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946: Nutrition
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297
Pharmacology
Professional
02/29/2012

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Term
Total body water is about __ - __ % of total body weight
Definition
45-65%
Term
Body water for children and men
Definition
0.6 x body weight
Term
Body water for women over 70 y/o
Definition
0.45 x body weight
Term
Body water for women and old men (>70 y/o)
Definition
0.5 x body weight
Term
intracellular versus extracellular fluid
Definition
2/3 intercellular and 1/3 body water is extracellular
Term
Extracellular fluid: how much is interstitial vs. intravascular
Definition
3/4 interstitial fluid
1/4 intravascular fluid
Term
Major cation or ECF
Definition
Na (Ca, K, Mg)
Term
Major anion of ECF
Definition
Cl (HCO3, PO4, SO4, organic acids, proteins-albumin)
Term
Major cation or ICF
Definition
K+ (Na, Mg)
Term
Major anion of ICF
Definition
PO4 (SO4, HCO3, organic acids)
Term
Osmolarity vs. Osmolality
Definition
Osmolarity: (osmoles/L of soln)

Osmolality: osmoles/kg of solvent

**For water 1 kg = 1 L so osmolarity and osmolality are used interchangably for WATER ONLY
Term
oncotic pressure
Definition
colloid osmotic pressure caused by plasma proteins
Term
crystalloid vs colloid
Definition
Crystalloid-fluid made up of water and dissolved SALTS or SMALL SUGARS

Colloid- a homogeneous 'solution' of LARGE MOLECULES such as albumin or dextran
Term
Ions that make up 90% of ECF osmolality
Definition
Na, Cl, Bicarbonate
Term
Ions that make up most of ICF osmolality
Definition
K, Mg, PO4
Term
Normal Sodium levels
Definition
135-145 mEq/L
Term
Normal Calcium levels
Definition
8.5-10.5 mg/dL
***Ionized Ca: 4.4-5.4 mg/dL
Term
Normal phosphate levels
Definition
2.5-4.5 mg/dL
Term
Normal potassium levels
Definition
3.5-5 mEq/L
Term
Normal magnesium levels
Definition
1.7-2.3 mg/dL

NOTE: poor indicator of true Mg in body
Term
Normal Serum Osmolality Equation and what it tells us
Definition
(2 x SNa) + (BG/18) + (BUN/2.8) = 275-290 mOsm/kg
1. serum sodium is major contributor
2. even though glucose (and BUN) count for less in terms of osmolality, if they get significantly high (ex: BG=1200) then will start to play a more significant role and will become a concern
Term
Clinical Presentation of Dehydration
Definition
Increased heart rate (body senses lower Volume and tries to compensate)
Decreased BP
Lower PCWP (pulmonary capillary weight pressure) or CVP (central venous pressure)
Low urine output
Hypernatremia
Increased serum osmolality
Shock
Term
CVP
Definition
central venous pressure
Term
PCWP
Definition
pulmonary capillary weight pressure
Term
Assessment tools for dehydration
Definition
weight changes
thirst
mucous membranes
tear production
jugular vein visibility when supine
capillary refill time
urine specific gravity (measures concentration of urine)
skin turgor
physical symptoms (ex: BP, HR)
orthostasis (loss of 10-15% ECF)
Term
Ideal rate of change of serum osmoles in dehydration treatment
Definition
~2 mOsm/hour
Term
what is ringers lactate
Definition
isotonic fluid that contains sodium (thus it will mainly stay in ECF) but also has other ions
Term
a BUN/Scr ratio >20 indicates _________
Definition
dehydration
Term
urine Na of __________ indicates renal etiology of hyponatremia
Definition
over 20 (the kidney is NOT compensating for losses)
Term
Where will 1 liter of 1/2NS distribute?
-how much in ECF
-how much in ICF
-how much in intravascular vs. interstitial
Definition
500 ml NS and 500 ml plain water

500 ml NS only in ECF (375 interstitial/125 IV)

500 ml pure water distributes evenly (~333 mL ICF/~167 ml ECF [~40 ml IV/127 ml interstitial)

TOTAL:
333 mL ICF
667 mL ECF
500 mL interstitial
167 mL IV
Term
How does D20W distribute?
Definition
distributes evenly (the amount of dextrose doesnt matter because will eventually get metabolized and distribute evenly), however it is hypertonic so must just be careful where it can be infused
Term
Is D5NS hypo-, iso-, or hypertonic?
Definition
Hyper (D5W gets metabolized, left with NS but initially dextrose too)
Term
Why is tonicity important?
Definition
it indicates where it is safe to infuse something--ex: peripheral versus central line (once it is in the body, the body water will adjust to create an isotonic environment)
Term
General treatment of dehydration.
Definition
1. immediate vascular expansion--500 ml IV for adults if symptomatic
2. Correction of fluid and electrolyte deficits
-restore balance over 24 hours+ if possible
3. Maintenance of fluids and electrolytes
Term
If patient in shock with massive blood loss--what should you give them?
Definition
1. blood
2. other replacement fluids
Term
LR
Definition
Lactated Ringers
Term
Examples of Hypertonic Solutions
Definition
TPN
D10W
3% NaCl
Term
Examples of Isotonic Solutions
Definition
NS
Lactated Ringer's
5% Dextrose 0.225% NaCl
Term
Examples of Hypotonic Solutions
Definition
0.45% NaCl
Term
Does D5W = Free water?
Definition
NO! Even though D5W is sodium free, it is isotonic for infusion and thus doesnt cause cell swelling
Term
What would happen if you infused sterile water?
Definition
Hemolysis-->fatal
Term
What are the end products of dextrose metabolism
Definition
water and carbon dioxide
Term
Maintenance Volume Fluid Calculations for Adults/Adolescents
Definition
for weight >20 kg

1500 mL + 20 ml(weight-20kg)
Term
Maintenance Volume Fluid Calculations for Peds
Definition
for weight 10-20 kg

1000 mL + 50 mL(weight-10kg)
Term
Maintenance Volume Fluid Calculations for Neonates
Definition
for weight <10 kg

