The following content will be displaying general guidelines for TPN. The information below to be used for education purposes only and not to substitute your clinical judgment.

General Guidelines for TPN

*General Guidelines for TPN*

Planning nutritional therapy for hospitalized patients.

A) Nutritional screening:

it’s an initial and ongoing process of identifying characteristics known to be associated with nutrition problems in order to identify patients who are nutritionally at risk for malnutrition or are malnourished.

B) Assessment of patients:

medical screening - Our Best TDP General Guidelines for TPN - in 5 Points
  1. Medical history review:

For past and present recent medical problems that have affected or may affect nutritional status. For example, medications, diagnostic procedures, surgeries, chemotherapy, radiation, etc.

2. Medical record review:

To identify factors that may affect nutritional status.

For example:

  • Existing nutrient deficiency (ies).
  • Acute or chronic illness with nutritional consequences.
  • History of nutritional related problems.
  • Medications with potential drug/nutrient interactions.
  • Psychosocial factors, such as, alcoholism, smoking, financial situations.
  • Nutritional assessment:
  • Nutritional history to identify risk of malnutrition.
  • Pattern of weight loss (continuing, stabilizing or reversing).
  • Physical examination to include Anthropometrics (triceps skin fold mid upper arm circumference) to estimate subcutaneous to estimate fat reserve and muscle.
  • Biochemical assessment: which including visceral proteins, (albumin, transferring pr pre-albumin).
  • Immunocompetence secondary to malnutrition, (total lymphocyte count).
  • Calories requirement assessment to establish nutritional needs for each patient:
    • Basal energy expenditure – BEE and total energy expenditure -TEE
    • Metabolic status, which is trauma, sepsis or burns.
    • Route of administration, such as oral, enteral, peripheral or central IV.
Age in yearsRecommended Caloric Intake
0-180-140 kcal/kg/day
1-385-95 kcal/kg/day
4-680-90 kcal/kg/day
7-1070-80 kcal/kg/day
11-1455-65 kcal/kg/day
15-adults25-50 kcal/kg/day
General Guidelines for TPN
  • Protein requirements assessment:
Amino Acids requirements
0-6 months2-3 g/kg/day
6m-6 years2-2.5 g/kg/day
7-12 years1.5-2 g/kg/day
> 12 years-adults0.8-1.5 g/kg/day
General Guidelines for TPN
  1. Recommended Dietary allowance (RDA) for adults is 0.8 gram per kg of ideal body weight (IBW)
  2. Disease related requirements (hepatic dysfunction, renal dysfunction, dialysis and non dialysis requirements etc.
  3. Metabolic stress / trauma requirements range is one to 2.5 grams per kg per day according to severity of condition.
  4. Non protein calories to nitrogen ratio is needed for optimal protein synthesis.
  5. The ratios of a standard nutritional formulas to achieve positive nitrogen balance are typically about 100 to 150 non protein calories per gram of nitrogen. Lower ratios are indicated for stress or trauma, while higher ratios for pediatrics, non-stress patients or for those with impaired protein metabolism.
  6. Nitrogen balance is used to determine the amount of nitrogen required to maintain nitrogen equilibrium
  7. Protein should be only used to build new tissue and not to contribute in daily calorie can intake (glucose and lipid should be used in sufficient quantities to avoid protein catabolism)

C) Prescribing of TPN:

doctor prescribing - Our Best TDP General Guidelines for TPN - in 5 Points

1. Fluid requirements:

Any fluid imbalance should be corrected; fluid intake urine output and IV drugs will be taken into account when circulating or calculating fluid requirements.

The TPN fluid should:

  • Contain the required total calories.
  • Provide sufficient hydration and prevent hyper-osmolarity problems.
  • Replace the insensible losses that occur during surgery, for pyrexial or hyperventilating patients.

Fluid restrictions is for the deciding factor in selecting hypertonic concentrated solutions for infusion through central vein rather than a more diluted solution for peripheral administration.

