MUST KNOW FORMULAS Flashcards

1
Q

how many mL in 1 tsp

A

5mL

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

how many mL in 1 tbsp

A

15mL

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

how many mL in 1 fl oz

A

30 mL (approx), 29.57 mL (actual)

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

how many oz & mL in 1 cup

A

8 oz = 240 mL (approx), 236.56 mL (actual)

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

how many oz & mL in 1 pint

A

16 oz = 480 mL (approx), 473 mL (actual)

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

how many mL in 1 quart

A

2 pints = 960 mL (approx), 946 mL (actual)

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

how many mL in 1 gallon

A

4 quarts = 3840 mL approx), 3785 mL (actual)

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

how many pounds in 1 kg

A

2.2 lb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

how many grams in 1 oz

A

28.4 g

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

how many grams in 1 pound

A

454 g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how many mg in 1 grain

A

65 mg (approx), 64.8 (actual)

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

mEq to mmol for monovalent ions

A

1:1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

mEq to mmol for divalent ions

A

1:0.5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how many cm in 1 in

A

2.54 cm

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

how many cm in 1 m

A

100 cm

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

CBC fish bone diagram

A

going zigzag left to right: WBC, Hgb, Hct, Plt

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

BMP fish bone diagram

A

going zigzag left to right: Na, K, Cl, HCO3, BUN, SCr, Glucose

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

%w/v

A

X g / 100mL

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

%v/v

A

X mL / 100mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

%w/w

A

X g / 100g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

percentage strength formula

A

percentage strength = 100 / ratio strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

ratio strength formula

A

ratio strength = 100 / percentage strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

PPM to percentage strength formula

A

move decimal left 4 places

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

percentage strength to PPM formula

A

move decimal right 4 places

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

specific gravity formula

A

SG = weight of substance (g) / weight of equal volume of water (g)

SG = g/mL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

dilution & concentration formula

A
  • for changing strength or quantity

Q1C1 = Q2C2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

alligation formula

A

*use proportions to calculate amount of high% and/or low% required

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

osmolarity formula

A

mOSmol/L = [weight of substance (g/L) / MW (g/mole) ] * (# of particles) * 1000

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

isotonicity formula

A

E = [(58.5) * (i) ] / [(MW of drug)*(1.8)]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

moles formula

A

mols = g / MW

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

millimoles formula

A

mmol = mg / MW

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

milliequivalents formula

A

mEq = (mg * valence) / MW

mEq = mmols * valence

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

enteral nutrition calories for protein

A

4 kcal/g

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

enteral nutrition calories for carbs

A

4 kcal/g

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

enteral nutrition calories for fats

A

9 kcal/g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

parenteral nutrition calories for proteins

A

4 kcal/g

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

parenteral nutrition calories for dextrose

A

3.4 kcal/g

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

parenteral nutrition calories for lipids

A

ILE 10% = 1.1 kcal/mL
ILE 20% = 2 kcal/mL
ILE 30% = 3 kcal/mL

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

determining fluid needs formula

A

when weight >20kg: 1500mL + (20mL)(weight in kg - 20)

*can estimate using 30-40 mL/kg/day (TBW)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

total energy expenditure formula

A

TEE = BEE * activity factor * stress factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

grams of nitrogen from protein

A

nitrogen (g) = protein intake (g) / 6.25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

corrected calcium for albumin <3.5

A

*not needed for ionized Ca
Ca corrected (mg/dL) = serum Ca + 0.8(4 - albumin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

BMI formula

A

BMI (kg/m2) = weight (kg) / [height (m)]^2

BMI = [weight (lbs)] / [height (in)]^2] * 703

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

underweight BMI

A

<18

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

normal BMI

A

18.5-24.9

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

overweight BMI

A

25-29.9

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

obese BMI

A

≥30

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

IBW formula

A

IBW (males) = 50kg + 2.3(# in >5 ft)
IBW (females) = 45.5kg + 2.3(# in >5 ft)

49
Q

adjusted body weight formula

A

AdjBW = IBW + 0.4(TBW-IBW)

