Intake Fluid Measurement – converting ounces to milliliters (mL) or cubic
centimenters (cc)
In giving nursing care, nursing assistants need to report the amount of fluids
patients drink/take in daily. For minimal body functioning, adults need at least
1,500 mL of liquids to survive. However for normal fluid balance, adults need
2,000 to 2,500 mL. So, accurately reporting patients’ daily fluid intake, as well as
encouraging patients to drink fluids to meet daily needs is a very important part
of nursing care.
In order to report fluid intake accurately, it is important to know the following:
1 cup = 8 ounces (oz.)
The formula for converting ounces to mL or cc is:
number of oz. x 30 = measurement in mL or cc
1 cup = 240 mL because 8 oz. x 30 = 240
Convert the following to mL:
a. 3 oz. =
b. 5 oz. =
c. 16 oz. =
 Sometimes, you will be reporting fractional parts of cups like 1 ¼ cups. You
can convert the cups to ounces and then mL by:
Multiplying the cup measurement x 8 oz to get the ounces measurement
Then multiply the cup oz. x 30.
Or, you can simply multiply the cup measurement x 240. So 1 ¼ cups x 240
To convert 1 ¼ cups to mL,
1. 1 ¼ x 8 = 10 oz.
2. 10 oz. x 30 =300 mL
or
1 ¼ x 240 = 300
Let’s try converting the following to mL:
a.
b.
c.
d.
e.
f.
g.
2 cups =
1 ½ cups =
2 ¾ cups =
6 oz. =
2 1/3 cups =
4 oz. =
11 oz. =
Application Problems:
How are the following patients doing with their daily intake of fluids? Since 2,000
mL of fluid are needed daily for normal body functions, first determine how
many mL each patient has consumed so far today. Identify which patients need
to be encouraged to consume more fluids to meet the 2,000 mL intake standard.
a. Mrs. Anderson has consumed the following fluids today:
6 oz. orange juice
1 cup coffee
1 ¾ cups broth
12 oz. water
1 cup tea
¾ cup apple juice
TOTAL mL =
Does Mrs. Anderson need more fluids today?
b. Mr. Cerna has consumed the following fluids today:
2 cups coffee
24 oz. water
2 ½ cups chicken noodle soup
16 oz. 7-up
2 6oz. glasses milk
12 oz. iced tea
TOTAL mL =
Does Mr. Cerna need more fluids today?
c. Mrs. Adams is on fluid restrictions because she has congestive heart failure.
She is allowed not more than 1,500 mL fluids daily. As a nursing assistant
you will not leave a pitcher of water in her room. You will be bringing fluids
to her room on her meal trays. So far today, this is what she has
consumed:
cereal with 6 oz. milk
1 cup tea
2 cups water
1 cup apple juice
1 cup broth
½ cup coffee
TOTAL mL
Is Mrs. Adams allowed more fluids today?
d. Calculate your fluid intake in mL so far today.