100 mL/kg
Term
Drugs that can affect fluid dosing in dehydration
Definition
diuretics
steroids
ACE inhibitors
Lithium (kidney sees it the same as Na+)
Vasoactive agents
Term
Examples of colloids
Definition
Albumin 5% or 25%
Dextran 40 (10% soln)
Dextran 70 (6% soln)
Hetastarch
Term
Theory that colloids should be given if have low blood volume (in dehydration)--is this seen to be true?
Definition
NO, studies show there is no real success--about the same effectiveness as crystalloids
Term
Endogenous Albumin Info
Definition
12-14g/day produced
contributes to oncotic pressure
normal concentration: 3.5-5 g/dL
non-tissue bound albumin from interstitial fluid will return to intravascular space via LYMPHATIC DRAINAGE
tissue bound albumin is metabolized
Term
typical albumin concentration
Definition
3.5-5 g/dl
Term
uses of dextran
Definition
prevent thromboembolism
improve peripheral blood flow
Term
1 gm of albumin will bind ____ mL water
Definition
~18 mL water
Term
how long will albumin stay in the intravascular space?
Definition
16 hours
Term
what will happen when 100 mL of albumin 25% is administered?
Definition
all stays in intravascular space and each gram (25 g total) is associated with 18 mL water. so 450 mL increase in water in intravascular space (100 mL from infusion + 350 mL from interstitial space)
Term
what will happen when 500 mL of albumin 5% is administered?
Definition
5 g/100 ml = 25 g total which is associated with a volume of 450 mL (so increase of 450-500 ml in intravascular volume)

pretty much what gets infused with 5% albumin is the increase in volume in the IV space
Term
With edema, should you give albumin 5% or 25%?
Definition
Albumin 25%

THEN give a diuretic to get rid of the fluid that has been pulled into IV space
Term
uses of exogenous albumin
Definition
resuscitation
correction of edema
Term
ADRs of exogenous albumin
Definition
pulmonary edema
decreased calcium (Ca binds to albumin)
anaphylaxis (because it is a protein)
$$$
Term
What affects the "dwell time" and duration of expansion of the intravascular space with dextran?
Definition
particle size of the dextran
Term
how much water is associated with 1 gram of dextran?
Definition
20-30 mL water is associated with 1 gram of dextran
Term
if add 500 ml D40 what will be the change in volume?
Definition
increase of 100-1500 mL (10% soln where 1 gram is associated with 20-30 mL water) at 2 hours
Term
ADRs of Dextran
Definition
renal failure
anaphylaxis (b/c protein)
osmotic diuresis (stop i SpGr >1.03 and Urine Volume<0.5mL/kg/hr)
false increase in blood glucose, total protein, and bilirubin
interference with blood cross matching
bleeding (keep doses <1.5g/kg/d)
RES blockade-immune function effect (reticuloendotheial blockade)

**NOTE: dont occur with crystalloids
Term
What is hetastarch
Definition
6% soln in NS

Dosed at 20 mL/kg/day
Term
ADR of Hetastarch
Definition
Coagulopathy-dose dependent
depressed platelet count
prolonged PT and PTT
Pulmonary edema
Anaphylaxis (rare)
Hyperamylasemia: no alteration in pancreatic function but levels 2x normal for up to 5 days
Term
What is the primary ion of the plasma
Definition
Na
Term
Normal plasma osmolarity

How is it derived?
Definition
280-295 mOsm/kg water

(2 x [Na]) + ([glucose]/18) + (BUN/2.8)
Term
Main functions of sodium
Definition
1. maintain ECF volume
2. Blood pressure regulation
3. maintain osmotic equilibrium
Term
what constitutes Hyponatremia
Definition
<135 mEq/L
Term
what level indicates hypernatremia
Definition
>150 mEq/L
Term
what is the daily intake required for sodium
Definition
~50-100 mEq/d (RDI<2.3g = <100mEq)
Term
What two systems regulate Na
Definition
ADH (aka arginine vasopressin)

Renin-Angiotensin-aldosterone system (RAAS)
Term
What is the most common electrolyte problem in hospitalized patients
Definition
hyponatremia (15-30% of cases)
Term
Hyponatremia is an INDEPENDENT risk factor for _____ (more than 1)
Definition
Death in...
1. geriatric
2. HF
3. Cirrhosis
4. ICU
...patients
Term
Is hyponatremia usually a water or sodium problem?
Definition
Water problem
Term
Mild Hyponatremia
Definition
125-130 mEq/L

Sx: impaired posture, attention, gait with chronic/increased fall risk
Term
Severity of hyponatremia depends on ________ and _________
Definition
rate and magnitude
Term
What is a BIG concern with hyponatremia (moderate/severe)
Definition
Osmotic demyelination syndrome
decreased plasma omolarity causes water to move into brain cells (swell/burst)

Na/K try to move out, but compensation takes 48 hours
Term
Moderate and severe hyponatremia levels and symptoms
Definition
Moderate: 115-125 mEq/L
Severe: 110-115 mEq/L

Hypo-osmolality induced volume expansion of brain cells-->altered MS, seizures, coma, permanent brain damage, death
Term
What causes hypertonic hyponatremia
Definition
having another molecule in the blood that usually isnt there:
1. mannitol
2. hyperglycemia
3. propylene glycol
4. polyethylene glycol
Term
T of F: the body will automatically decrease sodium in the blood with hyperglycemia
Definition
T: for every 100 mg/dl increase in blood glucose, the serum sodium decreases by 1.7 mEq/L (causes a 2 mOsm/kg decrease in osmolality)
Term
What is the difference between hypertonic and isotonic hyponatremia
Definition
with isotonic, the body has been able to compensate for the osmolality change due to solutes other than Na in the plasma (same causes for both-ex: mannitol, hyperglycemia...)
Term
Which type of hyponatremia is most common?
Definition
Hypotonic hypernatremia
Term
Hypovolemic hyponatremia
Definition
volume depletion and Na loss

can be caused by loss of Na renally or extrarenally

Tx: remove the cause and give NS
Term
T or F: in hypovolemic hypotonic hyponatremia you first lose sodium.
Definition
F: first you lose fluid (via sweating, diarrhea, thiazide diuretics)-->increase osmolality-->increase ADH-->water retention-->concentrate urine
Term
How long does it take for thiazide-induced hyponatremia to develop?
Definition
within 2 weeks
Term
MOA of thiazide diuretics
Definition
inhibit sodium-chloride carrier in DISTAL tubule

