Total Total Parenteral Parenteral NutritionNutritionByByMohammed IsraruddinMohammed Israruddin

Def.Def. :a method of feeding patients by :a method of feeding patients by infusing a mixture of all necessary infusing a mixture of all necessary nutrients into the circulatory system, nutrients into the circulatory system, thus bypassing the GIT.thus bypassing the GIT.

Also referred to as:Also referred to as: intravenous nutrition,intravenous nutrition, parenteral alimentation, andparenteral alimentation, and artificial nutrition.artificial nutrition.

The gut should always be the preferred The gut should always be the preferred route for nutrient administration.route for nutrient administration.

Therefore, parenteral nutrition is Therefore, parenteral nutrition is indicated generally when there indicated generally when there is is severe gastro-intestinal severe gastro-intestinal dysfunction dysfunction (patients who cannot (patients who cannot take sufficient food or feeding take sufficient food or feeding formulas by the enteral route) . formulas by the enteral route) .

Categories of PNCategories of PN

If enteral feeding isIf enteral feeding is completely stoppedcompletely stopped or or ineffective,ineffective, Total Parenteral NutritionTotal Parenteral Nutrition is is used (TPN).used (TPN).

If enteral feeding is justIf enteral feeding is just “not enough”“not enough” , , supplementation withsupplementation with Partial Parenteral Partial Parenteral NutritionNutrition (PPN) is indicated(PPN) is indicated..

INDICATIONSINDICATIONS

In well-nourished adults,In well-nourished adults, 7 - 10 days7 - 10 days of of starvation with conventional intravenous starvation with conventional intravenous support (using 5% dextrose solutions) is support (using 5% dextrose solutions) is generally accepted. generally accepted. If the period of starvation is to extendIf the period of starvation is to extend beyond beyond this timethis time, , or the patient isor the patient is not well-nourishednot well-nourished, , Total Parenteral Nutrition (TPN) is necessary Total Parenteral Nutrition (TPN) is necessary to prevent the potential complications of to prevent the potential complications of malnutrition.malnutrition.

Indications for TPNIndications for TPN Short-term useShort-term use

Bowel injury, surgery, Bowel injury, surgery, major trauma or burnsmajor trauma or burnsBowel disease (e.g. Bowel disease (e.g. obstructions, fistulas)obstructions, fistulas)Severe malnutritionSevere malnutritionNutritional preparation prior to surgery. Nutritional preparation prior to surgery. Malabsorption - bowel cancerMalabsorption - bowel cancerSevere pancreatitisSevere pancreatitisMalnourished patients who have high risk Malnourished patients who have high risk of aspirationof aspiration

Long-term use (HOME PN)Long-term use (HOME PN)Prolonged Intestinal FailureProlonged Intestinal FailureCrohn’s DiseaseCrohn’s DiseaseBowel resectionBowel resection

Nutritional RequirementsNutritional Requirements

Energy: GlucoseEnergy: Glucose LipidLipid

Amino acids (Nitrogen)Amino acids (Nitrogen)Water and electrolytesWater and electrolytesVitaminsVitaminsTrace elementsTrace elements

Requirements:Requirements:EnergyEnergyHospitalized adults require approximately Hospitalized adults require approximately 25-30 25-30

kcal/ kg/day.kcal/ kg/day.However, these requirements may be However, these requirements may be greatergreater in in

patients with patients with injuryinjury or or infection.infection.

Energy RequirementsEnergy Requirements

Patient conditionPatient condition Basal Basal metabolic metabolic

raterate

Approximate energyApproximate energyRequirementRequirement(kcal/kg/day) (kcal/kg/day)

No postoperativeNo postoperativecomplications, GITcomplications, GITfistula without infectionfistula without infection

NormalNormal 25-3025-30

Mild peritonitis, long-bone Mild peritonitis, long-bone fracture, mild to moderate fracture, mild to moderate injury, malnourishedinjury, malnourished

25% above 25% above normalnormal

30-3530-35

Severe injury or infectionSevere injury or infection 50% above 50% above normalnormal

35-4535-45

Burn 40-100% of total body Burn 40-100% of total body surfacesurface

Up to 100% Up to 100% above normalabove normal

45-8045-80

Requirements:Requirements:Energy Sources: Energy Sources: GlucoseGlucose

The most common source of parenteral energy supply The most common source of parenteral energy supply is is glucoseglucose, being:, being: Readily metabolized in most patients,Readily metabolized in most patients, provides the obligatory needs of the substrate , thus provides the obligatory needs of the substrate , thus

reducing gluconeogenesis and sparing endogenous reducing gluconeogenesis and sparing endogenous protein.protein.