50
Q

weight to use for all drugs (if underweight)

A

TBW

51
Q

weight to use for most drugs (if normal weight or obese)

A

TBW

*LMWH, UFH, vanco

52
Q

weight to use for acyclovir, aminophylline, levothyroxine

A

IBW

53
Q

weight to use for theophylline (normal weight, obese)

A

IBW

54
Q

weight to use for AMGs (obese)

A

AdjBW

55
Q

flow rates/drop factor (drops/min) formula

A

(#drops/mL) * (mL/hr) * (hr/60 min) = #drops/min

56
Q

dehydration formula

A

BUN:SCR >20:1

57
Q

cockcroft-gault equation

A

CrCl (mL/min) = [[(140-age) * weight (kg)] / (72 * SCr)]

  • x0.85 if female
58
Q

ABG formula

A

ABG: pH/pCO2/pO2/HCO3/O2 sat

59
Q

steps to determining acidosis/alkalosis

A
  1. pH <7.35 = acidosis & pH >7.45 = alkalosis
  2. respiratory: pCO2 <35 = alkalosis & pCO2 >45 = acidosis || metabolic: HCO3 >26 = alkalosis, HCO3 <22 = acidosis
  3. look at abnormalities & determine
60
Q

anion gap formula

A

AG = Na - Cl - HCO3

61
Q

weak acid formula

A

pH = pKa + log[salt/acid]

62
Q

weak base formula

A

pH = pKa + log[base/salt]

63
Q

weak acid percent ionization

A

% ionization = 100 / [1 + 10^(pKa-pH)]

64
Q

weak base percent ionization

A

% ionization = 100 / [1 + 10^(pH-pKa)]

65
Q

ANC formula

A

ANC (cells/mm3) = WBC * [(%segs + %bands)/100]

66
Q

neutropenia classification

A

2200-8000 = normal
<1000 = neutropenia
<500 = severe
<100 = profound

67
Q

F to C formula

A

C = (F - 32) / 1.8

68
Q

C to F formula

A

F = (C * 1.8) + 32

69
Q

time to burn formula

A

TTB (with sunscreen in min_ = SPF * TTB (without sunscreen)

70
Q

how much elemental calcium in calcium carbonate?

A

40% elemental calcium

71
Q

how much elemental calcium in calcium citrate

A

21% elemental calcium

72
Q

how much elemental calcium in calcium acetate

A

25% elemental Ca
*used as phosphate binder, not Ca supplementation

73
Q

mean

A

average value

74
Q

median

A

value in the middle of an ordered list

75
Q

mode

A

value that occurs most frequently

76
Q

risk formula

A

risk = # subjects in group w/ unfavorable event / total # subjects

77
Q

relative risk formula

A

RR = risk in treatment group / risk in control group

78
Q

relative risk reduction formula

A

RRR = (%risk in control group - %risk in treatment group) / %risk in control group

79
Q

absolute risk reduction formula

A

ARR = (%risk in control group ) - (%risk in treatment group)

80
Q

number needed to treat formula

A

NNT = 1 / ARR (decimal)
*ALWAYS ROUND UP

81
Q

number needed to harm formula

A

NNH = 1 / ARR (decimal)
*ALWAYS ROUND DOWN

82
Q

odds ratio formula

A

OR = AD/BC

A = outcome present & exposure present
B = outcome absent * exposure present
C = outcome present & exposure absent
D = outcome absent & exposure absent

83
Q

hazard ratio formula

A

HR = hazard rate in treatment group / hazard rate in control group

84
Q

incremental cost-effective ratio

A

ICR = (C2 - C1) / (E2 - E1)

