100-200 mL/day

12

S/S of hypovolemia

-weight loss
-thirst, dry mucous membranes
-poor skin turgor
-Decreased LOC
-HR, orthostatic hypotension
-Hemoconcentration, increased urine spec. grav., decreased u/o.
-flat jugular veins, time for veins to fill

13

Causes of hypovolemia

-decreased intake
-blood loss/ hemorrhage
-GI: V/D/ GI suction
-Renal: diuretics, Addison's, diabetes insipidus, osmotic diuresis
-3rd space shift: decreased oncotic pressure
-Ascites

14

The nurse would best assess the adequacy of fluid volume replacement in a patient with hypovolemia by monitoring:

Vital signs and daily weights

15

S/S of hypervolemia

-rapid weight gain
-Ascites, decreased serum proteins
-Decreased serum and ua osmolality
-decreased urine Na+
-Dyspnea
-HTN, edema, JVD, time for veins to empty

16

Causes of hypervolemia

-excess fluid intake
-excess Na+ intake
-increased retention of sodium & water
-renal failure
-SIADH (increased ADH)
-heart failure
-liver failure
-decreased serum proteins
-liver failure
-malnutrition
-burns
-nephrotic syndrome

17

Normal Sodium levels

135-145 mEq/L

18

Functions of Sodium

-#1 ECF cation
-Major determinant of ECF osmolality
-Muscle contraction/nerve impulse transmission
-Controls water distribution

19

Hyponatremia

Sodium less than 135
Severe = less than 120

20

Causes of hyponatremia

-Na+ deficit
-net gain of water (w/o salt)
**Causes of Na+ deficit
-decreased intake
-increased loss
*diuretics
*GI suction
*Excess sweating
-decreased aldosterone

21

S/S of hyponatremia

s/s dependent on:
rate of fall
duration of low Na+ levels
ECF volume

-GI: anorexia, N/V, cramping
-Neuro: h/a, lethargy, confusion, seizures caused by H2O moving into brain cell
-Low serum and urine osmolality

22

Hypernatremia

sodium level greater than 145

23

Causes of hypernatremia

-decreased fluid intake
-hypertonic tube feeding without adequate water
-increased water losses
-increased insensible losses
-diabetes insipidus (decreased ADH)
-Increased sodium
-increased aldosterone
-corticosteroids
-excess sodium bicarb. or sodium chloride

24

S/S of hypernatremia

-thirst
-dry mucous membranes
-elevated temp, flushed skin
-change of LOC
-seizures
-3rd spacing: edema
-hypotension
-increased deep tendon reflexes
-increased serum and urine osmolality

25

Potassium

Normal values 3.5-5.5 mEq/L

26

Function of potassium

-#1 intracellular cation
-active transport I Na+-K+ pump
-muscle contraction
-nerve impulse transmission
-acid/base blanace

Regulated by:
kidneys
aldosterone

27

Hypokalemia

potassium (K+) less than 3.5

28

Causes of hypokalemia

decreased intake
IV fluids w/o K+
Increased losses
-GI
-diuresis (thiazides)
-increased aldosterone
-K+ shifting from ECF to ICF
-alkalosis
-insulin excess

29

S/S of hypokalemia

-anorexia, N/V
-ileus
-muscle weakness or cramps
-paresthesia
-digoxin toxicity
-dysrhythmias: PVCs, V-tach

30

Hypokalemia memory jogger

S - skeletal muscle weakness
U - u wave (ECG change)
C - constipation
T - toxic effects of digoxin
I - irregular, weak pulse
O - orthostatic hypotension
N - numbness (paresthesia)

31

Hyperkalemia

K+ greater than 5.5

32

Causes of hyperkalemia

-increased intake
-decreased loss
-renal failure
-decreased aldosterone
-K+ shifting from ICF to ECF
-hemolysis
-burns
-crushing injury
-chemotherapy
-acidosis
-insulin deficiency

33

S/S hyperkalemia

-N/V/D
-abdominal cramps
-muscle weakness
- decreased reflexes
-paresthesias
-paralysis
-acidosis: decreased pH
-insulin deficit: increased glucose
-EKG: peaked t waves, prolonged PR interval, Wide QRS, V-tach

