Calculations Flashcards
Conversion of Aminophylline to Theophylline
Aminophylline x 0.8
Conversion of Theophylline to Aminophylline
Theophylline / 0.8
Shortcut for converting from PPM to a % strength
Move decimal left 4 places
Shortcut for converting % strength to PPM
Move decimal right 4 places
mOsmol/L =
Weight (g/L) / MW x # of particles x 1000
of dissociation particles in dextrose
1
of dissociation particles in mannitol
1
of dissociation particles in KCl
2
of dissociation particles in NaCl
2
of dissociation particles in sodium acetate (NaC2H3O2)
2
of dissociation particles in calcium chloride
3
of dissociation particles in sodium citrate (Na3C6H5O7)
4
E =
58.5i/MW(1.8)
mols =
g/MW
mmols =
mg/MW
mEq = (mg formula)
mg x valence / MW
mEq = (mmol formula)
mmols x valence
valence of ammonium chloride (NH4Cl)
1
valence of potassium chloride
1
valence of potassium gluconate (KC6H11O7)
1
valence of sodium acetate (NaC2H3O2)
1
valence of sodium bicarbonate (NaHCO3)
1
valence of sodium chloride
1
valence of calcium carbonate
2
valence of calcium chloride
2
valence of disodium phosphate
2
valence of ferrous sulfate
2
valence of magnesium sulfate
2
BMI = (metric)
kg/m^2
BMI = (US)
lbs/in^2 x 703
Use IBW for dosing which medications in normal and obese patients
aminophylline, theophylline and acyclovir
Use TBW for dosing which medications in obese patients
LMWHs, UFH, vancomycin
Use AbjBW for dosing which medications in obese patients
Aminoglycosides
Kcal/g for carbs in normal diet
4
Kcal/g for fat in normal diet
9
Kcal/g for protein in normal diet
4
kcal/g of dextrose monohydrate in PN
3.4
kcal/g of glycerol/glycerin in PN
4.3
kcal/ml in IVFE 10%
1.1
kcal/ml in IVFE 20%
2
kcal/ml in IVFE 30%
3
kcal/g in Amino acid solutions in PN
4
Fluid requirements weight >20 kg
1500 ml + 20 ml (weight in kg - 20)
Protein requirements for ambulatory, non-hospitalized (non-stressed) patietns
0.8-1 g/kg/day
Protein requirements for hospitalized or malnourished patients
1.2-2 g/kg/day
BEE (Harris Benedict Equation) for males
66.47 + 13.75 (kg) + 5(cm) - 6.76 (age)
BEE represents which calories
non-protein calories
BEE (Harris Benedict Equation) for females
655.1 + 9.6 (kg) + 1.85 (cm) - 4.68 (age)
TEE =
BEE x activity factor x stress factor
stress factor for minor surgery
1.2
stress factor for infection
1.4
stress factor for major trauma, sepsis, burns up to 30% BSA
1.5
stress factor for burns over 30% BSA
1.5-2
activity factor for non-ambulatory
1.2
activity factor for ambulatory
1.3
nitrogen intake =
grams protein / 6.25
desireable NPC:N for most severely stressed patients
80:1
desirable NPC:N for severely stressed patients
100:1
desirable NPC:N for unstressed patients
150:1
Maximum amount of dextrose in a PN
4 mg/kg/min or 7g/kg/day
Max lipids in a PN
2.5 g/kg/day
Ca corrected =
Ca reported + {(4-albumin) x 0.8]
Withhold which trace elements in severe liver disease
manganese and copper
withhold which trace elements in severe renal disease
chromium, molybdenum, and selenium
Warfarin and tube feed management
hold feeds for 1 hour before and 1 hour after
tetracycline and tube feed management
separate due to chelation
cipro and tube feed management
DO NOT USE SUSPENSION: USE IR TABLETS: flush with water before and after administration
Phenytoin and tube feed management
separate tube feeds by 2 hours
Normal blood pH
7.35-7.45
Anion gap =
Na - Cl - HCO3
pH > pKa means
more of the acid is ionized
pH = pKa means
the ionized and unionized forms are equal
pH
more of the acid is unionized
Henderson Hasselbalch for weak acids pH =
pKa + log [ salt/acid]
Henderson Hasselbalch for weak bases (pKb) pH =
14-pKb + log[base/salt]
Henderson Hasselbalch for weak bases (pKa) pH =
pKa + log [base/salt]
% elemental calcium in calcium carbonate
40%
% elemental calcium in calcium citrate
21%
ANC normal range
2000-8000 cells/microliter
ANC
predisposition to an infection
ANC
high risk for developing an infection
At what ANC can clozapine not be refilled
ANC
ANC =
WBC x (%segs + %bands/100)