Maintenance requirements calculated as following:

Neonates: 80-150ml/kg/day according to gestational age, post natal age, incubator condition and phototherapy.

The following table shows the fluid volume in ml/kg/day for the given age of the newborn up to one month, and that volume will be corresponding to the infant weight.

Day 1Day 2Day 3 to 1 month
wt< 1200 gm80-100100-120120-140
1201 – 2500 gm7080-100100-120
2501 – 4500 gm50-6060-80100
with the aim of delivering 150ml/kg/day at day 7

Infants to adults:

Wt. (1-10 kg)100ml/kg/day
10.1 – 20 kg1000ml + 50ml/kg above 10 kg
>20 kg1500ml + 20ml/kg above 20 kg
Additional 10% of maintenance fluid requirements for each degree of fever above 37°C
iv drip - Our Best TDP General Guidelines for TPN - in 5 Points
Amino Acids in TPN

2. Protein as amino acid solutions:

  • 1gm protein yields 4kcal of energy.
  • 1gm nitrogen contains 6.25 gm protein.
  • Aminoplasmal 10%(500ml / bottle) is the available regular amino acid solution.
  • Specialized amino acids formulas will be available if efficacy has been approved:
    • For uremic patients.
    • For patient with liver insufficiency (hepatic encephalopathy).
    • For neonates, infants and young children: Primene 10%.

The increase in concentration should be gradual, till maximum recommended strength:

AgeStart at conc. of Increased by
Neonates0.5% amino acid solution0.5% every other day
Infants1% amino acid solution0.5% every day
Children1% amino acid solution0.5% every day
Adults4.25% amino acid solution
Maximum recommended allowable conc. of amino acid solution for infants and children is 2% when given peripherally and 3% when given centrally.

Osmolarity of TPN solution: The maximum osmolarity must not exceed the following values when administered peripherally:

Age groupPeripheral line TPN
Neonates and infants 1100 mOsmol/L
Pediatric < 11 years1050 mOsmol/L
Adolescent – Adult900 mOsmol/L
The osmolarity of central line TPN solution may reach 2000 mOsmol/L for a fluid restricted patient.

3. Dextrose:

IBWMaximum utilization of glucoseMaximum rate of oxidation
< 8 kg25 gm/kg/day17 mg/kg/min
8 – 15 kg20 gm/kg/day17 – 14 mg/kg/min
15.1 – 25 kg16 gm/kg/day14 – 11 mg/kg/min
25.1 – 50 kg10 gm/kg/day11 – 7 mg/kg/min
> 50 kg and adults8 gm/kg/day5 mg/kg/min
General Guidelines for TPN

Begin TPN dextrose infusion at the same dextrose load provided by the current IV fluids, advance 1-3 mg/kg/min as tolerated, till maximum oxidation rate.

The rate of dextrose infusion should be limited to its maximum rate of oxidation, to avoid excess glucose that will be diverted to non oxidative pathway (glycogen storage, hepatic lipogenesis, cholestasis, hepatomegaly, etc.).

  • 1 gm Dextrose provides 3.4 kcal of energy.
  • It is supplied as 25%, 50%, or 70%.
  • Maximum allowable concentrations are 12.5% when given by peripheral vein, and 20-25% when given by central vein, concentrations higher than 25% may be indicated for fluid restricted patients.
  • Infusion and oxidation of high amount of glucose will require a compensatory increase of minute ventilation due to increased CO2 production.
  • The increase in concentration should be gradual, till maximum recommended strength to allow appropriate response of endogenous insulin and to avoid osmotic diuresis:
Age
Premature and newborn infants5% initiallyIncreased by 2.5% every 2 daysMaximum 10% if peripheral line and to 20% if central line
Older infants and children5% initiallyIncreased by 2.5% every dayMaximum 10% if peripheral line and to 20% if central line
Older children and adults5% initiallyIncreased by 5% every dayMaximum 12.5% if peripheral line and to 25% if central line
General Guidelines for TPN

Urine sugar spills:
For +1 and +2 no insulin is required.
For +3 obtain stat blood glucose; if exceeds 250 mg%.
Commence blood glucose every 4 hours and potassium measurements and proceed as follow:

Blood glucoseInsulin IV
250 to 300 mg %5 U regular insulin
301 to 350 mg %10 U regular insulin
351 to 400 mg %15 U regular insulin
Blood glucose 400 mg % draw stat serum osmolarity.

