Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Therapeutics I > Block 4: Na+ and Fluids > Flashcards

Block 4: Na+ and Fluids Flashcards

1
Q

What is osmolality?

A

number of solute particles in 1 kg of solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the normal osmolality?

A

275-295 mOsm/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is tonicity?

A

Osmotic pressure → determine fluid flow between 2 solution with depend on the relative concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is oncotic pressure?

A

Exerted by the solute in the blood plasm → force that pulls water into vasculature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is hydrostatic pressure?

A

Pressure generated by the water on the walls of the capillary → forcing water out the vasculature space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are crystalloids?

A

Small molecules of the solute to expand the volume in the vasculature (electrolytes, NS, LR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are colloids?

A

Large molecules of the solute to expand the volume in the vasculature (proteins, RBC)

Big molecules can not cross the membrane into 3rd space, but water can

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What components maintain oncotic pressure?

A
  1. RBC
  2. Albumin
  3. Electrolyte
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why do we use colloidal infusions?

A

increase the intravascular volume and not intracellular or interstitial volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the types of colloidal solutions?

A
  1. Albumin
  2. Dextrans
  3. Etherified starch
  4. Gelatin
  5. Mannitol
  6. Blood transfusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What happens if you administer hypertonic solution?

A

↑ ECF and ↓ ICF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What happens if you administer isotonic solution?

A
  1. ↑ ECF not affecting ICF
  2. Solution stay in intravascular space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens if you administer hypotonic solution?

A
  1. ↑ ECF and ICF
  2. Partial solution in intravascular and partial goes in cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is TBW?

A

60% body weight for men; 55% for women

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the ICF solutes?

A

Potassium, magnesium ions, Proteins, organic phosphates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is ECF solutes?

A

Sodium, chloride, bicard, plasma proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the homeostasis?

A

Intra- and extra-cellular osmolarity are equal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How do you calculate daily fluid requirements?

A

First 10 kg = 100 ml/kg, next 10 kg = 50 ml/kg, 20 ml/kg remainder

30-35mL/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the what components play into compartment shifting?

A
  1. Solutes create osmotic gradients
  2. Water moves rapidly across cell membranes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What causes dehydration?

A
  1. Increased losses due to fever, sweating, diarrhea)
  2. Reduced intake
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What causes volume excess?

A
  1. Reduced losses (CHF, cirrhosis, renal failure)
  2. Excess intake
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the dehydration assessment?

A
  1. Decreased skin turgor
  2. BUN/sCr >20
  3. UOP <0.5 mL/kg/hr
  4. Dry mucous membranes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do we treat dehydration?

A
  1. Replace lost fluid and electrolytes
  2. Oral replacement (pedialyte)
  3. Sever needs IV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is edema?

A

↑ in interstitial fluid volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the causes of edema?

A
  1. Increased capillary hydrostatic pressure
  2. Increased capillary permeability
  3. Decreased colloid osmotic pressure
  4. Obstruction in lymphatic system
  5. Excess body water and sodium
  6. Combo of mechanisms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How do you assess edema?

A
  1. Pulmonary edema
  2. Anasarca
  3. Wheezing/crackles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the treatment for edema?

A
  1. Diuretic (if currently on diuretics, ↑ the dose or add different MOA of diuretic)
  2. Sodium restriction (1-2 g/day)
  3. Treat underlying cause
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How do loops work?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How is loop resistance built?

A
  1. Continuos infusion
  2. ↑ frequency
  3. Add thiazide - one hr prior to loop
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the clinical uses of loops?

A
  1. Edema
  2. Acute renal failure (improve UO and limit kidney damage)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the ADRs of loops?

A

Hypoeletrolytes
Metabolic alkalosis
Hyperuricemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Why are loops considered first line for loop diuretics?

A

Most potent
Ceiling dose
Rapid acting, short duration (except torsemide)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

How do thiazide differ from loops?

A

Longer half-life vs loops, but weaker

Less frequent dosing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the clinical uses of thiazide?

A

Mild edema, kidney stones due to hypercalciuria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the ADR of thiazide?

A
  1. Hypokalemia
  2. Hypovolemia
  3. Hypercalcemia
  4. Hyponatremia
  5. Hypomagnesemia
  6. Hyperuricemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What thiazide is IV and PO?

A

Chlorothiazide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the MOA of K sparing diuretics and how the drugs differ?

