Tube feeding nursing calculations review for students!
This review will demonstrate how to solve tube feeding calculations that require you to solve for dilution based on feeding strength, total volume, and administration time.
What is a tube feeding? Just as the name says, it is a way to deliver nutrition to a patient via a tube. It can be performed various ways:
Nasogastric tube (this is inserted through the nose, down the throat, and into the stomach)
PEG tube (a surgical incision is made through the skin and a tube is inserted through the skin and into the stomach)
Before solving tube feeding calculations, specifically problems that require you to solve for dilution amount and total volume, you want to commit to memory the following formula:
mL in formula can = Strength ordered
X
Lecture on Tube Feeding Nursing Calculations
Tube Feeding Practice Problems
Problem 1:
The patient is ordered Jevity 1.2 cal. You’re supplied with a can of Jevity that contains 237 mL of formula. The doctor orders the tube feeding to be administered at 1/2 strength at a rate of 60 mL/hr. What is the total volume of formula that will be administered?
First, determine the important information you need to solve this problem:
- What is it asking you to solve? Total volume of formula to be administered
- Information you need to answer the question?
- Can amount: 237 mL
- Strength ordered: ½
Use the formula above to solve:
237 mL = 1
X 2 (*multiply the values across from one another)
474 mL = 1 x
474 mL = 1 x
1 1 (*solve for “x”, which will tell you the total volume, by dividing each side by 1)
474 mL = x (total volume)
Problem 2:
The patient is ordered Jevity 1.2 cal. You’re supplied with a can of Jevity that contains 237 mL of formula. The doctor orders the tube feeding to be administered at 1/2 strength at a rate of 60 mL/hr. How much water will you add to dilute the tube feeding formula as prescribed?
First, determine the important information you need to solve this problem:
- What is it asking you to solve? Amount of water added to dilute tube feeding
- Information you need to answer the question?
- Can amount: 237 mL
- Strength ordered: ½
Use the formula above to solve:
237 mL = 1
X 2 (*multiply the values across from one another)
474 mL = 1 x
474 mL = 1 x
1 1 (*solve for “x”, which will tell you the total volume, by dividing each side by 1)
474 mL = x (total volume)
474 mL (total volume) – 237 mL ( amount in formula can) = 237 mL of water added for dilution
Problem 3:
The patient is ordered Glucerna 1.5 cal. You’re supplied with a can of Glucerna that contains 237 mL of formula. The doctor orders the tube feeding to be administered at 1/4 strength at a rate of 50 mL/hr. How much water will you add to dilute the tube feeding formula as prescribed?
First, determine the important information you need to solve this problem:
- What is it asking you to solve? Amount of water added to dilute tube feeding
- Information you need to answer the question?
- Can amount: 237 mL
- Strength ordered: 1/4
Use the formula above to solve:
237 mL = 1
X 4 (*multiply the values across from one another)
948 mL = 1 x
948 mL = 1 x
1 1 (*solve for “x”, which will tell you the total volume, by dividing each side by 1)
948 mL = x (total volume)
948 mL (total volume) – 237 mL (amount in formula can) = 711 mL of water added for dilution
Problem 4:
The MD orders Glucerna via the patient’s nasogastric tube. The formula is to be administered at 3/4 strength at a rate of 60 mL/hr. You’re supplied with a can of Glucerna that contains 237 mL. How long will it take to administer this tube feeding formula?
First, determine the important information you need to solve this problem:
- What is it asking you to solve? Time it will take to administer the tube feeding formula
- Information you need to answer the question?
- Can amount: 237 mL
- Strength ordered: 3/4
- Rate: 60 mL/hr
Note: This will be a two-step problem because FIRST we need to solve for the total volume, and then use that answer to calculate the administration time based on the prescribed rated.
Use the formula above to solve:
First step: solve for the total volume to be administered
237 mL = 3
X 4 (*multiply the values across from one another)
948 mL = 3 x
948 mL = 3 x
3 3 (*solve for “x”, which will tell you the total volume, by dividing each side by 3)
316 mL = x (total volume)
Second step: solve for the administration time since we now know the total volume to be administered (316 mL). We need the prescribed rate to helps us do that: 60 mL/hr
316 mL x 1 hr = 316 = 5.266666 = 5.27 hrs (*convert the left over hours (0.27) to minutes)
1 60 mL 60
0.27 hr x 60 min = 16.2 minutes
1 1 hr
Answer: 5 hrs 16 minutes
Test your knowledge with this tube feeding practice questions quiz.