Total Parenteral (TPN) Nutrition

By: E. Salehifar (Clinical Pharmacist)

Malnutrition

  

Incidence:

50 % of hospitalized patients

Common causes:

- Hypermetabolic states: Trauma, Infection, Major surgery, Burn - Poor nutrition

Consequences:

Weakness, Decreased wound healing, increased respiratory failure, decreased cardiac contractility, infections (pneumonia, abscesses), Prolonged hospitalization

Nutritional Support

 Enteral Nutrition ( Physiologic, less expensive)  Parenteral Nutrition - GI should not be used (Obstruction, Pancraitis) - GI can not be used ( Vomiting, Diarrhea, Resection of intestine, IBD)

Parenteral Nutrition

  Peripheral Parenteral Nutrition (15 lit D5W/day for a 70 kg !!!) Central Parenteral Nutrition (TPN)  Needs CV-line to administer hyperosmolar solutions

Estimation of energy expenditure

    

Harris-Benedict equations:

BEE (men) (kcal/day): 66.47+13.75W+5H-6.76A BEE (women) (kcal/day): 655.1+9.56W+1.85H-4.68A TEE (kcal/day):

BEE × Stress factor × Activity factor

Stress factors: Surgery, Infection: 1.2 Trauma: 1.5 Sepsis: 1.6 Burns: 1.6-2 Activity factors: sedentary: 1.2 , normal activity: 1.3, active: 1.4 , very active: 1.5

Stress level

 Normal/mild stress level: 20-25 kcal/kg/day  Moderate stress level: 25-30 kcal/kg/day  Severe stress level: 30-40 kcal/kg/day  Pregnant women in second or third trimester: Add an additional 300 kcal/day

 30-40 mL/kg

Fluid: mL/day

Protein (amino acids)

 Maintenance: 0.8-1 g/kg/day  Normal/mild stress level: 1-1.2 g/kg/day  Moderate stress level: 1.2-1.5 g/kg/day  Severe stress level: 1.5-2 g/kg/day  Burn patients (severe): Increase protein until significant wound healing achieved  Solid organ transplant: Perioperative: 1.5-2 g/kg/day

Protein need in Renal failure

 Acute (severely malnourished or hypercatabolic): 1.5-1.8 g/kg/day  Chronic, with dialysis: 1.2-1.3 g/kg/day  Chronic, without dialysis: 0.6-0.8 g/kg/day  Continuous hemofiltration: ≥ 1 g/kg/day

Protein need in Hepatic failure

 Acute failed: management when other treatments have  With encephalopathy: 0.6-1 g/kg/day  Without encephalopathy: 1-1.5 g/kg/day  Chronic encephalopathy  Use branch chain amino acid enriched diets only if unresponsive to pharmacotherapy  Pregnant women in second or third trimester  Add an additional 10-14 g/day

Fat

 Initial: 20% to 40 % of total calories (maximum: 60% of total calories or 2.5 g/kg/day)  Note: Monitor triglycerides while receiving intralipids.

 Safe for use in pregnancy  I.V. lipids are safe in adults with pancreatitis if triglyceride levels <400 mg/dL

Components of TPN Formulations

Macro: Calorie: Protein: Micro:

Dextrose 20%, 50% Intralipid 10%, 20% Aminofusion 5%, 10% Electrolytes (Na, K, Mg, Ca, PO4) Trace elements (Zn, Cu, Cr, Mn, Se)

Dextrose

 20%, 50% ( from CV-line)  3.4 kcal/g  60-70% of calorie requirements should be provided with dextrose

D20W D30W D40W

For 1000 ml solution

D50W

250 ml

D10W

750 ml

D5W

----- 333 ml 500 ml 555 ml 750 ml 778 ml ----- 500 ml ---- 250ml ----- 667 ml ----- 446 ml ----- 222 ml

Dextrose: Contraindications

 Hypersensitivity to corn or corn products  Hypertonic solutions in patients with intracranial or intraspinal hemorrhage

Abrupt withdrawal

 Infuse 10% dextrose at same rate and monitor blood glucose for hypoglycemia

Intralipid

 10%, 20% ( from peripheral or CV-line)  1.1 kcal/ml (10%), 2 kcal/ml (20%)  30-40% of calorie requirements should be provided with Intralipid

1022 Kcal/L 345 mosmol/L 1080 Kcal/L

Intralipid: Contraindication

 Hypersensitivity to fat emulsion or any component of the formulation; severe egg or legume (soybean) allergies  Pathologic hyperlipidemia, lipoid nephrosis, pancreatitis with hyperlipemia (TG>400 mg/dl)

Aminofusion



5%, 10% ( from CV-line)



1-1.5 g/kg/day



Should not be used as a calorie source

400 Kcal/L 1030 mosmol/L 200 kcal/L 590 mosmol/L

Amino acids: Contraindications

 Hypersensitivity to one or more amino acids  Severe liver disease or hepatic coma

Case

 D.C a 38 y.o man with a

12-year history of crohn’s disease

is admitted to surgery ward of Imam hospital in Sari for a compliant of increasing abdominal pain,

for 7 days nausea & vomiting

and no stool output for 5 days. Because of N & V, he has been drinking only liquids during the past weeks. His crohn disease had several exacerbations during the past 2 years and

10 cm of his ileum has been resected

month ago.

