Intravenous Nutrient Solutions

8/3/2019 Intravenous Nutrient Solutions

1/28

INTRAVENOUS

NUTRIENT SOLUTIONS

Sayed nour


2/28

Parenteral nutrition is the continuousinfusion of a hyperosmolar solution

containing carbohydrates, proteins, fat,and other necessary nutrients through anintravenous route

Parenteral nutrition is used when theenteral route is unable to provide orsustain sufficient caloric intake.


3/28

Goals of Nutrition Support

To minimize protein breakdown,

To preserve lean body mass, To promote protein synthesis,

and

To optimize immune responses


4/28

PN Summary Guidelines

1. Determine if PN is truly indicated

2. Assess the patient (medical history,

medication profile, anthropometricdata & lab values)

3. Determine need for long-term vs.short term


5/28

4. Confirm or establish adequate IV access

Peripheral or central?

5. Determine estimated kcal, protein andlipid needs

2030 kcal/kg

Protein 0.81.5 gm/kg Higher levels may be needed in severe

catabolic states

Lipid to provide 30% ofkcals


6/28

6. Determine initial electrolyte,vitamin and trace element

requirements; consider ongoinglosses

7. Consider any additional additives to

PN formulation including insulinand H2-receptor antagonists


7/28

8. Monitor for: Risk of refeeding syndrome

Glucose intolerance

Start low & advance slowly if labs stableover 24-48 hours

Fluid, electrolyte, metabolic, macro- andmicro-nutrient changes

Complications sepsis, thrombosis, abuse9. Initiate trophic feedings or convert

patient to PO or enteral feeding whenfeasible


8/28

Dextrose Solutions

the standard nutritional support regimen usescarbohydrates to supply approximately 70%of the daily (nonprotein) calorierequirements.

These are provided by dextrose (glucose)solutions, which are available in variousstrengths.

As dextrose is not a potent metabolic fuel,the solutions must be concentrated toprovide enough calories to satisfy dailyrequirements.

As a result, the dextrose solutions used forTPN are hyperosmolar and should be infusedthrough large central veins


9/28

Intravenous Dextrose Solutions


10/28

Amino acid solutions

Amino acid solutions are mixed together withthe dextrose solutions to provide the dailyprotein requirements.

A variety of amino acid solutions are availablefor specific clinical settings.

The standard amino acid solutions containapproximately 50% essential amino acids and50% nonessential + semiessential amino acids


11/28

Amino acid cont

The nitrogen in essential amino acids ispartially recycled for the production ofnonessential amino acids

So metabolism of essential amino acidsproduces less of a rise in the blood ureanitrogen concentration than metabolism ofnonessential amino acids

amino acid solutions designed for use in renalfailure are rich in essential amino acids


12/28

Standard and Specialty Amino

Acid Solutions


13/28

Glutamine

Glutamine is the principle metabolic fuel forintestinal epithelial cells,

Glutamine-supplemented TPN has an

important role in maintaining the functionalintegrity of the bowel mucosa and preventingbacterial translocation.

Glutamine is formed when glutamic acid

combines with ammonia in the presence ofthe enzyme glutamine synthetase. Glutamic acid is given as exogenous source of

glutamine.


14/28

Amino Acid Solutions with

Glutamic Acid


15/28

Lipid Emulsions

Intravenous lipid emulsions consist ofsubmicron droplets (=0.45 mm) of cholesteroland phospholipids surrounding a core of long-chain triglycerides

The triglycerides are derived from vegetableoils (safflower or soybean oils) and are rich inlinoleic acid, an essential polyunsaturatedfatty acid

lipid emulsions are available in 10% and 20%strengths (the percentage refers to grams oftriglyceride per 100 mL of solution).

The 10% emulsionsprovide approximately 1kcal/mL, and the 20% emulsions provide 2kcal/mL


16/28

Unlike the hypertonic dextrose solutions, lipidemulsions are roughly isotonic to plasma

Can be infused through peripheral veins. Thelipid emulsions are available in unit volumesof 50 to 500 mL

They can be infused separately (at amaximum rate of 50 mL/hour) or added to thedextroseamino acid mixtures.

The triglycerides introduced into thebloodstream are not cleared for 8 to 10 hours,and lipid infusions often produce a transient,lipemic-appearing (whitish) plasma.


17/28

Intravenous Lipid Emulsions


18/28

Lipid Restriction

Lipids are used to provide up to 30% of thedaily (nonprotein) calorie requirements.

Dietary lipids are oxidation-prone and can

promote oxidant-induced cell injury Use of lipids in critically ill patients (who often

have high oxidation rates) should berestricted.

Minimal amounts (4% of calorie) of lipidinfusion is necessary to prevent essentialfatty acid deficiency (cardiomyopathy,skeletal muscle myopathy)


19/28

Additives

Electrolytes

Most electrolyte mixtures contain sodium,chloride, potassium, and magnesium; they also

may contain calcium and phosphorous.

The daily requirement for specific electrolyte canbe specified in the TPN orders.

If no electrolyte requirements are specified, theelectrolytes are added to replace normal dailyelectrolyte losses.


20/28

Normal Serum ElectrolytesParenteral & Enteral Intake Ranges


21/28

Vitamins

Aqueous multivitamin preparations are added to thedextroseamino acid mixtures.

One unit vial of a standard multivitamin preparation willprovide the normal daily requirements for most vitamins

Enhanced vitamin requirements in hypermetabolic patientsin the ICU may not be satisfied.

Some vitamins are degraded before they are delivered.Some examples are riboflavin and pyridoxine (which aredegraded by light) and thiamine (which is degraded bysulfites used as preservatives for amino acid solutions)


22/28

Vitamins

Vitamin RDI (FDA/AMA/NAG) Thiamine (B1) 6 mg Riboflavin (B2) 3.6 mg Pyridoxine (B6) 6 mg

Cyanocobalamin (B12) 5 mcg Niacin 40 mg Folic acid 600 mcg Pantothenic acid 15 mg Biotin 60 mcg

Ascorbic acid (C) 200 mg Vitamin A 3300 IU Vitamin D 5 mg Vitamin E 10 IU Vitamin K 150 mcg


23/28

Trace Elements

A variety of trace element additives are available

Most trace element mixtures contain chromium,copper, manganese, and zinc, but they do notcontain iron and iodine.

Some mixtures contain selenium, which has a role

in proctection against oxidation injury Routine administration of iron is not

recommended in critically ill patients because ofthe pro-oxidant actions of iron


24/28

Trace Element Preparations

and Daily Requirements


25/28

Monitoring PN Patients

Clinical Status Vital signs

Intake/output

Urine, Stool, Other (eg fistula output) Weight

Fluid requirements

Patient complaints Physical exam

Overall clinical status


26/28

Monitoring PN Patients

Metabolic and Biochemical Aspe

Blood studies Renal function: Lytes, Mg, Ca, Phos, BUN, Cr

Hematologic: CBC (Hgb, WBC, Plt), INR

Liver function: Alk Phos, AST/ALT, Bilirubin

Glucose/lipid tolerance: Glucose, Triglycerides

Iron status: Iron, TIBC, Ferritin

Serum proteins: Albumin

Insulin coverage

DEXA


27/28

thank you


28/28

Thank you

Documents

Intravenous Nutrient Solutions