Further management will be determined on basis of response to above.

  • insulin should be used cautiously to avoid hypoglycemia and because it promotes the deposition of fatty acids in body fat stores, making them less available for important biochemical pathways.
  • Until a patient is stabilized on a consistent dosage of insulin, it is more cost effective to provide insulin separately to avoid wasting of TPN formulations that might be discarded if the insulin dosage needs to be changed.
  • 1/2 to 2/3 the previous day’s sliding scale requirements may be added to daily TPN formula.
  • Recommended maximum insulin per liter is 50 U although up to 100 U/Liter has been added with satisfactory results.

4. Lipids:

  • Lipofundin 20% is available. It contains a mixture of medium and long chain triglycerides (MCT/LCT) in 1:1 ratio.
  • 20% emulsion provides 2kcal/ml.
  • Fat is concentrated source of calories in an isotonic medium that is useful for peripheral administration.
  • It is a source of essential fatty acids (EFA )required the for prevention or treatment of essential fatty acid deficiency that may develop during extensive parenteral nutrition with dextrose.
  • It substitutes carbohydrates when dextrose must be limited due to glucose intolerance or excessive respiratory load.
  • Infuse lipid over 20 hours to allow plasma lipid free for 4 hours before morning blood sampling as lipid me interfere with lab results as well as inaccurate plasma TG levels.
  • Lipid syringes and tubing should be protected from light by wrapping it in foil.
  • Daily requirements:
    Lipids should not provide more than 60% of the non-protein calories (maximum 3 gm/kg)
AgeInitiallyIncreased byMaximum daily dose
Premature infants 0.5 gm/kg/day0.5-1 gm/kg/day3 gm/kg/day
Infants1 gm/kg/day0.5-1 gm/kg/day3 gm/kg/day
Older children and adults1 gm/kg/day0.5-1 gm/kg/day2 gm/kg/day
General Guidelines for TPN
  • Infusion rate of lipids:
    In pediatric: 0.1 ml/min for the first 10-15 minutes (if no allergic reaction, respiratory distress, or fever occurs, you may continue at a regular rate for the day s dose).
    In adults: on the first day of fat emulsion only, run test infusion at 60 ml/hour for 30 minutes and observe the patient for cardiovascular instability, dyspnea, chest pain, CNS, and GI symptoms. If there are no untoward effects, proceed with the remainder of fat emulsion at 80 ml/hour.
  • The maximum rate of infusion not to exceed 1.5 ml/kg/hour (120 ml/h for the average adult).
  • Infusion of lipid can be via peripheral catheter, which must be new and sterile and will be used for fat emulsion only. DO NOT use existing IV lines and DO NOT use the line for any other procedures or infusions.
  • Lipid can be given by the same line of dextrose-amino acid solution via a Y-connector proximal to the filter. Y-connector is to be changed daily.
  • Don’t interrupt dextrose-amino acid solution to infuse fat emulsion.
  • FILTER SHOULD NOT BE USED WITH LIPIDS INFUSION.
  • Laboratory slips for T.bilirubin, sodium, potassium, and calcium must be marked (ultracentrifuge) to ensure accurate laboratory values.
  • All patients should have triglycerides, cholesterol, and free fatty acids levels determined once weekly. If TG level > or equal to 400 mg % or if FFA/albumin molar ratio is 4:1, the dose must be adjusted.
  • In neonates: in presence of jaundice requiring phototherapy, lipid > 2 gm/kg/day should be avoided.