34

Calcium

Normal levels are 8.5 - 10.5
-plasma proteins affect level
Has an inverse relationship with phosphorus

35

Causes of hypocalcemia

-decreased intake
-decreased absorption
-laxative abuse
-diarrhea
-malabsorption
-decreased vit d
-decreased PTH
-increased phosphorus
-increased losses
-diuresis
-pancreatitis
-decreased albumin
-alkalosis
-blood transfusion

36

S/S of hypocalcemia

-paresthesia
-tetany
-Chovostek's sign
-Trousseau's sign
-increased deep tendon reflexes
-seizures
-laryngeal stridor
-irritability
-anxiety
-impaired clotting
-alkalosis

37

Chvostek's sign

An indicator of hypocalcemia. It is a twitch of the facial muscles following gentle tapping over the facial nerve in front of the ear that indicates hyperirritability of the facial nerve.

38

Trousseau's Sign

An indication of latent tetany in which carpal spasm occurs when the upper arm is compressed by a bp cuff or the like for 3 minutes. An indicator of hypocalcemia.

39

Hypercalcemia

Calcium greater than 10.5

40

Causes of hyeprcalcemia

increased calcium resorption from bones
increased calcium absorption from gut
decreased calcium excretion by kidneys (most common)
Acidosis
Decreased PO4

41

S/S of hypercalcemia

-Anorexia, N/V
-abdominal pain, cramping
-Ileus
-constipation
-confusion
-decreased LOC from lethargy to coma
-decreased reflexes
-hypertension
-bone pain
-risk of digoxin toxicity
-increased u/o with thirst
-decreased PO4
-EKG: short QT interval

42

Magnesium

Normal levels 1.5-2.5 mg/dL
-competes with calcium for GI absorption

43

Functions of magnesium

nerve/muscle function
allows heart and vascular relaxation
protects heart from ischemia
metabolic processes
needed for absorption and utilization of K+
Regulated by GI absorption and kidneys.

44

Hypomagnesemia

Mg+ less than 1.5 mg/dL

45

Causes of hypomagnesemia

decreased intake
decreased GI absorption
increased GI losses
increased renal losses

46

S/S of hypomagnesemia

muscle weakness, twitching, tremors, tetany
dysphagia
altered LOC: confusion, hallucinations, seizures
Increased reflexes
Chovostek's sign
Trousseau's sign
Common to have low K+ and Ca++ concurrently
EKG changes: prolonged QT, wide QRS, V-tach

47

Hypomagnesemia memory jogger

Seizures
Tetany
Anorexia, arrhythmias
Rapid heart rate
Vomiting
Emotional lability
Deep tendon reflexes increased

48

Hypermagnesemia

Mg+ greater than 2.5 mg/dL

49

Causes of hypermagnesemia

renal failure
increased intake (pills)

50

S/S of hypermagnesemia

weakness
decreased reflexes
decreased LOC: confusion, lethargy, coma
Resp. depression > 15
N/V
decreased b/p, decreased HR

51

Muscular twitching & hyperirritability of the nervous system indicate tetany. The nurse would identify these as symptoms (sx) of which electrolyte imbalance?

Low calcium level

52

Phosphorus

Normal level is 2.5 - 4.5
-functions: ATP energy production, nerve/muscle activity, promotes release of oxygen from Hgb
-regulated by kidneys (primary), PTH, vit d

53

Hypophosphatemia

Phos less than 2.5 mg/dL

54

Causes of hypophosphatemia

decreased intake/absorption
increased losses
increased phosphate utilization

55

S/S of hypophosphatemia

altered LOC: lethargy irritability, apprehension, confusion
Muscle weakness: respiratory, cardiac
Ileus
***belly surgery, reintroduction of food = increased risk for hypophosphatemia.***

56

Hyperphosphatemia

Phos greater than 4.5 mg/dL

57

Causes of hyperphosphatemia

decreased excretion
increased intake
phosphate shifting from ICF to ECF

58

S/S of hyperphosphatemia

Dry, itchy skin
s/s of hypocalcemia from Ca++ binding with PO4-

59

Chloride

Normal levels = 96-106
Function: regulates acid/base balance by combining with other ions
Imbalances associated with sodium and/or acid/base imbalances.