TEAM C SURVIVAL GUIDE: Answer to Question #2

2.  One of your fellow interns has a bad case of gastroenteritis and you have been dialed to the NICU.  One of your patients is a 500g five day old ex 24 week baby boy born to a G7P3Ab4 serology negative, GBS negative, HIV negative 20yo mother who had a positive urine toxicology screen for cocaine.  Your patient is ventilator dependent and has just completed a 48h course of Amp and Gent for a r/o sepsis evaluation.  This patient is on TPN of D7.5 P25 @ 2.8cc/h and IL @ 0.23cc/h.  You are just slightly overwhelmed, but know that in the morning, you will need to report P and F in g/kg/day, TF in cc/kg/day, and TC in kcal/kg/day and your patient’s GIR.  Get to work!

D7.5 P25 @2.8cc/h; IL @0.23cc/h; wt = 0.500kg

Proceed in any order you prefer, but follow all steps…
Also, be sure to check the day sheet to see what your patient actually received in the past 24 hours.

First, let’s calculate GIR. This is the formula:
GIR = % glucose x cc/h = mg/kg/min
6 (constant) x wt         

GIR = 7.5 x 2.8 = 7mg/kg/min
6 x 0.5           

Now let’s calculate the protein in g/kg/d:

Protein (g/kg/day) = (L/d) x (g/L)
                                 Wt (kg)
Convert units of known values to fit the above formula

2.8cc/h x 24h/d = 67.2cc/d

67.2cc/d x 1L/1000cc = 0.0672L/d

0.0672 L/d x 25 g/L = 3.36g/kg/d
0.5kg                    

Now calculate fat in g/kg/d:

g/kg/d = cc/d x 0.2g/cc
              wt(kg)

Convert units of known values to fit the above formula

0.23cc/h x 24h/d = 5.52cc/d

5.52 x 0.2 = 2.2g/kg/d
0.5kg                

To calculate the total calories (TC):

Protein = 3.4g/kg/day x 4kcal/g = 13.6 kcal/kg/day of protein

Dextrose:
D7.5% @2.8cc/h

2.8cc/h x24h/day=67.2cc/d

D7.5% =7.5g/100cc

7.5g/100cc x 67.2cc/day = 5g/day 

5 g/day x 3.4 kcal/g = 17 kcal/day 

Divide by the weight:

17kcal/day ÷ 0.5kg = 34.3 kcal/kg/day of dextrose

Fat = 0.23cc/h 

0.23cc/h x 24h/day = 5.52cc/day

Use formula of 2.2Kcal/cc in 20%IL:

5.52cc/day x 2.2kcal/cc = 43.8kcal/day

Divide by the weight:
43.8kcal/day ÷ 2kg = 24.3kcal/kg/day of fat

Now add them up for your total kcal/kg/day:

Dextrose + Protein + Fat = Total calories

34.3 + 13.6 + 24.3= ~72kcal/kg/day

TC = 72kcal/kg/day

Now calculate total fluid by adding total cc/d including the TPN bag of D+P and that of fat:

 67.2cc/d + 5.52cc/d = 72.7

divide by weight:

72.7cc/d ÷ 0.5kg = 145cc/kg/d

TF = 145cc/kg/d

On rounds in the morning, you can report that your patient is on D7.5 P25 @2.8cc/h; IL 0.23cc/h for P3.4 F2.2 and GIR of 7.  TF=145   TC= 72