Transcript Parenteral Nutrition Designing the Solution

Parenteral Nutrition
Designing the Solution
Mark H. DeLegge, MD, FACG, AGAF,
FASGE
Digestive Disease Center
Medical University of South Carolina
Avoid That Which is Unknown
Lipids
Protein
Carbohydrates
Parenteral Nutrition
 Infusion of nutrients through a vein
 Indications: dysfuntional GI system
– Malabsorption
– Obstruction
– Fistula
– Inability to obtain enteral access
– Bowel rest ?
Parenteral Nutrition
 Central: Infused into a major vein (CPN)
– Generally with catheter tip in the last 1/3 of
Superior Vena Cava
 Peripheral: Infused into a peripheral vein
(PPN)
– Limited by mixture osmolality (< 900 mOsmo)
– May limit ability to deliver total caloric needs
PPN
CPN
Superior Vena
Cava
Osmolality Gradient and
Carbohydrates
Glucose
Concentration %
Calories
Kcal/L
Osmolality
mOsmo/L
5
170
252
10
340
505
20
680
1010
40
1360
2020
50
1700
2525
60
2040
3030
70
2380
3535
Knowing the Solution
 % Solution
 10% AA = 10 gm AA/100 H20
 20% Lipids = 20 gm lipids/100 cc H2O
 30% Jack Daniels = 30 gm Jack
Daniels/100 cc H20
What You Need to Know To Write
A PN Prescription
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Calorie Requirements
Protein Requirements
Electrolyte Requirements
Mineral Requirements
Vitamin Requirements
Water Requirements
Other Additives
Calorie Needs
 Harris Benedict:
 Male 66 + 13.8 (wt in
kg) + 5 (height in cm) –
6.8 (age in years)
 Female 655 + 9.6
(weight in kg) + 1.8 (ht
in cm) – 4.7 (age in
years)
Stress Factor
Mild 1-1.2
Moderate 1.3-1.4
Severe 1.5
Simple Calorie Calculation
 Maintenance/mild
stress: 20-25
kcal/kg/day
 Moderate stress: 2528 kcal/kg/day
 Severe Stress : 28-35
kcal/kg/day
Protein Needs
 Maintenance – mild
stress: 0.8-1.2
g/kg/day
 Moderate stress: 1.31.5 gm/kg/day
 Severe stress: 1.5 –
2.0 gm/kg/day
 Very high stress: > 2
gm/kg/day
Make Note of Common Lab Values
Na+
K+ Serum
Chloride
CO2
BUN
Creatinine
Calcium
Phosphorus
Magnesium
135-145 mEq/L
3.5-5.0 mEq/L
98-107 mmol/L
22-32 mmol/L
8-20 mg/dL
0.7-1.3 mg/dL
8.4-10.2 mg/dL
2.3-4.7 mg/dL
1.6-2.3 mg/dL
Example of a Standard PN
Electrolyte Matrix
 NACl
 Na Acetate
 K Phosphate
75 mEq/L
25 m Eq/L (CO2)
15 mmol
 (3 mmol of P = 4.4 mEq/K)
 Na Phosphate
15 mmol
 (3 mmol of P = 4 mEq Na)
 Ca Gluconate
 Mg sulfate
2 gm
1 gram
Standard Trace Minerals
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Added to Daily PN Prescription
Chromium
10 mcg
Copper
1 mg
Manganese
0.5 mg
Selenium
60 mcg
Zinc
5 mg
Standard Multivitamins
Provided Daily
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Vitamin A
Vitamin D
Vitamin E
Vitamin B1
Vitamin B2
Vitamin B3
Vitamin B5
Vitamin B6
Vitamin C
Biotin
Folic Acid
Vitamin K
3300 IU
200 IU
10 IU
6 mg
3.6 mg
40 mg
15 mg
6 mg
200 mg
60 mcg
600 mcg
150 mcg
Daily Fluid Needs
 30 cc/kg/day
 Reduce if volume overloaded
 Increase for excessive stool, urine, vomiting,
sweating.
 You do not have to correct major electrolyte,
mineral, fluid abnormalities in the PN
solution. Use a supplemental infusion.
Additives
 H2 Blocker
 Heparin
 Insulin
– Need at least 10 units/L to see clinical effect
– Add ½ to ¾ of previous day’s insulin
requirements to TPN bag
Additional Potential Additives
Vitamin C:
500-1000 mg/day for wound healing.
Zinc:
3-5 mg/day for wound healing
Folic Acid:
1 mg/day with alcohol abuse or pregnancy
Thiamine:
100 mg/day with alcohol abuse
Important Facts
 Lipids: no more than
2.5 gm/kg/day
 Carbohydrates:
Maximal glucose
infusion rate 3-5
g/kg/day
 Protein: as described
 1 gram lipids = 9 kcal
 1 gram protein = 4 kcal
 1 gram carbohydrates
= 3.4 kcal
The Situation
 A 40 year old male s/p recurrent fistula
formation in the distal jejunum. He has lost 6
kg in 2 weeks. A central PN catheter is
placed and you are asked to write a PN
order. The patient weighs 70 kg.
Estimated Needs
 Calories
 Protein
 Fluids
30 kcal/g x 70 kg = 2100 kcal
1.2 g/kg x 70 kg = 84 kg
30 ml/kg = 2100 cc
 His electrolytes are normal except for a K+ of 3.3.
1st Add Protein
 84 g of protein
 4 kcal/g (326 kcal)
 2100 kcal – 326 kcal = 1774 kcal more
required
2nd Add Lipids
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1-1.5 g/kg
70 kg x 1 g/kg = 70 gm
70 gm = 700 kcal
1774 calories – 700 kcal = 1074 kcal
remaining
3rd Add Carbohydrates
 1074 kcal remaining
 1074/3.4 kcal/g carbohydrate = 295 g
 Double check for maximal carbohydrate
infusion
 295 g carbohydrate/70 kg = 4.21 g/kg/day
Determine a Volume
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70 kg x 30 cc/kg = 2100 cc
Add multivitamins
Add trace minerals
Add drugs if necessary
What if the TPN Form Asks Me to
Add Components as Solutions?
 15% amino acids (15 gm/100 cc)
– We need 84 grams = 560 cc
 20 Lipids (20 gm/100 cc)
– We need 70 gm = 350 cc
 70% dextrose (70 gm/100 cc)
– We need 295 gm = 421 cc
– 2100 cc volume – 1361 cc = 739 cc H20
– Add trace minerals, multivitamins and other
drugs
How do you Determine a Rate
 Continuous
 Total volume/24 hr = cc/hr
 2100/24 = 87 cc/hr
 Intermittent
 Total volume over 12 hours
 2100/12 = 175 cc/hr
Conclusion
 1. Be able to determine calorie, protein, fluid
needs
 2. Be familiar with a standard electrolyte
formulation
 3. Make your PN formula sequentially
 4. Be familiar with solutions and what they
mean
 5. Add this to your knowledge base
Don’t leave Nutrition Support up
to Someone Else