TPN

1. Nutrition for Critically ill Patients
(TPN)
1Prof. Dr. RS Mehta, BPKIHS

2. Nutrition
• Nutrition allows the body to be
provided with all basic nutrients
substrates and energy required for
maintaining or restoring all vital body
functions from carbohydrate and fat
and for building up body mass from
amino acid.
2Prof. Dr. RS Mehta, BPKIHS

3. Clinical Manifestations: Malnutrition
• Weight loss
• Reduced basal metabolism
• Depletion skeletal muscle and adipose
(fat) stores
• Decrease tissue turgor
• Bradycardia
• Hypothermia
3Prof. Dr. RS Mehta, BPKIHS

4. 4Prof. Dr. RS Mehta, BPKIHS

5. 5Prof. Dr. RS Mehta, BPKIHS

6. Total Parentral Nutrition
6Prof. Dr. RS Mehta, BPKIHS

7. Total Parenteral Nutrition Indication
• When normal oral feeding is not possible.
e.g.: Chron’s disease, gastric & esophageal carcinoma,
paralytic ileus, generalized peronitis, GI. obstruction, intractable
vomiting.
• When food is incompletely absorbed.
e.g.: Major burns, multiple injuries, radiation therapy,
ulcerative colitis, chemotherapy treatment, short bowel
syndrome.
• When food intake is undesirable, in case it is
prudent to rest the bowel.
e.g.: Post GIT surgery, chronic inflammatory diseases,
intractable diarrhea.
7Prof. Dr. RS Mehta, BPKIHS

8. Total Parenteral Nutrition Indication
• In patients who are able to ingest food, but
refuse to do so.
e.g.: Geriatric post-operative patients, adolescents
with anorexia nervosa, some psychiatric patients
with prolonged depression.
• In patients who, as a consequence of their
illness are going to be, or have been NPO for
5 – 7 days.
8Prof. Dr. RS Mehta, BPKIHS

9. Indications for TPN
Short-term use
• Bowel injury, surgery, major trauma or burns
• Bowel disease (e.g. obstructions, fistulas)
• Severe malnutrition
• Nutritional preparation prior to surgery.
• Malabsorption - bowel cancer
• Severe pancreatitis
• Malnourished patients who have high risk of
aspiration
Long-term use (HOME PN)
• Prolonged Intestinal Failure
• Crohn’s Disease
• Bowel resection
9Prof. Dr. RS Mehta, BPKIHS

10. Parenteral Nutrition
Central Nutrition
• Subclavian line
• Long period
• Hyperosmolar solution
• Full requirement
• Minimum volume
• Expensive
• More side effect
Peripheral nutrition
• Peripheral line
• Short period < 14days
• Low osmolality
< 900 mOsm/L
• Min. requirement
• Large volume
• Thrombophlebitis
10Prof. Dr. RS Mehta, BPKIHS

11. Routes of TPN
Central TPN
(usual osmolarity = 2000 mosmol/L)
Advantages:
 Can provide full nutritional support (No limits in
concentration of dextrose and amino acids)
 No risk of thrombophlebitis, No pain.
Disadvantages:
 Requires surgery
 More risk of sepsis than peripheral TPN
 High risk of mechanical complications
11Prof. Dr. RS Mehta, BPKIHS

12. Routes of TPN
Peripheral TPN
maximum osmolarity;
neonates = 1100/L, Pediatrics = 1000/L, Adults = 900/L
Advantages:
 Does not require surgery
 Less risk of sepsis than central TPN
 No risk of mechanical complications
Disadvantages:
 High risk of thrombophlebitis
 Painful
 Does not provide full nutrition support.
 Needs more fluids to provide more nutrition. (maximum dextrose =
7.5% and AA = 2.5%).
12Prof. Dr. RS Mehta, BPKIHS

13. Note
PPN can infuse through central line but
central TPN can NOT infuse through
the peripheral line
13Prof. Dr. RS Mehta, BPKIHS

14. Prof. Dr. RS Mehta, BPKIHS
Calculating the Osmolarity of a
Parenteral Nutrition Solution
Multiply the grams of dextrose per liter by 5.
Example: 100 g of dextrose x 5 = 500 mOsm/L
Multiply the grams of protein per liter by 10.
Example: 30 g of protein x 10 = 300 mOsm/L
Multiply the (mEq per L sodium + potassium +
calcium + magnesium) X 2
Example: 80 X 2 = 160
Total osmolarity = 500 + 300 + 160 = 960 mOsm/L
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15. Parenteral Nutrition
• Peripheral Parenteral
Nutrition (15 lit D5W/day for a
70 kg !!!)
• Central Parenteral Nutrition
(TPN)
– Needs CV-line to administer
hyperosmolar solutions
15Prof. Dr. RS Mehta, BPKIHS