BLOCKS Na reabsorption-->which allows water and Na to be removed
Water then gets retained through ADH-->causes greater loss of Na than water
Term
Urine Na (< or >) 20 mEq/L when Na losses are extrarenal (ex: GI, skin)
Definition
LESS than because the kidney tries to reabsorb salt
Term
Which type of diuretic infrequently causes hyponatremia?
Definition
Loop (because works further down)
Term
When Na > 20 mEq/L in hypovolemic hypotonic hyponatremia it can be caused by:
Definition
Diuretics
Adrenal Insufficiency
Term
What is the most common type of hyponatremia?
Definition
Euvolemic hyponatremia (60%)
Term
What is the presentation of euvolemic hyponatremia?
Definition
No clinical signs of fluid overload/hypovolemia
Term
Causes of euvolemic hyponatremia
Definition
SIADH (can be caused by tumors, CNS disorders, trauma, Drug induced, pulmonary disease, mechanical ventilation, idiopathic)

Drugs that cause SIADH: nicotine, antipsychotics, TCAs, DDAVP, oxytocin, 'ecstasy'

Hyperthyroidism, Adrenal insufficiency

Exercise associated hyponatremia
Term
Treatment of euvolemic hyponatremia
Definition
1. If possible, correct underlying cause
2. treatment will vary depending on acute/chronic onset and if patient is symptomatic
3. IF SIADH:
a. Acute: Hypertonic Saline
b. Chronic: Fluid restriction (alternatives-demeclocycline, urea, lithium)
Term
Causes of hypervolemic hyponatremia
Definition
**Increased ECF volume (+ edema) but decreased effective circulating volume

heart failure

cirrhosis

renal failure

nephrotic syndrome
Term
With hypervolemic hypotonic hyponatremia urine Na is (< or >) 20 mEq/L
Definition
Less than 20 (AVP release causes renal sodium and water retention but water>Na)
Term
When would you use a vasopressin antagonist in hyponatremia?
Definition
HYPERvolemic hyponatremia
Term
Vasopressin Antagonist Examples
Definition
"vaptan" class

1. Tolvaptan
2. Conivaptan

$$$$$$
Term
Vasopressin Antagonist MOA
Definition
Inhibit aquaporin formation in kidneys

More free water is excreted
No hypotension
Term
In acute onset hyponatremia correction should be _______ while with chronic onset correction should be ______
Definition
Acute = rapid correction

Chronic = slow correction
Term
What should be monitored in hyponatremia treatment
Definition
urine osmolarity and sodium
Term
How quickly can hyponatremia be corrected?
Definition
<10-12 mmol/L over 24 hours
**Aim for 8 mmol/L per day

<18 mmol/L over 48 hours

**IF acute or symptomatic chronic hyponatremia: 1-2 mmol/L/hr (once symptoms resolve, reduce rate)

DO NOT exceed because brain cells will swell-->exception to these rates is ONLY if head injury within the last 2 hours--then can correct at a faster rate
Term
1 mL/kg of 3% saline increases Na by _____ mEq/L
Definition
~1 mEq/L increase

***20-30 mL/hr will raise [Na] by 8 mEq/L/day
Term
for every 1 mL of 3% saline how much ICF water gets puled into the ECF?
Definition
~7 ml from ICF (therefore, if infuse 50 mL 3% NaCl-->400 mL water added to ECF [50mL + 7(50mL)])
Term
does hypertonic saline cause rapid or slow redistribution?
Definition
Rapid
Term
Uses of hypertonic saline:
Definition
1. Rapid onset hyponatremia (because quick redistribution) with symptoms of urine concentrations over 200 mOsm/kg water and clinical euvolemia or hypervolemia
2. Head injury
Term
ADRs of hypertonic saline
Definition
1. electrolyte disturbances
2. pulmonary edema
3. coagulopathies
Term
T or F: hypernatremia is always hypertonic
Definition
True (But can be hypertonic and not hypernatremic)
Term
Signs and Symtoms of Hypernatremia
Definition
Thirst
Tachycardia
Low CVP or PCWP
Decreased urine output (unless DI)
CNS (seizures)

The onset of hypernatremia will affect severity
Term
Causes of and treatments for hypovolemic hypernatremia
Definition
Water loss > Na loss

Insensible Losses, vomiting, diarrhea

Tx:
1. Calculate free water deficit
2. Administer D5W, 1/4NS, 1/2NS, NS (may still be hypotonic in comparison to blood)
Term
causes of and treatments for Hypervolemic hypernatremia
Definition
Sodium overload
Mineralocorticoid excess

Gain of Na greater than the gain of water

**Bodies ability to work is problematic

Tx:
1. Restrict Na
2. Give Diuretic
Term
Causes of and treatments for Euvolemic hypernatremia
Definition
CHRONIC ONLY

DI
Osmotic diuresis

Tx:
1. D5W (will disperse evenly)
2. Treat DI if required
Term
How to calculate water deficit
Definition
Water deficit = TBW x [(SNa/140)-1]

**If hyperglycemic, correct serum Na by adding 1.7 mEq/L for every 100 mg/dL increase in serum glucose
Term
Desmopressin
Definition
Treatment for Central DI

DDAVP

intranasal, PO, IV, SC, IM

Synthetic vasopressin analog: antidiuretic (V2):vasopressor (V1) ratio (2000-4000:1) vs. vasopressin ratio (1:1)

Other uses: nocturnal enuresis, acute uremic bleeding (increases plasma Factor VIII activity)

Dosing: 2-4 mcg IV or SQ BID or 0.1-0.8 mcg PO BID-TID
Duration of action: 8-12 hours
Term
Two types of diabetes insipidus
Definition
1. central

2. nephrogenic
Term
Treatment for nephrogenic DI
Definition
1. sodium restriction and a thiazide-->promotes proximal water reabsorption
2. NSAIDs may potentiate the activity of ADH (ex: indomethacin)
3. lithium-amiloride: inhibits lithium uptake into collecting duct
Term
How to treat sodium overload
Definition
loop diuretics to facilitate sodium overload

D5W to replace water
Term
Loop Diuretics MOA and examples
Definition
Furosemide
Bumetanide
Torsemide
Ethancrine Acid