C = costs
E = effects

85
Q

pack year smoking history formula

A

pack-year smoking history = cig packs/day * years smoked

86
Q

how to initiate basal-bolus insulin in type 1 diabetes

A
  1. calculate TDD of 0.5 units/kg/day with TBW
  2. divide into 1/2 basal & 1/2 rapid acting; if using NPH/R, use 2/3 & 1/3
  3. split rapid-acting among meals
87
Q

which rules do we use for regular insulin

A

ICR rule of 450
CF rule of 1500

88
Q

which rules do we use for rapid-acting insulin

A

ICR rule of 500
CF rule of 1800

89
Q

insulin-to-carb ratio: rule of 450 formula

A

450 / TDD = grams of carb covered by 1 unit of REGULAR insulin

90
Q

insulin-to-carb ratio: rule of 500 formula

A

500 / TDD = grams of carb covered by 1 unit of RAPID-ACTING insulin

91
Q

correction factor: 1500 rule

A

1500 / TDD = correction factor for 1 unit of REGULAR insulin

92
Q

correction factor: 1800 rule

A

1800 / TDD = correction factor for 1 unit of RAPID-ACTING insulin

93
Q

correction dose formula

A

(current BG - target BG) / correction factor = correction dose

94
Q

friedewald equation

A

LDL = TC - HDL - (TG/5)

  • DNU if TG >400!!
95
Q

minimum weighable quantity formula

A

MWQ = sensitivity requirement / acceptable error rate (usually 0.05)

96
Q

Mosteller BSA formula

A

BSA (m2) = sqrt [(ht in cm * wt in kg) / 3600]

97
Q

bioavailability formula

A

F(%) = 100 * (AUCextravascular / AUCintravenous) * (Doseintravenous / Doseextravascular)

98
Q

volume of distribution formula

A

Vd = amount of drug in body / concentration of drug in plasma

99
Q

clearance formula

A

Cl = (F * dose) / AUC

Cl = ke * Vd

100
Q

elimination rate constant formula

A

ke = Cl / Vd

101
Q

predicting drug concs formula

A

C2 = C1 * e^(-kt)

ke = [ln (C1/C2)] / t

102
Q

half-life formula

A

t1/2 = 0.693 / Ke

103
Q

loading dose formula

A

LD = (desired concentration * Vd) / F

104
Q

mean arterial pressure

A

MAP = [(2 * DBP) + SBP] / 3

105
Q

phenytoin correction formula for albumin <3.5

A

corrected PHT (mcg/mL) = serum PHT / [(0.2 * albumin) + 0.1]

106
Q

conversion of KCl PO sol to tabs

A

KCl 10% = 20 mEq/15 mL

107
Q

conversion of aminophylline to theophylline

A

A * 0.8 = T

108
Q

conversions of statins

A

pitavastatin 2mg
rosuvastatin 5mg
atorvastatin 10mg
simvastatin 20mg
lovastatin 40mg
pravastatin 40mg
fluvastatin 80mg

109
Q

opioid conversions

A

morphine: 10mg (IV) = 30mg (PO)
hydromorphone: 1.5mg (IV) = 7.5mg (PO)
oxydocone: no IV = 20mg (PO)

110
Q

IV to PO - metoprolol

A

IV:PO = 1:2.5

111
Q

conversions of loop diuretics

A

ethacrynic acid 50mg
furosemide 40mg
torsemide 20mg
bumetanide 1mg

112
Q

IV to PO - furosemide

A

IV:PO = 1:2

113
Q

IV to PO - other loop diuretics

A

IV:PO = 1:1

114
Q

how much elemental iron is in ferrous sulfate

A

20% elemental iron

115
Q

conversion of insulins

A

usually 1:1
NPH BID -> glargine QD = use 80% of NPH dose
toujeo -> other glargine or detemir = use 80% of Toujeo dose

116
Q

IV to PO - levothyroxine

A

IV:PO = 0.75:1

117
Q

conversion of steroids

A

cortisone 25mg
hydrocortisone 20mg
prednisone 5mg
prednisolone 5mg
methylprednisolone 4mg
triamcinolone 4mg
dexamethasone 0.75mg
betamethasone 0.6mg

118
Q

conversion of lithium

A

5mL lithium citrate syrup = 300mg lithium carbonate = 8mEq Li+ ion

119
Q

age classification

A

neonate = 0-28 days
infant = 1-12 months
toddler = 1-2 years
child = 2-12 years
adolescent = 13-18 years