Total parenteral nutrition (TPN) provides complete nutrition to patients who cannot eat or absorb enough nutrients from food. Candidates for TPN include those with gastrointestinal obstructions or surgeries, cancers, inflammatory bowel disease, or significant involuntary weight loss. Initial assessment involves labs, physical exam, and medical history. TPN provides calories, protein, electrolytes, vitamins, and minerals in calculated amounts based on patient characteristics. Close monitoring of labs and the patient is required to watch for complications like refeeding syndrome, electrolyte imbalances, and infections. TPN is discontinued as the gastrointestinal system recovers and oral/enteral intake can meet nutritional needs.

1. GOD

2. Total Parenteral
Nutrition
Andisheh. Maneshi
Resident of pharmacotherapy
Tehran University of Medical
Sciences

3. Candidates for Receiving TPN
O obstruction in GI tract
O Surgery, trauma
O Chemotherapy, radiation therapy
O GI cancers
O IBD
O surgery or procedure requiring to be NPO (3-5
days…..7)
O Loss of appetite or no oral intake for past 5 days
O Absorption impairment
O Involuntary weight loss of ≥ 10% within last 3-6 months

4. Initial Patient Assessment
O Lab checks
O Physical assessment
O Nutritional history
O Consideration of other diseases
o Renal
o Hepatic
o Respiratory
o Cardiac
o metabolic

5. Lab Values
O Electrolytes
Na, K, Cl, Acetate, Phos, Mg, Ca
O Renal function evaluation
SrCr, BUN, urine output
O Liver function evaluation
ALT, AST, Alk Phos, Bili
O Protein status
Albumin, total protein, pre-albumin
O Lipid profile

6. Monitoring
O Daily lab values to be checked
Na, K, Cl, acetate, SrCr, FBS
O Twice weekly labs
Mg, Phos, Ca, CBC
O Weekly labs:
Albumin, LFTs, TG, INR
 Daily:
O in/out
O Pt’s weight
O IV site check for possible infection
O Checked of drug added to the regimen for possible physical
incompatibilities & interactions
Glucose to be checked every six hours and SSI

7. Calculations
OVolume : 40-60 cc/kg, More in N/V, Diarrhea, fever
OEnergy (Calorie): 20 -35 kcal/kg
OProtein: 0.6-2 g/kg/day
Oelectrolytes
O vitamins
Otrace elements

8. Calculations
Protein
O Calculation is based on:
O Renal function (max:1g/kg)
O Hepatic function(0.6 – 0.8 g/kg)
0.6-2 g/kg/day

9. Example
O Woman, 35Y/o, IBD, Diarhea, fistule, weight loss,
3lit 1/3,2/3
1. Cv Line (osmolarity)
2. V: 3lit
3. Calories:30kcal/kg/d= 1800cal (CHO, IL10%,
IL20%)
4. AA:2g/kg/d (10% (50/500cc), 5%(25/500cc)): 120g
70% CHO+30%li
Goal:
CHO:1800*2/3=1200/3.4=353g
IL: 1800*1/3=600/1.1=545 cc

10. Calculations: electrolytes
O Sodium: (135-145)1-2meq/kg/d
O Potassium:(3.5-5)1-2meq/kg/d
O Magnesium:(1.5-2.4) 8-20meq/d
O Phosphate:(2.5-4.5) 15-40 mmol/d
O Calcium: corrected with Alb
5-15meq/d
KCl 15% inj: 2meq/ml
NaCl 5% inj :0.86meq/ml
MgSO4 50% inj: 4meq/ml
CaGluconate 10% inj: 0.5meq/ml
NaPhos inj: 1mmmol ph, 2meq Na/m
1. NS
2. ½ NS
3. D5W
4. D10W
5. 1/3 ,2/3
6. D5/NS

11. O TPN: 24h(ideal)
Hyperglycemia, Tachycardia, ….
O Intralipead : 12h (infection)

12. Calculations
insulin
ORegular insulin :
OInsulin used in the previous day as SSI
(a fraction of ins added to next day
TPN)
OBased on grams of dextrose in the
solution

13. Calculations
vitamins
O B vitamins
O Ascorbic acid (Vit C)
O Vitamin A
O Vitamin D
O Vitamin E
O Vitamin K
 Soluvit
 Bcomplex

14. Calculations
trace elements
OCopper
OManganese
OSelenium
OZinc
OChromium
Adamel
Tracutil

15. TPN therapy complications
O Re-feeding syndrome :
Intracellular electrolyte shift
O hypoMg, hypoK, hypoPhos
O Hyperglycemia, hyper insulinemia
O Prevention:
start TPN with 50% of energy requirements for the 1st 2
days
O Electrolyte imbalance
O IV line infection/ bacteremia

16. Discontinuation of TPN
O As soon as GI is functional considering D/C process
O Titrate the TPN rate down by increasing the oral or
enteral feeding tolerance
O May use cyclic TPN for a few days before D/C or in
cases of long TPN therapy