MOA: inhibits Na-K-Cl carrier on Loop of Henle

20% of Na fraction gets excreted (most)
Term
Thiazide MOA
Definition
Inhibits Na-Cl carrier in DISTAL Tubule

3-5% of Na fraction gets excreted
Term
Potassium Sparing Examples and MOA
Definition
MOA: inhibits Na channel in cortical either directly or by decreasing aldosterone activity

Direct: Amiloride, Triamterene

Indirect: Spirnolactone, Eplerenone

Only 1-2% of Na gets excreted
Term
Distal sodium reabsorption can occur with chronic loop diuretic use. What should you do if/when this occurs?
Definition
Add thiazide
Term
What occurs with renal insufficiency with diuretics?
Definition
Filtered Na load decreases with GFR

-larger and more frequent dosing may be required
-with continuous infusion-load first
Term
ADRs of Thiazides
Definition
**Only use if CrCl>50mL/min

Hypercalcemia
Hypokalemia
Term
ADRs of Loop Diuretics
Definition
Hypokalemia
hypomagnesemia
metabolic aklalosis
highly protein bound
Term
ADRs of K+ sparing diuretics
Definition
Hyperkalemia
Gynecomastia (esp. with spirnolactone)
Term
T or F: serum sodium concentrations typically have little variation.
Definition
T: normally vary by less than 2-3% in healthy individuals
Term
T or F: Potassium in almost completely reabsorbed by the kidney.
Definition
T: 80-90% of filtered K is reabsorbed
Term
Which endogenous protein most affects Ca levels?
Definition
Albumin
Term
Where is the majority of Mg stored in the body?
Definition
1. bone
2. muscle
Term
T or F: there is hormonal control of Mg.
Definition
F-no hormonal control
Term
T or F: serum sodium concentrations typically have little variation.
Definition
T: normally vary by less than 2-3% in healthy individuals
Term
T or F: if there is a low measured Ca level, it always means you need to give more Ca.
Definition
F: must check albumin, if albumin is also low, then ionized Ca may be normal
Term
Regulation mechanisms of Ca
Definition
1. PTH: stimulates release of Ca from bone, decreases Ca excretion, increases vitamin D (from kidney) to increase Ca absorption in GI
2. Calcitonin: inhibits Ca bone resorption (bone breakdown)
Term
Causes of hypercalcemia
Definition
1. increased abosorption
2. decreased elimination
3. increased bone resorption (bone breakdown)

Neoplasms: MOST COMMON-esp carcinomas of lung, breast, multiple myeloma-->PTH-related protein released

Medications: increased renal reabsorption: [1] thiazides and [2] lithium

Endocrine diseases

Immobilization (osteoclasts work alot)

Paget's disease

rhabdomylolysis (breakdown of muscle cells)
Term
Signs of hypercalcemia
Definition
RENAL: kidney stones, renal tubular dysfunction, polyuria, polydipsia

GI: anorexia, N/V, constipation

CV: QT shortening, ventricular arrhythmias

Musculoskeletal problems
Term
Clinical Presentation of hypercalcemia (levels)
Definition
mild-moderate: 10.5-13 mg/dl

severe>13 mg/dl

crisis>15 mg/dl (Medical emergency)
Term
What is ALWAYS the first step in treating hypercalcemia?
Definition
Hydration
Term
What should you avoid in the treatment of hypercalcemia?
Definition
IV phosphate (because will precipitate)

However, bisphosphonates are ok to use (use IV not PO because need quick onset)
Term
What is the general treatment plan for hypercalcemia
Definition
1. Expand Intravascular volume
then...
2. Promote Ca excretion
Term
Treatment options (drugs) for hypercalcemia
Definition
1. Loop diuretics (block Ca reabsorption)-avoid in fluid restricted patients (CKD stages 4/5, heart failure)

2. Calcitonin (Miacalcin)

3. Bisphosphonates (IV b/c PO is slow)-first line for CA associated hypercalcemia/long-term control; caution in renal osteodystrophy secondary to chronic kidney disease

4. Gallium nitrate and mithramycin (no longer used b/c poorly tolerated)

5. Corticosteroids if caused by malignancy (not usually used)
Term
Calcitonin (Miacalcin)
Definition
Fast onset (1-2 hr)
For Tx of hypercalcemia
derived from salmon
SC or IM
Tachyphylaxis with chronic therapy (due to antibody formation)
Term
What is first line for cancer associated hypercalcemia?
Definition
IV bisphosphonates (etidronate, pamidronate, zoledronate, ibandronate)
Term
Hypocalcemia causes
Definition
1. hypoparathyroidism (post-op)
2. vitamin D deficiency (uncommmon)
3. hypomagnesemia-->impaires PTH secretion
4. Oral phosphorous therapy, sodium phosphate bowel preparations
5. Drugs (loops, phenytoin, calcitonin, barbiturates)
Term
Clinical presentation of hypocalcemia
Definition
hallmark-tetany (facial, extremity muscle spasms, cramps)

Neuro: weakness, fatigue, seizures, confusion, depression, memory loss (chronic)

CV: hypotension, bradycardia, QT prolongation, unresponsive to vasopressors (b/c not enough calcium in smooth muscle to contract?)
Term
Which loop diuretic should you give if you have a sulfa allergy
Definition
Ethacrynic acid
Term
Treatment of hypocalcemia
Definition
1. Correct the underlying cause
2. Check albumin-if Alb low then ionized Ca may be normal

If chronic: check vit D and PTH
If acute: give 100-300 mg elemental IV Ca (pref. gluconate salt-can do peripheral line)
Term
Which can be given IV peripherally: calcium chloride or calcium gluconate?
Definition
Gluconate (9% elemental Ca= less chance of precipitating)

CaCl is only reserved for life threatening emergencies because 27% elemental Ca
Term
What is Calcium acetate most used for?
Definition
To decrease phosphorus (sequesterant)
Term
The lab values for which nutrients are not very indicative of their levels in the body?
Definition
Mg, Phos, K
Term
where is most of the body's phosphorus found?
Definition
Skeleton 85%
ICF 14%
ECF 1%
Term
In what form is phosphate usually found?
Definition
1. ATP,2,3-diphosglycerate (DGP), fructose 1,6-diphosphate