5. Electrolytes:

  • Intracellular electrolytes principally potassium, magnesium, and phosphate should be provided for optimum utilization of amino acids.
  • Extracellular electrolytes (sodium, calcium, and chloride in sufficient quantities) should be given.
  • TPN shouldn’t be used to correct major electrolyte abnormalities, in this regard; electrolytes will be added thru separate IV line and not directly added to TPN bag that is currently infused.
  • Phosphate should be added in the first few TPN bags to all patients except if contraindicated.
ElectrolytesDosage formsConcentrationAdult requirementsPediatric
PotassiumPotassium chloride 15%
Potassium phosphate
Potassium acetate
2 meq/ml
4.4 meq/ml
2 meq/ml
70-180 meq/day2-3 meq/kg/d
MagnesiumMagnesium sulfate 50%4 meq/ml8-32 meq/day0.25-0.5 meq/kg/d
PhosphateSodium phosphate
Potassium phosphate
3 mmol/ml
3 mmol/ml
9-30 mmol/day0.5-2 mmol/kg/d
SodiumSodium chloride concentrate
Sodium acetate
4 meq/ml
2.5 meq/ml
2 meq/ml
60-150 meq/day2-4 meq/kg/d
CalciumCalcium gluconate 10%4.5 meq/10ml5-40 meq/day0.5-3 meq/kg/d
ChlorideSodium chloride 23.4%
Or Sodium chloride 14.6%
4 meq/ml
2.5 meq/ml
60-150 meq/day2-4 meq/kg/d
AcetateSodium acetate
Potassium acetate
Variable amounts of acetate and chloride contained in each amino acid solutions.

6. Vitamins:

  • Cernevit is available as intravenous multivitamin combination of both water and fat-soluble vitamins presented in one vial
VitaminEach 5 ml cernevit contains:
Vitamin A3500 IU
Thiamine5.80 mg
Riboflavin5.67 mg
Pyriodoxine5.50 mg
Vitamin B126 mcg
Biotin69 mcg
Folic acid414 mcg
Niacinamide46 mg
Dexapanthenol16.15 mg
Vitamin C125 mg
Vitamin E10.2 mg
Vitamin K1_
Vitamin D220 IU
General Guidelines for TPN
  • The usual daily dosage of adults is 10 ml.
  • Pediatric daily dosage:
Wt. (kg)Dosage (ml)
< 1 kg1.5 ml
1-3 kg3 ml
> 3 kg and up to 11 years of age5 ml
General Guidelines for TPN
  • Intramuscularly administered vitamins:
    1. Vitamin K1 (phytonadione):
Infants0.25-0.5 mgTwice weekly
Older children2 mg if < 2 years
5 mg if 2-5 years
10 mg if > 5 years
Once weekly
Adults10 mg IMWeekly to all adult patients, unless the patient is on daily vitamin K
General Guidelines for TPN

2. Vitamin B12 (cyanocobolamine):

Infants: 50 mcg twice monthly.

Older children: 100 mcg initially and then monthly.

Adults: May be given additionally once a month (1000 mcg) or weekly as required.

*Folic acid is present in Cernivit.

7. Trace elements:

Trace elementInfants and toddlers
mcg/kg/day
Children
mcg/kg/day
Adults
Copper202030 mcg/day
ZincPremature: 300
< 3 months old: 150
> 3 months old: 100
504 mg/day
Manganese1150 mcg/day
Chromium0.20.210-15 mcg/day
(20 mcg/day if intestinal loss)
Selenium2230 mcg/day
Molybdenum0.250.255 mcg/day
Iodide111 mcg/day
General Guidelines for TPN
  • Tracutil, a formulation of 9 trace elements including iron is available for use in TPN for adults.
  • Pediatric trace elements shall be used for neonatal and pediatric patient.
  • Additional supply of zinc and selenium may be needed especially in acute catabolic states, in patients undergoing medium to long-term parenteral nutrition and when there is increased intestinal losses of zinc.
  • Caution in case of impaired renal or liver functions.

