Question

Using the Harris-Benedict equation, calculate the TPN caloric requirement for a hospitalized, bedridden, 60-year-old male surgical patient, weighing 160 lb, and measuring 5 ft 8 in. in height. (activity factor (Bed ridden)- 1.2, Stress factor (surgical)- 1.2

Answer 1

Let me give you some introduction to the equations that we have to know inorder to solve these questions.

Basal Energy Expenditure (BEE) by Harris Benedict equation .

We have separate equations for male and female.Here the patient is male and hence,

BEE for male is given by the equation,

BEE= 66.67 + (13.75 x kg) + (5 x cm) - (6.76 x age)

Also,Totoal daily energy Requirement

TDE = BEE x activity factor x stress factor

So,now we can solve the question.
In all questions which requires some equation to solve ,we have to note whether the units given in the equation and question are same or not.

So,here the weight has to be in kg ,height in cm and age in years .

So first ,we can change the given values to standard units.

Weight of the patient = 160 lbs
1 lbs = 0.454 kg
So 160 lbs =160×0.454= 72.5kg

Height of the patient is = 5ft 8 inch
1 ft =30 cm
So 5 ft =5×30=150 cm
1 inch = 2.5cm
8 inch =2.5×8=20 cm
So, patient height is 150+20= 170 cm .

Now we can substitute the values to the equation to get the calorie required for TPN ( total parenteral nutrition)

BEE= 66.67 + (13.75 x kg) + (5 x cm) - (6.76 x age)

=66.67+(13.75×72 .5)+(5×170)-(6.76×60)
=66.7+996+850-405
=1507 kcalories

Now, TDE =BEE ×stress factor× activity factor

TDE= 1507×1.2×1.2
=2170 kcalories

So the patient would need 2170 kcalories as total parenteral nutrition.