2. Inorganic phosphate (PO4) mostly in ECF and some in ICF
Term
T or F: phosphate is mostly renally eliminated by filtration.
Definition
T: ~80-90% reabsorbed in proximal tubule
Term
Causes of hyperphosphatemia
Definition
1. endogenous release or renal failure (causes decreased vit D concentrations, decreased Ca concentrations, increased PTH) 2. Tumor lysis and rhabdomylosis (acute lymphatic leukemia, Burkitt's lymphoma-chemo->kills all cells which expel their PO4) 3. DKA 4. Increased intake (Acute phosphate nephropathy)
Term
Clinical presentation of hyperphosphatemia
Definition
precipitation (of Ca and PO4) can cause obstructive nephropathy

likely when Ca x PO4 = 50-60 (about double the normal product)
(Goal is <55 in CKD)
Term
Treatment for hyperphosphatemia
Definition
Phosphate binders to decrease GI absorption
**Ca is preferred (Ca acetate) except with elevated Ca x PO4 product then try non-calcium binders (lanthanum carbonate, sevelamer, carbonate, aluminum salt-->may be toxic so dont give with CKD)

**The only way to decrease PO4 is to not absorb it in the first place
Term
Who has a higher incidence of hypophosphatemia
Definition
Critically Ill patients
Term
Causes of hypophosphatemia
Definition
1. decreased absorption
2. enhanced excretion
3. acute volume expansion-->shifts PO4 out of serum
4. Extracellular to intracellular redistribution-->RAPID REFEEDING (if too quick then the body's phosphate will rush into cells to help breakdown glucose for energy (ATP))
Term
Presentation of hypophatemia
Definition
1. depleted intracellular ATP
-impaired respiratory function
-myalgias
-muscle weakness
-bone pain
-impaired cardiac muscle function
2. Decreased oxygen delivery (decreased 2,3-DPG concentrations in RBCs)
-Rigid RBCs become trapped in spleen-hemolysis
-impaired WBC functions-increase risk for infections
Term
Treatment for hypophosphatemia
Definition
Severe:
IV, sodium or potassium phosphate (15 mmol will correct by 0.5 to 0.8 mg/dl)
Suggested max infusion rate = 9 mmol phos/hr (risk of symptomatic hypocalcemia, soft tissue calcification, rapid K+ could stop heart)

Mild to Moderate:
PO
50-60 mmol/d in divided doses
neutra-phos (8 mmol/packet)
*Dose limited by osmotic diarrhea

**Caution in CKD because could cause hypoerphosphatemia if correct too quick
Term
where is potassium found?
Definition
75% skeletal muscle
25% in liver and RBCs
Term
potassium disturbances mainly affect ________.
Definition
neuromuscular activity (especially cardiac function
Term
T or F: Most people get the required amount of K+ daily.
Definition
T
Term
T or F: Potassium is mainly filtered and reabsorbed in the proximal tubule and loop of Henle.
Definition
T
Term
What 4 things regulate potassium?
Definition
1. Insulin
2. Catecholaimes
3. Aldosterone-->promotes K excretion
4. Acid-base balance (hydrogen gets exchanged for K)
Term
Is hyperkalemia associated with acidosis or alkalosis?
Definition
acidosis (body is trying to compensate for the acidosis, so is exchanging H for K)
Term
Causes of hypokalemia
Definition
1. diuretics-loops and thiazides (inhibit reabsorption of Na and excretion of K and decreased volume stimulates aldosterone)
2. Diarrhea
3. Vomiting/NG suctioning-loss of HCl=alkalosis
4. Hypomagnesemia
Term
Drugs that cause hypokalemia
Definition
diuretics, high-dose penicillins, sorbitol, laxatives, beta-2-receptor agonists, tocolytics, theophylline, insulin
Term
Clinical presentation of hypokalemia
Definition
Mild: asymptomatic usually; N/V,constipation, weakness

Moderate: cramping, weakness, myalgias, malaise

Severe: paralysis, rhabdomyolysis, respiratory distress, ECG chages (ST depression, T-wave inversion, U-wave elevation), arrhythmias, death
Term
What must you correct first before fixing hypokalemia?
Definition
magnesium
Term
To fix hypokalemia would you prefer NS or dextrose containing solutions?
Definition
NS because dextrose can cause insulin release and worsen hypokalemia
Term
Potassium burns in peripheral veins. In order to help with that people often give ___________. What is the problem with that.
Definition
Lidocaine can be infused to, but if do this then it cant be felt if it slipped out of the vein

alternative--slow the rate! no more than 10 mEq/100 mL
Term
10 mEq of K will correct about _______ in serum
Definition
0.1 mEq/L

**in sereve hypokalemia it only changes it by 0.05 mEq/L
Term
Treatment of hypokalemia
Definition
1. Replace Mg first
2. IV or PO K replacement
3. for every 1 mEq/L decrease below 3.5 mEq/L there is a total body deficit of 100-400 mEq
4. K-sparing diuretics may be considered instead of chronic oral replacements
Term
T or F: Most potassium salts are control release.
Definition
T--so dont crush
Term
Is hyper or hypo kalemia more common?
Definition
Hypo-because of K-depleting diuretics
Term
Most common cause of hyperkalemia
Definition
Over replacement with IV potassium

Other causes: overuse of K supp, dietary intake, decreased excretion esp with AKI (ACE-Is, ARBs), redistribution into ECF (acidosis, DM)
Term
Presentation of hyperkalemia
Definition
Cardiac (heart palpitations), neuromuscular, smooth muscle cell function

usually asymptomatic

Severe: sine wave, ventricular fibrillation, lose p wave--melds with QRS complex
Term
Treatment of hyperkalemia
Definition
Severe:
1. Ca for EKG abnormalities
2. Dextrose/insulin (IV)
3. Albuterol good short term with kids
4. Bicarb is acidemic
5. Hemodialysis PRN (if severe)