16. 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
16Prof. Dr. RS Mehta, BPKIHS

17. 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
17Prof. Dr. RS Mehta, BPKIHS

18. Fluid: mL/day
• 30-40 mL/kg
19Prof. Dr. RS Mehta, BPKIHS

19. 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
20Prof. Dr. RS Mehta, BPKIHS

20. 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
21Prof. Dr. RS Mehta, BPKIHS

21. Protein need in Hepatic failure
• Acute management when other treatments
have failed:
– 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
22Prof. Dr. RS Mehta, BPKIHS

22. 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
23Prof. Dr. RS Mehta, BPKIHS

23. Components of TPN Formulations
Macro:
Calorie: Dextrose 20%, 50%
Intralipid 10%, 20%
Protein: Aminofusion 5%, 10%
Micro:
Electrolytes (Na, K, Mg, Ca, PO4)
Trace elements (Zn, Cu, Cr, Mn, Se)
24Prof. Dr. RS Mehta, BPKIHS

24. Dextrose
• 20%, 50% ( from CV-line)
• 3.4 kcal/g
• 60-70% of calorie requirements should
be provided with dextrose
25Prof. Dr. RS Mehta, BPKIHS

25. Dextrose: Contraindications
• Hypersensitivity to corn or corn products
• Hypertonic solutions in patients with
intracranial or intra-spinal hemorrhage
26Prof. Dr. RS Mehta, BPKIHS

26. Abrupt withdrawal
• Infuse 10% dextrose at same rate and monitor
blood glucose for hypoglycemia
27Prof. Dr. RS Mehta, BPKIHS

27. Monitoring
28Prof. Dr. RS Mehta, BPKIHS

28. Prof. Dr. RS Mehta, BPKIHS
Monitoring
• Avoid overfeeding
• Avoid respiratory problem
• Promote nitrogen retention
• Triglyceride clearance
• Fluid and electrolyte
• Weight
• Liver function
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29. Complications of TPN
30Prof. Dr. RS Mehta, BPKIHS

30. Prof. Dr. RS Mehta, BPKIHS
Complication
• Mechanical: occlusion, catheter removal,
improper rate, thromboses, pneumothorax.
• Infection: catheter related
• Metabolic: re-feeding syndrome, hyperglycemia,
fluid & electrolyte disturbance
• Organic system: hepatobiliary complication,
respiratory, cardiovascular, renal
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31. 32Prof. Dr. RS Mehta, BPKIHS

32. Prof. Dr. RS Mehta, BPKIHS
Transitional Feeding
• Maintain full PN support until pt is tolerating 1/3 of needs
via enteral route
• Decrease TPN by 50% and continue to taper as the enteral
feeding is advanced to total
• TPN can reduce appetite if >25% of calorie needs are met
via PN
• TPN can be tapered when pt is consuming greater than 500
calories/d and d-c’d when meeting 60% of goal
• TPN can be rapidly decreased if pt is receiving enteral
feeding in amount great enough to maintain blood glucose
levels
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33. TPN
• Doctors decide patient needs it
• Dietitian sees patient
• Decides best regime
• Orders bag from pharmacy
• Made up aseptically to requirements
• Start low and build up
• Monitor bloods
34Prof. Dr. RS Mehta, BPKIHS

34. Access for PN
• Usually central line in ICU – keep a clean port
if PN may be needed. 5 lumen
• Short term PN – can have PIC (need a different
formula) or PICC
• Long-term TPN – tunnelled subclavian
catheter (Hickman) or subcutaneous port is
usually inserted – OBSERVE STRICT ASEPSIS if
handling these lines.
35Prof. Dr. RS Mehta, BPKIHS

35. 36Prof. Dr. RS Mehta, BPKIHS

36. Overfeeding
• Lactic acidosis
• Hyperglycaemia
• Increased infections
• Liver impairment (Alk phos, ALT, GGT,
acalculous cholecystitis)
• Persistent pyrexia
37Prof. Dr. RS Mehta, BPKIHS

37. Complex nutrition: Monitoring
• Urea, Electrolytes, phosphate, calcium,
magnesium
• Glucose
• LFTs
• Fluid balance
• Haematology
• Weight
• Trace elements if long-term
38Prof. Dr. RS Mehta, BPKIHS

38. Conclusion
• Do not forget about feeding
• Keep an eye on whether nutritional
targets are being met
• Speak to the surgeons and dietician
• Do not be reluctant to start PN in a
supplemental capacity
• Avoid hyperglycaemia
• Nutrition is often neglected
39Prof. Dr. RS Mehta, BPKIHS

39. Thank you
Prof. Dr. RS Mehta, BPKIHS 40

40. 41Prof. Dr. RS Mehta, BPKIHS