Heparin:
0.5-1 unit/ml of the TPN solution added, this amount over 24 hours has little or no effect on a PTT.

Albumin:
Maximum in TPN = 60 gm/day or 20 gm/L.

D) Monitoring the patient:

Frequency of routine monitoring should be increased in critically ill patients.

Routine monitoring parametersFrequency
Urinary glucose, ketones and specific gravityEvery voided specimen until stable, then daily
Finger stick glucoseEvery 6 hours until stable
Temperature, Vital signsEvery 4 hours
Weight, intake and outputDaily
Serum glucose, Na, K, CL, HCO3, osmolarity, creatinine, and BUNDaily until stable, then twice weekly
Magnesium, Calcium, and PhosphorousDaily until stable, then once weekly
CBC, and prothrombin time, INRBaseline then weekly
Serum protein, albumin, prealbuminBaseline then weekly
LFTsBaseline then twice weekly
Serum cholesterol and triglyceridesEvery day for 2 days then weekly
Blood ammoniaBaseline then weekly in renal and hepatic pt.
General Guidelines for TPN

TPN complications:

  • Most of complications can be avoided by proper precautions and close monitoring of the patient.
  • NST team leader should be notified immediately.
  • IV insertion site shall be checked by the nurse every shift for infection, infiltration, extravasation and phlebitis.
  • Dressing and TPN administration (rate, time of solution change) shall be checked by the nurse every shift.

Suspicion of sepsis:

  • In the event of sudden pyrexia or suspicion of sepsis, the nurse should stop the TPN and inform the attending physician immediately.
  • A full septic screen should be initiated:
    1. Catheters tips when removed should always be sent for culture and sensitivity.
    2. A specimen of TPN collected for culture and sensitivity.
    3. Blood serum sample for culture, sensitivity and electrolytes.
    4. Lumbar puncture (CSF for culture, sensitivity, cell count, lytes and glucose).
    5. Chest X-ray.
    6. Urine for culture and sensitivity.
    7. Endotracheal aspirate (if intubated) for culture and sensitivity.
    8. Peripheral swabs if indicated.

Metabolic complications:
Awareness of the patient problems and the predisposing factors will facilitate their prevention

ProblemPredisposing factorsManagement
Hyperglycemia1-Sepsis
2-Deficit of potassium or phosphorous
3-Insufficient insulin
4-Medications e.g. corticosteroids
1-Sepsis workup and treatment
2-Increase potassium or phosphorous provision
3-Titrate insulin
4-Reduce rate of glucose infusion
Hypoglycemia1-Abrupt withdrawal or interruption of TPN infusion
2-Anabolism
3-Excess insulin
1-Begin dextrose 50% infusion
-Ensure correct tapering of TPN infusion
-If accidental disconnection; start dextrose 10% infusion at the same rate of TPN infusion
2-Monitor blood glucose and potassium
3-Decrease insulin
*All IV insulin drips should be discontinued when TPN is stopped. Uncontrolled hyperglycemia will produce osmotic diuresis, dehydration and coma if sever.
ProblemPredisposing factorsManagement
HypokalemiaLarge glucose infusion
Excessive GI losses (drains, fistula, diarrhea, ..)
Excessive urinary losses (diuretics, amphotericin, ..)
Potassium deficit
Potassium supplements
HypophosphatemiaPhosphate binding antacids
Anabolism
Diabetic ketoacidosis
Phosphate free dialysis
Discontinue phosphate binder
Increase phosphate intake
Feeding gradually
HypomagnesemiaInsufficient intake
Chronic diarrhea
Extensive small bowel resection
Increase magnesium intake
HypocalcaemiaInsufficient intake
Malabsorption
Diuretics
Insufficient vitamin D intake
Hypothyroidism
Mg deficiency
Calcium replacement
Magnesium replacement
HyponatremiaRelative excess of water
Insufficient intake
Pyrexia
Sweating
GI losses
Increase sodium provision
Metabolic acidosisHigh output GI fistula
Excess amino acids
Excess chloride
Renal failure
Decrease chloride or increase acetate provision
Decrease amino acids in TPN
AzotemiaDehydration
Impaired renal function
Excess nitrogen infusion
Correct dehydration
Increase E:N ratio
Elevated LFTsExcess dextrose
Extended enteral feeding
Stress
Infection
EFA deficiency
Excessive nutrients
Provide lipid, decrease Dextrose, or use cycling TPN
HypertriglyceridemiaImpaired clearanceHold IV lipid if ser.TG> 400 mg% (4.5 mmol/L)
Osmotic diuresisFailure to recognize initial hyperglycemia and increased glucose in urineReduce infusion rate
Insulin to correct hyperglycemia
EFA difficiencyInsufficient provision of fatProvide lipid
Excess CO2 production (PCO2)Excess dextrose intakeDecrease dextrose and increase fat intake if possible, increase ventilation
General Guidelines for TPN