A

Inhibit ENaC channel in DCT and collecting duct

  1. Direct inhibition by triamtere and amiloride
  2. Aldosterone interference by spironolactone and eplerenone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

How do K sparing differ from loops and thiazides?

A

Weaker with gradual fluid loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Clinical uses of K sparing?

A
  1. HTN
  2. Adjust in CHF
  3. Combine with loops or thiazides to counteract K+ loss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

ADR of K sparing?

A
  1. Metabolic acidosis
  2. Hyperkalemia
  3. Synecomastia with spiranolactone
41
Q

Where does Acetazolimide work?

A

Proximal acting diuretic

42
Q

Indication for Carbonic anhydrase inhibitor?

A

Acid/base disorders and glaucoma

43
Q

What are the ADRs of CAIs?

A

Metabolic acidosis, hypokalemia

44
Q

What is the treatment of cirrhosis using diuretics?

45
Q

What is the treatment for nephrotic syndrome?

46
Q

What is the diuretic components of CHF treatment?

47
Q

What is Na+ regulated by?

A
  1. Renal mechanism
  2. NP
  3. RAAS
48
Q

What is H2O regulated by?

A
  1. ADH/AVP
  2. Sodium concentration
  3. Effects osmolarity
49
Q

What is the normal Na level?

A

136-145 mEq/L

50
Q

How do calculate serum osmolality?

A

Osms = (2 x serum Na) + (serum glucose/18) + (BUN/2.8)

51
Q

Where is AVP/ADH synthesized?

A

Synthesized in hypothalamus and secreted by posterior pituitary

52
Q

What is the difference between dehydration and hypovolemia?

A

Dehydration: loss of total body water leads to increased serum osmolarity
Hypovolemia: symptomatic deficit in ECF volume not referred to osmolarity or tonicity

53
Q

What is hyponatremia?

A

serum Na < 135 mEq/L

An excess of extracellular water due to impaired water secretion
1. AVP release
2. SIADH from cancer, injury

54
Q

What causes AVP release?

A

CHF, nephrotic syndrome, cirrhosis

55
Q

What are the risk factors of hyponatremia?

A

Disease related: CHF, cirrhosis, CKD
Polydipsia
Diet: Tea and toast diet

56
Q

What are the drugs that induce hyponatremia?

A

Thiazides, hypotonic fluids, SSRIs, carbamazepine, lamotrigine, haloperidol

57
Q

Are the signs and symptoms of hyponatremia?

A

Stupor/coma
Anorexia
Lethargy
Tendon Reflexes
Limp muscles
Orthostatic hypotension
Seizures/HA
Stomach cramping

58
Q

What is the difference between acute and chronic hyponatremia?

A

Acute: onset within 48 hours; risk of cerebral edema

Chronic: onset >48 hours; risk of osmotic demyelination

59
Q

What hypertonic hyponatremia? Treatment?

A

Osm >300 due to hyperglycemia, mannitol, glycine

Correct Sodium for hyperglycemia

60
Q

How do you correct sodium?

A

Sodium decreases by 2.4 mEq/L for every 100 mg/dL increase in glucose >100

Corrected Na = measured Na + [2.4(glucose-100)/100]

61
Q

What is isotonic hyponatremia?

A

Factitious/Pseudo-hyponatremia:
Hyperlipidemia: TG >1000
Hyperproteinemia

62
Q

What is hypotonic hyponatremia?

A

Osm <280 (true hyponatremia)

Evaluate urine studies and volume status for diagnosis

63
Q

What are the causes of SIADH?

A
  1. TUmor
  2. CNS disorders
  3. Pulmonary disroder
64
Q

What are the drugs that causes SIADH?

A
  1. SSRI
  2. TCD
  3. MOAI
  4. Antiseizure
  5. Vasopressin (Desmopressin)
65
Q

How is the algorithm for hyponatremia treatment?

66
Q

How do you treat hypotonic hypervolemic hyponatremia?

A

1st line: Fluid and sodium restriction (1-1.5 L fluid per day, <2 g Na per day)
2nd: loop diuretics
3rd: Vaptans
Last: Demeclocycline

Severe sx: 3% NaCl

67
Q

How do you treat hypotonic hypovolemic hyponatremia?

A

1st line: isotonic fluid administration

Need to replace sodium AND water

Preferred: Oral fluids/electrolytes

0.9% NaCl IV or LR IV

Severe sx: 3% NaCl

68
Q

How do you treat hypotonic euvolemic hyponatremia?