6

case (continue)

Drugs: Mesalamine 1000 mg qid + prednisolone 10mg/d. Abdominal x-ray is consisting with

bowel obstruction

. Exploratory laparotomy was performed and

25 cm of his ileum resected

.

Bowel sounds are absent

. He has a right subclavian CV-line.

Considering that his

Ht=180cm , Wt=60kg (6 month ago: 70 kg) and

Age=38 y.o, what is your recommended TPN formula for him?

  

BEE=

66.47+13.75

× 60+5 × 180-6.76

× 38=1535 kcal/d

TEE=

1535 × 1.2

× 1.2 = 2200 kcal/d Intralipid 10%= ? 2200 × 30%= 660 kcal 1ml ≡ 1.1 kcal 660 : 1.1 = 600 ml ( 500ml)  Dext 50%= ? 2200 – 550= 1650 kcal 1g dextrose ≡ 3.4 kcal 1650 : 3.4= 485 g Dext  50g ≡ 100 ml 485 g ≡ 970ml (1000ml) Aminofusion 10 %= ? 1.5 g/kg/d × 60 kg= 90g/day 10g ≡ 100 ml 90g ≡900 ml (1000ml)

Electrolytes (daily requirements for TPN):

 Na: 80-100 mEq (50 - 100 ml NaCl 5%)  K: 60-80 mEq (30 ml KCl)  Cl: 50-100 mEq  Mg: 8-16 mEq (5 -10 ml MgSo4 20%)  Ca: 5-10 mEq (10-20 ml Ca Gluconate 10%)  P04: 15-30 mEq  Acetate: 50-100 mEq



Vitamins:

A, D, E, Water soluble vitamins 

Trace Elements:

 Zn, Se, Cu, Cr, Mn 

↓ Zn

 Delayed ulcer healing, Dermatitis, Alopcia (5α reductase), Diarrhea  ↓ Se: Low activity of SOD & Deiodinase 

Amp B Complex + Amp Vit C MV Therapeutic ( Zn, Cu, Mn)

Special Considerations

 Max infusion rate of dextrose: 0.5g/kg/h (to avoid hyperglycemia, glycosuria, fatty liver, hyperosmolar coma)  K should be added to dextrose solutions  Slow starting & slow tapering of Dext 50%  If BS>200, Insulin should be added  some brands of lipids can be mixed with Dext+Aminifusion in the same IV container

Special Considerations



Intralipid contraindications:

 Severe egg allergy  Hyperlipidemia 

Special aminoacid products:



Hepatamine:

for Hepatic Failure  ↑ branched chain aa ( leu, isoleu, val)  Nephramine: for Renal Failure  Primarily essential aa with lower concentrations

Monitoring:

 

Baseline:

Wt, Na, K, BUN, Cr, Glu, Ca, P, Mg, CBC, PT, INR, TG, LFT, Alb, Pre-Alb

Daily:

Wt, V/S, I-O, Na, K, BUN, Cr, Glu, Sign/Symptoms of infection 

2-3 times a week:

CBC, Ca, P, Mg 

Weekly:

Alb, Pre-Alb, LFT, INR, Nitrogen Balance

Adding other drugs to TPN

   INS Heparin H2-blocker   Alb Aminophylline 

Vit K & Bicarbonate should not be added

Complications

     Endocrine & metabolic  Fluid overload, hypercapnia, hyperglycemia, hyper /hypokalemia, hyper-/hypophosphatemia, refeeding syndrome Hepatic  Cholestasis, cirrhosis (<1%), gallstones, liver function tests increased, pancreatitis, steatosis, triglycerides increased Renal  Azotemia, BUN increased Infectious  Bacteremia, catheter-induced infection, exit-site infections Other: Pneumothorax, Thrombophlebitis

Refeeding syndrome

 In patients with long-standing or severe malnutrition  Is a medical emergency, consist of:  Electrolyte disturbances (eg, potassium, phosphorus)  Respiratory distress  Cardiac arrhythmias, resulting in cardiopulmonary arrest  Do not overfeed patients; caloric replacement should match as closely as possible to intake

Conclusion

    Malnutrition is a common problem & Nutritional support is indicated in many hospitalized patients Enteral nutrition is better, but some patients with GI problems need TPN Dextrose & Intralipid should be used as calorie sources and Aminofusion as aminoacid source Special monitoring should be considered for patients especially I-O, Na, K and Glu