Fluids, Electrolytes, Acid-Base Disorders, and Nutrition Support

problem (overfeeding) and are inappropriate manage-

ment techniques.

Total kilocalories per day = (300 g x 3.4 kcal/g of dex-

trose) + (70 g x 4 kcal/g of protein) + (40 x 10 kcal/g of

lipid emulsion) = 1020 glucose kcal + 280 protein kcal +

400 lipid kcal = 1700 total kcal/65 kg = 26 kcal/kg/day.

Only 20% and 30% lipid emulsions are available for

PN compounding. Each solution provides 10 kcal/g of

intravenous lipid (unlike 9 kcal/g with oral fat) because

glycerol and phospholipids are added to the emulsion.

Protein intake is 70 g/65 kg = 1.1 g/kg/day (Answer A is

correct). Answers B, C, and D do not represent the cor-

rect calculations as described previously.

This patient is moderately stressed with a normal BMI.

Appropriate energy intake would be 25–30 kcal/kg/day

(1625–1950 kcal/day), and protein intake would be 1.2–2

g/kg/day (78–130 g). Increasing dextrose to 400 g/day

would provide a total energy of 31 kcal/kg/day. Although

this glucose intake of 4.3 mg/kg/minute does not exceed

5 mg/kg/minute, the total kcal/day from all macronu-

trients would exceed the recommended initial range for

this patient (Answer A is incorrect). Decreasing the dex-

trose dose to 200 g/day would provide a total energy of

21 kcal/kg/day from all macronutrients, which is below

the target energy range for this patient (Answer B is

incorrect). Increasing the lipid dose to 70 g/day would

provide a total energy of 31 kcal/kg/day from all mac-

ronutrients, which is above the target of 25–30 kcal/kg/

day (Answer D is incorrect). A protein dose of 100 g/

day would provide 1.5 g/kg/day of protein. This dose is

appropriate and falls within the recommended 1.2–2 g/

kg/day. Increasing the protein dose to 100 g/day while

maintaining dextrose at 300 g and lipid at 40 g would

provide the patient with 1820 kcal or 28 kcal/kg/day.

This is an appropriate protein and energy intake for this

patient (Answer C is correct).

Because the target BG should be within 140–180 mg/dL

for this surgical patient being transferred to the floor, a

modest improvement in glycemic control is indicated.

Thus, answer D (no change) would be incorrect. Ideally,

obligatory glucose requirements should be met (e.g.,

about 130 g/day plus about 80–150 g/day for wound

healing) to prevent the use of amino acids for gluconeo-

genesis. Thus, decreasing the glucose intake to 100 g/

day as described in answer B is not desirable, given the

mild increases in BG concentration. The easiest method

to achieve glycemic control and meet caloric needs is to

modestly increase the regular human insulin content in

the PN solution. Because 14 units of sliding scale insulin

still appears insufficient, a modest increase in insulin

appears prudent. The patient is unlikely to experience

hypoglycemia with the provision of insulin at 30 units/

day when given 200 g of intravenous dextrose concur-

rently (Answer A is correct). As the stress resolves and

glycemic control improves, insulin can be decreased or

eliminated from the PN solution. Answer C is incorrect

because it would likely provide too much insulin, based

on sliding scale coverage and current BG range, and

increase the patient’s risk for hypoglycemia.