Anesthesia Math

Question 1

Convert lbs to kg, and kg to lbs
200lb to kg
70kg to lb

Answer 1

Lb/2 - 10% = 90kg

Kg x 2.2 = 154lbs

Question 2

Calculate BMI
154 lb
5’ 8”

Answer 2

BMI = kg/M^2
154lb/2 =77-7(about 10% of 77)= 70kg
5x12in +8 equals 68 inches. 68 inches multiplied 0.0254 m= 1.72

BMI = 70kg / (1.72m)^2 = 23.4 kg/m^2

Question 3

Decimal to percent / percent to decimal
0.28 to %
67% to decimal

Answer 3

Dec to per move two RIGHT
Per to decimal two LEFT
28%
0.67

Question 4

Mcg to mg to g
Mcg to g

1000000 mcg to g

Answer 4

1000mcg per mg
1000 mg per g
1000000mcg per g

So 1g = 1000000 mcg

Question 5

Key to dosing in tenths

Answer 5

simply

figure out how many mg (or mcg) are in 1/10th of a mL

Question 6

• To convert a percentage
concentration to mg/mL,
________________________
– 0.1% = ___mg/mL – 1% = ___mg/mL – 10% = ___mg/mL – 100% = ___mg/mL

Answer 6

multiply the percentage by 10

1, 10, 100, 1000

Question 7

To convert a mg /mL
concentration to a percentage,
___________________________
– 50mg/mL = ___% – 0.4mg/mL = ___% – 0.08mg/mL = ___%

Answer 7

divide the mg/mL concentration
by 10
– 50mg/mL = 5\_\_\_%
 – 0.4mg/mL = _.04\_\_% 
– 0.08mg/mL = \_\_.008_%

Question 8

Key to drug dilution

Answer 8

simply ask
ourselves how many TOTAL mg (or mcg) need to go into the
syringe (or bag).

Question 9

Adding Mg To A 250mL Bag of Fluid trick

Answer 9

• When you add a certain number of mg to 250mL,
the final concentration in mcg is 4x the amount of
mg that were added
–

• For example
– 4mg in 250mL = 16mcg/mL
– 10mg in 250mL = 40mcg/mL
– 20mg in 250mL = 80mcg/mL 250mL N/S bag

Question 10

Epi Concentrations are expressed as ratios or percents?

Answer 10

• Expressed as a ratio (numerator and denominator);
NOT as a percentage
– Example: 10mcg/mL
• Expressed as 1:100,000
• NOT expressed as 0.001%

• Numerator= Always 1 gram (1,000,000mcg) of epi
• Denominator =This is the volume that the 1 gram of epi is dissolved in