Complications related to catheter insertion:
Pneumothorax, puncture of subclavian or carotid artery and air embolism.

Septicemia related to the catheter:
(Vancomycin is the drug of choice), fever should be investigated on occurrence and TPN lines should be changed if no other cause is found, catheter tips must be cultured if the patient becomes septic;

  • If the culture result is positive; the replacement catheter will be removed and a new one will be inserted in different site.
  • If the culture result is negative; the replacement catheter will not be removed.

E) Termination of TPN:

  • Ensure TPN infusion is never stopped abruptly unless absolutely necessary.
  • Check blood sugar levels after TPN is being discontinued until stability assured; blood glucose should be checked every 15-60 min after TPN discontinue.
  • In the event of disconnection, TPN may be stored in the fridge. However aseptic technique must be utilized and the integrity of the TPN maintained to prevent sepsis and unstable blood sugar. If aseptic integrity is compromised a new preparation of TPN will be required.
  • Enteral nutrition (EN) may be used in the transitional phase between parenteral nutrition (PN) and normal oral intake; gradual reduction of PN over a few days, while EN gradually instituted and increased over the same period of time in a way that total intake remains constant.

Temporary discontinuation of TPN for surgery or investigation:

  • Taper TPN by reducing the infusion rate as ordered by the attending physician (20 ml every 15 min until the flow rate is zero).
  • Heparin lock the catheter line when TPN administration is discontinued for more than 2 hours using a dilution of 500 u of heparin in 500 ml of normal saline (Heparin should be infused at a rate less than 2 ml/hour).

Accidental disconnection of TPN:

  • Commence 10% dextrose infusion immediately for 4-6 hours including while lines are changed., run at the same rate as the TPN was infusing via a different port of access to avoid complications of sepsis of TPN line.
  • The TPN catheter tip, blood sample and a sample of the TPN should be sent to microbiology for culture and sensitivity testing whenever the line is removed even in the event of the patient’s death.

Cycling TPN:

It is a maneuver to further reduce the pathophysiologic consequences of TPN administration. It needs to be achieved gradually and the usual goal is to infuse the necessary volume of TPN and lipid over a 16-18 hours period. One hour at each end of the infusion time will have the solution running at half the normal rate to allow the pancreas to adjust insulin/glucagon secretion to prevent hypo-or hyperglycemia. To calculate these rates divide the total volume of TPN/day by the number of hours for infusing minus one to obtain the rate of infusion during the main period of infusion. One half that rate is the step-up and step-down rate. Running D10% solution or other fluid should be unnecessary if the patient has been gradually tapered to this regimen from a 24-hour infusion protocol. Infuse other IV fluids over the remaining 6-8 hours or TKO with the TPN fluid (10 ml/hour).

References:

*General Guidelines for TPN*