Mild/Moderate
1. Loop diuretics (K wasting)
2. Sodium polystyrene sulfonate (SPS, Kayexalate)-exchange resin (Na for K)-induces diarrhea
-oral preferred (over enema-must always use premade product if use enema)
-caution in patients with ileus (causes intestinal necrosis)
Term
primary intercellular cation
Definition
K
Term
What tightly regulates K?
Definition
Na/K/ATPase pump (insulin, catecholamines, acid/base balance)
Term
Magnesium distribution
Definition
Primarily ICF (67% bone and 20% muscle)
Term
What is the second most abundant ICF cation
Definition
Mg
Term
Where is Mg reabsorbed?
Definition
loop of Henle
Term
What factors affect Mg reabsorption in the loop of Henle?
Definition
1. Serum Mg levels: b/c no hormonal control movement is concentration dependent
2. Intraluminal Na and ECF volume status: decreased ECF volume causes increased Mg reabsorption (b/c decreased luminal flow and increased Na reabsorption) AND low Na diet causes increased Mg reabsorption
3. PTH increases Mg reabsorption
Term
What are the central roles of Mg
Definition
cellular function and cofactor in numerous biological reactions (especially systems depending on ATP) and enzymes

Also:
1. mitochondrial and cell membrane function
2. protein synthesis
3. PTH secretion
4. nerve conduction, membrane stabilization
5. INHIBITS CALCIUM CHANNELS
Term
Hypomagnesemia is most common is what kind of patients?
Definition
ICU patients
Term
Causes of hypomagnesemia
Definition
1. GI losses: decreased absorption/intake (ex: alcoholism), increased loss
2. Renal losses: most common with loops and thiazides (also with foscarnet, aminoglycosides, amphotericin)
3. Commonly associated with hypocalcemia
Term
T or F: Serum Mg = total body Mg
Definition
False-most in cells so poor reflection
Term
Clinical Presentation of hypomagnesemia
Definition
Mild to moderate: 1-1.5 mEq/L
Severe: <1 mEq/L

typically asymptomatic BUT other electrolyte abnormalities (low K, Ca) can be present and difficult to assess Mg deficit alone

MOST prominent symptom: HYPOCALCEMIA (possibly due to PTH secretion, decreased vit D, skeletal resistance to PTH)
Term
Signs and Symptoms of hypomagnesemia
Definition
Neuromuscular: tetany, twitching, weakness, seizures, coma, ataxia, tremor

GI: N/V

CV: HEART PALPITATIONS and ARRHTYMIAS-torsades de pointes (digoxin induced, ventricular fibrillation)

Moderate to severe: prolonged PR interval, progressive widening of QRS complex, flattened T waves
Term
Treatment of hypomagnesemia
Definition
Mild-moderate: Magnesium oxide 400-800 mg TID-QID (60% elemental)--Diarrhea is dose-limiting

Severe: IV MgSO4 (1 gram = 8.12 mEq)
may require 8-12 g in the first day then 4-6 g/day for 3-5 days

Decrease dose by 50% in kidney disease

*Must correct hypoMg before other electrolyte disturbances
Term
Hypermagnesemia occurs when _______.
Definition
when intake exceeds kidneys' ability to excrete (stage 4-5 CKD, elderly)
Term
T or F: hyperMg is very uncommon
Definition
T and symptoms are rare when Mg<3mg/dl
Term
Symptoms of hyperMg
Definition
Rare unless Mg>3 mg/dl

Listed by increasing severity:
sedation
Hypotonia
Hporeflexia
Somnolence
Coma
Muscle paralysis
Respiratory depression
Complete heart block
Asystole
Term
Treatment of HyperMg
Definition
Decrease Mg intake
Loop diuretics to promote excretion
Antagonize Mg physiologic effects with Ca (use IV calcium chloride 10%--avoid PO Ca)
Term
What is first line therapy for hyperkalemia with ECG changes?
Definition
Calcium gluconate
Term
You shouldnt exceed ____ mEq with potassium tablets
Definition
60 mEq--better tolerated with food
Term
Sign of chromium deficiency
Definition
hyperglycemia
Term
sign of selenium deficiency
Definition
cardiac myopathy
Term
sign of copper deficiency
Definition
anemia, hematological changes
Term
signs of zinc deficiency
Definition
alopecia

decreased wound healing

diarrhea
Term
half life pre-albumin
Definition
~2 days (short)
Term
what binds to prealbumin
Definition
thyroxine

retinol
Term
how often should you check pre-albumin in high risk patients?
Definition
twice weekly
Term
what is the normal levels of prealbumin?
Definition
18-38 in women
20-40 in men
Term
T or F: prealbumin is a precursour for albumin
Definition
F
Term
Half-life of albumin
Definition
18-20 days
Term
Normal serum level of albumin
Definition
3.5-5.4 g/dL
Term
PEM
Definition
protein energy malnutrition (aka Marasmus)
Term
What type of malnutrition in protein deficient but not calorie deficient?
Definition
kwashiorkor
Term
Stressed starvation
Definition
Quicker decline

hypermetabolic
hyperglycemic: increased insulin-->ressistance; high glucose prevents fat metabolism
Protein sparing effect (of burning fat) is minimal b/c of decreased fat metabolism

So patient who hasnt eaten in 4-5 days, is hyperglycemic (control with insulin drip), very protein deficient (give proteins), not burning fat but protein instead

Seen to result in death sooner than non-stressed starvation
Term
Nitrogen Balance
Definition
Nitrogen(IN)-[Nitrogen(OUT) + 4g]
Term
Who soon after hospitalization should nutritional screening take place (according to JACHO)
Definition
within 24 hours
Term
Nutritional Screening vs Nutritional Assessment
Definition
Screening: by a nurse within first 24 hours to determine risk of malnourishment

Assessment: done by a dietician for patients who are "at risk" + monitored throughout stay
Term
Low albumin can result in what?
Definition
edema
Term
healthy BMI
Definition
20-24.9 kg/m2
Term
KY ranks _____ in overweight people
Definition
7th (69.1%)
Term
Modest weight loss SIGNIFICANTLY reduces mortality due to what?
Definition
diabetes related conditions
Term
two low fat diet
what was the reason for such a high failure rate?
Definition
1. Pritikan diet
2. Ornish Diet Plan

Severe fat restriction was too stringent
Term
What is the ideal ratio for omega-6:3
Definition
4:1 or 6:1
(currently 20:1 up to 50:1)
Term
Omega-6 can be bad why?
Definition
goes to arachadonic acid-->inflammatory prostaglandins + TXA=vasoconstriction
Term
Omega-6 are ______ series and omega-3 are ______ series
Definition
Omega-6 are even series-->TXA2, PGE2

Omega-3 are odd series-->TXA3 (much less clotting and inflammation)
Term
What are the two metabolites of omega-3 FA
Definition
EPA and DHA
Term
What is the key concept of the omega-3 FA diet?
Definition
Minimize omega-6, not just add fat sources

(ex: eat fatty fish at least 2 times per week)

good for CV patients
Term
Linoleic acid is omega-___
Linolenic acid is omega-___
Definition
Linoleic= omega-6
Linolenic= omega-3
Term
Which type of fat is most dominant in the Mediterranean diet?
Definition
monounsaturated FA
Term
what is the American equivalent to the Mediterranean diet
Definition
Sonoma Diet-low cal low sugar
Term
what diet is the same as the low GI index + high fiber
Definition
south beach
Term
What is a big problem with using meridia for weight loss?
Definition
people with CAD, CHF, arrhythmias, or stroke history should NOT take it...mainly seen in overweight people who are most interested in taking this drug
Term
T or F: dietary supplement labels can NOT claim that the product can diagnose, prevent, mitigate, treat, or cure a specific disease
Definition
T: that would be a drug if they could
Term
Absolute TPN indications
Definition
1. inability to absorb adequate nutrients (massive small bowel resection, short gut syndrome)
2. Bone marrow transplant with GVHD (graft vs. host disease) of the gut or chronic malabsorption from RADIATION
3. Severe ACUTE pancreatitis requiring bowel rest for 7-10 days
4. Enterocutaneous fistulas
5. Enteral feeding access not possible due to upper GI obstruction
6. Low birth weight infants
Term
Relative TPN indications
Definition
1. NPO over 7-10 days
2. Malabsorption from radiation/chemo
3. major GI surgery with suspected bowel ischemia
4. post-op small bowel obstruction
5. severe brain injury with enteral access not acheived within 72 hr
6. ongoing GI hemorrhage
7. prolong use of vasopressors, unable to advance enteral nutrition toward goal (decreased blood supply to GI-ischemia)
Term
why dont we give TPN in the terminally ill?
Definition
TPN is a medical treatment (so not with Hospice patients)
Term
optimal nitrogen balance
Definition
+1 - +4
Term
IV Fat emulsions are what type of fat?
Definition
omega-6
Term
what type of fat is only given PO?
Definition
MCT (not for TPN)
Term
what vitamin must be added to TPN separately?
Definition
Vitamin K
Term
what trace element should you not give to people in renal failure without dialysis
Definition
selenium
Term
what trace elements should you not give in cholestatic liver disease?
Definition
Mn and Cu
Term
what electrolyte should be added last to TPN?
Definition
Phos (add Ca first to interact with AA-becomes monobasic, less likely to react with Phos)--main thing is to make sure they are separated
Term
Things that help decrease the risk of Calcium-phos precipitation
Definition
1. lower concentrations
2. acidic pH
3. higher AA concentrations
4. lower temps
5. separate when mixing
6. faster infusion rate

**use CaCl2 salt (not carbonate)
Term
Things to do to decrease chance of bacterial growth in TPN
Definition
1. acetate (CAA) > 35 mEq/L-prevents bacterial growth (EXCEPT candida)

2. acidic and hypertonic not ideal for bacterial growth

3. Decrease Candida growth by cooling to 4 degrees C

4. Infuse within 36 hr of making***MVI have 36 hr BUD once added

5. Alb increases growth so try not to include in TPN
Term
Medications often added to TPN
Definition
Insulin-can stick to bag (variable infusion levels)

H2RA-famotidine

Heparin

Do NOT ADD: Alb or Iron Dextran (would be ok, but nothing else in compatible to it)
Term
Even though peripheral TPN decreases infection rate what are 2 issues?
Definition
1. large volume
2. phlebitis (>600 mOsm)
Term
PICC
Definition
peripherally inserted central catheter
Term
big issues with TNA vs. TPN
Definition
TNA:
cant filter with 0.22 micron filter (standard with TPN)
cant visually detect particulate matter (ex: Ca-PO4 PPT)
Enhanced microbial growth potential-extended fat hang time
Term
How to begin TPN administration
Definition
start at 25 mL/hr x 8 hr
increase by 25 ml/hr Q8H until goal

if blood sugar >250 do not increase rate

TO D/C TPN:
taper by 25 mL/hr Q6-8H OR
decrease by 1/2 rate for 3-6 hr

**Concern of hypoglycemia if stop too fast (b/c insulin has longer 1/2life than glucose)

NOTE: no need to taper if other food source (Ex: started PO or enteral)
Term
PEG
Definition
percutaneous endoscopic gastrostomy (sam as G-tube)
Term
What is the smallest enteral feeding tube?
Definition
J-tube (4-10 French)
*easily clogged
Term
which enteral tube do you not usually put food down?
Definition
NG-tube, usually just meds
Term
How to begin Enteral Feeding:
Definition
1. slow at first to determine tolerance (at 10 mL/hr)

2. increase by 10-25 mL/hr Q6-8H if feeding continuously

3. DO NOT dilute isotonic formulas--no benefit
Term
Which type of protein is easiest to absorb? Intact proteins, small peptides, or free amino acids?
Definition
Small peptides (usually absorbed as tri- and dipeptides)
Term
T or F: all enteral formulas contain fiber.
Definition
F
Term
T or F: all enteral formulas contain linoleic and linolenic acid fats.
Definition
T
Term
When is it good to give someone MCT?
Definition
Enteral-when patient cant produce lipase (ex: CF kids, pancreatic CA, some diabetics)
Term
When are hypertonic enteral formulas a concern and why?
Definition
when they are given into the lower GI tract because they can cause diarrhea (if given at top, can decrease tonicity by end)
Term
T or F: Metamucil can go down a tube feed?
Definition
F-will 'concrete it'

soluble fiber is ok down tube
Term
if enteral tube gets clogged what should you do?
Definition
put hot water down it
Term
What can cause diarrhea in enteric feeding?
Definition
drugs! (ex: KCl if not enough water)
sorbitol
prolonged antibiotics
hyperosmotic feeding
laxatives
hypoalbuminemia-bowel edema
lactose intolerance/fat malabsorption
rapid GI transit
low-residue intolerance (lack of bulk)
bacterial contamination (change bag Q24H)
Term
issue with digoxin and enteral nutrition
Definition
Digoxin undergoes acid hydrolysis normally in stomach--if bypass stomach can get higher levels
Term
Cipro + other fluoroquinolones and EN
Definition
with J-tube: decreased absorption of drug

binds to EN protein, chelation with cations (?)

hold tube feed (cipro), adjust dose, or give in duodenum

Moxi:best F with EN
Term
Sevelamer issues with tube feeding
Definition
Clogs tube feed (same with other viscous/thick meds)
Term
What is the issue with acidic medications and enteral nutrition? (examples)
Definition
Curdles intact protein (dont mix with enteral nutrition products)

Ex: KCl, guafenesin, in flavorings
Term
What is the issue with giving elixirs with enteral nutrition?
Definition
precipitates inorganic salts in enteral formula
Term
Can you give microencapsulated drugs via feeding tube?
Definition
Sometimes-if the tube is large enough

Do NOT crush the microcapsules

How:
Mix pellets with water or acid and flush down feeding tub
Careful about potentially clogging tubes

Ex: Diltiazem, ferrous gluconate, nizatidine, pancreatic enzymes, verapamil
Term
Issues with phenytoin and EN
Definition
phenytoin has decreased absorption with EN

hold tube feed for 1 hour before and after
Term
Issues with itraconazole and EN
Definition
decreased absorption (improved in fasted state)

hold tube feed 1 hr before and after (or double dose)
Term
Issues with levothyroxine and EN
Definition
decreased absorption, but better when fasted

hold tube feed before and after for 1 hr (or adjust dose)
Term
Issues with warfarin and EN
Definition
with VITAMIN K Enteral formulas
+Warfarin can bind to proteins in EN formula

transitioning to PO may reduce dose (if increased it to compensate for vit K)

HOLD tube feed 1 hr before and after (or adjust dose based on INR if continuous EN)
Term
Issues with carbamazepine and EN
Definition
decreased absorption because sticks to tubing

Dilute suspension and monitor efficacy

hold tube feeding if not Gastric (dont hold if in stomach)
Term
Issues with PPIs and EN
Definition
Enteric coated

Cant crush and mix with water because will be less effective

For liquid preparation-need to dissolve in bicarb

Zegerid omeprazole and bicarb powder

Lansoprazole granule packets have xanthan gum--clogging
Term
How much water should be used to flush EN tube before and after each medication?
Definition
15-30 mL water
Term
Which tube is preferred for medications placement in EN?
Definition
G-tube

1. larger tube
2. less irritation by meds

If cant give med via G-tube, must finely crush and mix with ~60 mL water for J-tube
Term
Maillard reaction
Definition
AA + Dextrose -->browning

instability issue (seen with PN)
Term
H2RA stability in PN
Definition
cimetidine and famotidine greater stabilty than ranitidine
Term
what vitamin is added in greater amounts when at risk for refeeding syndrome?
Definition
thaimine
Term
Ca/PO4 PPT safety factors
Definition
(mEq of Ca + mM of Phos) x 100/ PN Volume

for AA concen over 2.5% factor should be less than 4


Easier Way: (if AA concen >4%)
for 2:1: Ca x P less than 300
for 3:1: Ca x P less than 150
Term
T or F: positive charges can be disruptive to PN?
Definition
T, can be disruptive to emulsifier (fats) in TNA
Term
For extended dating on TNA bags--homecare stabilty guidelines
Definition
AA concen at least 4% Dextrose at least 10% Fats at least 2% sum of divalent cations less than 20-25 mEq/L sume of monovalent cations less than 150-200 mEq/L
Term
who should NOT get 3:1 PN?
Definition
pediatrics--they require high Ca/Phos concentrations--too risky

L-cysteine is added which is good for Ca/Phos but disrupts fat emulsion
Term
Aluminum concentration is limited in PN
Definition
limited to 25 mcg/L

renal function and CNS toxicity
Term
What is the filter size for a 2:1? 3:1?
Definition
2:1: 0.22 micron

3:1: 1.2 micron

dont remove filters
Term
what is given to decrese catheter related occlusions?
Definition
low dose warfarin

give alteplase for suspected thrombus
Term
PN and Ceftriaxone issues
Definition
Ceftriaxone warning with IV Ca--precipitate

contraindicated in neonates

Flush line thoroughly in other patients
Can also try to hold Ca from PN for ~48 hrs after last rocephin dose

Consider ceftriaxone alternatives
Term
Foods affect on Theo-24
Definition
can cause dose dumping-dont take with food
Term
What is the hallmark sign of refeeding syndrome?
Definition
hypophosphatemia (hypoMg and hypoK)

(edema, thiamine and folate deficiencies)
Term
T or F: for EN elixirs and susp are favored over syrups
Definition
T
Term
T or F: you can dilute hypertonic meds for EN
Definition
T
Term
What are some drugs that have acid-dependent absorptions?
Definition
Fe
carbamazepine
ketoconazole
itraconazole
tetracyclines
Term
during stress your body runs out of which AA?
Definition
arginine (conditionally essential)
Term
what electrolyte is of great concern in kidney disease?
Definition
Phosphorus (even on dialysis have trouble eliminating)
Term
T or F: restricting Na in the diet is critical in liver disease
Definition
T
Term
Severe chronic protein restriction in liver disease will result in ________.
Definition
Protein Calorie Malnutrition
Term
patients with short bowel will most benefit from what type of enteral formula?
Definition
semi-elemental (small di and tri peptides)

have MCT oil for easiest abosprtion

also used when transitioning from TPN to EN
Term
What are specific needs in surgery, trauma, and burn patients?
Definition
HIGH:
Calories
Protein
K
Phos

Supp:
vit C
glutamine, arginine, omega-3->immune function
selenium
BCAA

Increased zinc for wound healing
Term
What is the greatest concern when feeding COPD patients
Definition

Dont overfeed them

 

Increased CHO-->CO2 which they are already retaining

 

can give fats (least amount of CO2)--BIG DIARRHEA

still maintain high protein diet

Term
Issues with feeding ARDS patients
Definition

Supplement omega 3 FA and decrease/eliminate omega 6

 

omega 6= inflammation

 

ARDS (Acute Respiratory Distress syndrome) associated with severe inflammation

Term
What drug stimulates lipoprotein lipase activity and possibly improves IVFE associated hyper-triglyceridemia?
Definition
Low dose heparin
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