A

1st: Address underlying cause (d/c drugs inducing)
2nd: Fluid restriction (1-1.5 L/day)
3rd line: Isotonic saline + loop
4th line: Vaptans
Last: Demeclocycline

Severe sx: 3% NaCl

69
Q

How do you administer 3% saline?

A

Administer 150 mL over 20 min and repeat until Na+ increases by 5 mEq/L

70
Q

What are vaptans used to treat?

A

Inhibits AVP (ADH)

Used in hypervolemic or euvolemic hyponatremia

Reserved for symptomatic or sever hyponatremia

71
Q

What are the types of vaptans?

A

Conlvaptan
Tolvaptan

72
Q

What is the difference between the vaptans?

A

Conivaptan: IV
Tolvaptan: PO, therapy should begin inpatient

73
Q

What is the MOA of demeclocycline?

A

Tetracycline Antibiotic that inhibits tubular AVP activity → free water excretion

74
Q

What is the onset and CI of demeclocycline? Indication?

A

3-6 days

Avoid in children, pregnant women, liver disease

Chronic SIADH as last resort

75
Q

What is true hyponatremia?

76
Q

How do you treat hyponatremia based on tonicity?

77
Q

What is the General Rules to Prevent Overcorrecting of Sodium?

A

Acute onset or severe symptoms require more aggressive therapy: 3% NS

Chronic should be corrected more slowly

78
Q

What is the max Na+ that prevents overcorrection?

A

Acute: 12mEq/L/day
Chronic: 6-8 mEq/L/day

Results in cerebral edema, seizure, osmotic demyelination, death

79
Q

How do you calculate total deficit of Na based the patient?

80
Q

What do you evaluate in hyponatremia treatments?

A
  1. Water restriction (stable: ≥125)
  2. VRA (monitor serum Na Q4)
  3. Evaluate lung congestion, ascites, peripheral edema daily
  4. Signs/Symptoms of hyponatremia
  5. Follow up and assess 1 week of discharge
81
Q

What are the signs and sx of hypernatremia?

82
Q

What are the causes of hypernatremia?

A
  1. Diabetes Insipidus
  2. Excess losses: GI, renal, insensible
  3. Dehydration
  4. Diabetes Insipidus
  5. Burns
  6. Limited water access
83
Q

How do you calculate ECF deficit?

A

ECF (water) deficit = TBW(current) x [1-140/Nas)

84
Q

Compare the types of hypernatremia?

85
Q

What is the goal of treating DI and hypernatremia?

A

Goal: Decrease UOP to <2 L/day

86
Q

What the cause of central DI? Tx?

A
  1. decreased AVP secretion
  2. Familial

Desmopressin 10-20 mcg nasally QD or 10-20 mg PO QD

87
Q

What are drugs that cause nephrogenic DI?

88
Q

What are the tx for nephrogenic DI?

A
  1. Correct underlying cause
  2. Hypotonic IV fluids
  3. Sodium restriction + HCTZ 25 mg PO QD-BID
89
Q

What are the labs associated with DI?

A

up > 3 L/day
Usom < 250 mOsm/kg

90
Q

How do you diagnose DI?

A
  1. Desmopressin test dose 4mcg SQ or IV
  2. Measure urine osmolality before and after dose
  3. UOsm will increase to ~600 mOsm/kg in central DI
91
Q

How do you assess hypovolemia hypernatremia?

A

Uvol < 3 L/day, Uosm > 450 mOsm/kg

TX : 200-300 ml/hr NS -> intravascular volume restore -> _ NS or D5W

92
Q

How do you assess euvolemia hypernatremia?

A

Uvol > 3 L/day, Usom < 250 mOsm/kg

→ Diabetes Insipidus (DI)

93
Q

How do you assess DI central hypernatremia?

A

Central DI - CNS insult and no offensive drug
Response to desmopressin
TX: Desmopressin

94
Q

How do you assess DI nephrogenic hypernatremia?

A

Not responsive to desmopressin and offensive drugs (lithium)

TX: HCTZ, water replacement + Na restriction

95
Q

How do you assess hypervolemia hypernatremia?

A

Furosemide 20-40 mg IV Q6h if not currently on furosemide

96
Q

What is the infusion rate to correct hypernatremia?

97
Q

What components are you looking at for stable Na levels?

Therapeutics I (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions