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aminophylline to theophylline

1 aminophylline / 0.8 theophylline
measurements
- 1 grain / 65 milligrams
- 1 cup / 8 oz
- 1 pint / 473 ml
- 1 quart / 2 pints (946 ml)
- 1 gallon / 4 quarts (3785 ml)
BMI

weight (lbs) / height (cm)²X 704.5
BMI classifications
- < 18.5: under weight
- 18.5 - 24.9: normal
- 25 - 29.9: over weight
- > 30: obese
Ideal Body Weight (IBW)
- men: 50 + 2.3(ht (in inches) - 60)
- female: 45.5 + 2.3(ht (in inches) - 60)
BUN:Scr ratio

ratio > 20 indicates dehydration
CrCl
- (140 - age) x (wt in kg) / 72 x Scr
- underweight: (<18.5) use actual weight
- normal: (18.5 - 24.9) use IBW
- overweight: (>25) use adjusted body weight
- adj body weight: IBW + 0.4 (TBW - IBW)
- *TBW - actual weight
GFR levels
- >90: stage 1
- 60 - 89: stage 2
- 30 - 59: stage 3
- 15 - 29: stage 4
- <15 : stage 5
Specific Gravity
- SG = weight (g) / volume (ml)
- water: specific gravity of 1
TPNs
- Carbs: 4 kcal / g
- Fat: 9 kcal / g
- protein: 4 kcal / g
- dextrose: 3.4 kcal / g
- amino acids: 4 kcal / g
- glycerin: 4.3 kcal / g
- IVFE 10%: 1.1 kcal / ml
- IVFE 20%: 2 kcal / ml
- IVFE 30%: 3 kcal / ml
Determining Fluid Needs

When weight over 20 kg: 1500 ml + (20 ml)(wt in kg - 20)
Protein requirements
- non-hospitalized: 0.8 - 1 g/kg/day
- hospitalized: 1.2 - 2 g/kg/day
Activity factor
- Confined to bed: 1.2
- Out of bed: 1.3
BEE (Basal Energy Expenditure)

BEE = non-proteins or lipids and dextrose
Determining grams of nitrogen from protein
- Nitrogen intake = grams of protein intake / 6.25
- NPC:N ratio - first calculate nitrogen intake
- - then divide non-protein (lipids and dextrose) by grams of nitrogen
Corrected Calcium
- Ca_corrected= calcium_serum + (4.0 - albumin)(0.8)
- calcium + phosphate: should not exceed 45mEq/L
mOsml/L

mOsml/L = wt of substance (g/L) / MW (g/mole) X (# of particles) X 1,000
Dissociation of particles for mOsml/L
- dextrose: 1
- mannitol: 1
- potassium chloride: 2
- sodium choloride: 2
- sodium acetate: 2
- calcium chloride:3
- sodium citrate: 4
Isotonicity: E-value
- E = (58.5)(i) / (MW of drug)(1.8)
- i = dissociation of ions
- 1 ion: 1
- 2 ions: 1.8
- 3 ions: 2.6
- 4 ions: 3.4
- 5 ions: 4.2
- *add 0.8 when adding an ion
moles and millimoles
- moles = g / MW
- mmols = mg / MW
mEq formula
- (mg x valence) / MW
- OR
- mEq = mmlols X valence
compound and its valence electron for mEq formula
- ammonium chloride (NH4Cl): 1
- potassium chloride (KCl): 1
- potassium gluconate: 1
- sodium acetate: 1
- sodium bicarbonate: 1
- calcium carbonate: 2
- calcium chloride: 2
- disodium phosphate: 2
- ferrous sulfate: 2
- magnesium sulfate: 2
Temperature Conversions
- Celius = (F - 32) / 1.8
- Farenheit = (C x 1.8) + 32
Calcium Tablet Conversion
- Calcium Carbonate: 40% elemental
- Calcium acetate: 21% elemental
Calculating ANC

ANC = WBC X (segs + bands) / 100
Anion Gap equation
- Na - Cl - HCO₃
- *anion gap >12mEq/L considered high
Henderson hasslebalch
- pH = pka + log (base / acid)
- *ammonium is acidic
- weak acid: pH > pka
- weak base: pH < pka
- *pkw = pka + pkb: pkw = 14
Dilution and Concentration

Q1 X C1 = Q2 X C2
Drug-Nutrient interactions with enteral feedings
- warfarin
- tetracycline
- ciprofloxacin
- phenytoin
Percent Ionization

% ionization = 100 / 1+ 10^pka-pH
MWQ (minimum weighable quantity)
- ^{Mwq = SR (sensitivity requirement) / % of error}
- * change % to decimal first

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capnhue

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Updated

2014-07-28T20:20:50Z

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