1 gm of glucose gives 4 Kcals.1 gm of glucose gives 4 Kcals.

Most stable patients tolerate rates of Most stable patients tolerate rates of 4-5 mg.kg4-5 mg.kg-1-1.Min.Min-1-1, , but insulin resistance in critically ill patients may lead but insulin resistance in critically ill patients may lead to hyperglycemia even at these rates, so insulin to hyperglycemia even at these rates, so insulin should be incorporated acc. to blood sugar levels.should be incorporated acc. to blood sugar levels.

Requirements:Requirements:

Energy Sources: Energy Sources: GlucoseGlucose

RouteRouteGlucose in Glucose in 5%5% solution can be safely solution can be safely administered via a administered via a peripheral veinperipheral vein, but , but higher higher concentrationsconcentrations require a require a central central venous line. venous line.

20, 25, or even 50 %20, 25, or even 50 % solutions are needed to solutions are needed to administer meaningful amounts of energy to administer meaningful amounts of energy to most patients for proper volume administrationmost patients for proper volume administration..

Requirements:Requirements:Energy SourcesEnergy Sources: Lipid: Lipid

Fat mobilization is a major response to stress and Fat mobilization is a major response to stress and infection.infection.

Triacylglycerols are an important fuel source in Triacylglycerols are an important fuel source in those conditions, even when glucose availability is those conditions, even when glucose availability is adequate.adequate.

Need to be Need to be restrictedrestricted in patients with in patients with hypertriglyceridemia.hypertriglyceridemia.

Requirements:Requirements:Energy Sources: Energy Sources: LipidLipid

Ideally, energy from fat should not exceed Ideally, energy from fat should not exceed 40%40% of the total of the total (usually 20-30%).(usually 20-30%).Fat emulsions can be safely administered via Fat emulsions can be safely administered via peripheral peripheral veinsveins, provide , provide essential fatty acidsessential fatty acids, and are concentrated , and are concentrated energy sourcesenergy sources for fluid-restricted patients. for fluid-restricted patients.They are available in They are available in 10, 20 and 30%10, 20 and 30% preparations. preparations.Though lipids have a calorific value of 9Kcal/g, the value in Though lipids have a calorific value of 9Kcal/g, the value in lipid emulsions is lipid emulsions is 10Kcal/g10Kcal/g due to the contents of glycerol due to the contents of glycerol and phospholipids.and phospholipids.Fat emulsions can be safely administered via Fat emulsions can be safely administered via peripheral peripheral veinsveins, provide , provide essential fatty acidsessential fatty acids, and are concentrated , and are concentrated energy sourcesenergy sources for fluid-restricted patients. for fluid-restricted patients.

Requirements:Requirements:Energy Sources:Energy Sources: LipidLipid

They are available in They are available in 10, 10, 20 and 30%20 and 30% preparations. preparations.

Though lipids have a Though lipids have a calorific value of 9Kcal/g,calorific value of 9Kcal/g, the value in lipid emulsionsthe value in lipid emulsions is is 10Kcal/g10Kcal/g due to the due to the contents of glycerol and contents of glycerol and phospholipids.phospholipids.

Requirements:Requirements:NitrogenNitrogen

Protein requirementsProtein requirements for most healthy for most healthy individuals are individuals are 0.8 g/kg/day0.8 g/kg/day..Critically ill patientsCritically ill patients may need as high as may need as high as 1.5-1.5-2.5 g protein/kg/day2.5 g protein/kg/day depending on the disease depending on the disease processprocess

((major trauma or burn > infection or after surgery > major trauma or burn > infection or after surgery > standardstandard))

Requirements:Requirements:NitrogenNitrogenDaily Protein requirementsDaily Protein requirements

ConditionCondition ExampleExample requirementrequirementBasic requirementsBasic requirements Normal personNormal person 0.5-1g/Kg0.5-1g/KgSlightly increased Slightly increased requirementsrequirements

Post-operative, cancer, Post-operative, cancer, inflammatoryinflammatory

1.5g/Kg1.5g/Kg

Moderately increased Moderately increased requirementsrequirements

Sepsis, polytraumaSepsis, polytrauma 2g/Kg2g/Kg

Highly increased Highly increased requirementsrequirements

Peritonitis, burns, Peritonitis, burns, 2.5g/Kg2.5g/Kg

Reduced requirementsReduced requirements Renal failure, hepatic Renal failure, hepatic encephalopathyencephalopathy

0.6g/Kg0.6g/Kg

Requirements:Requirements:NitrogenNitrogen

Available a.a. preparations Available a.a. preparations are are 3.5 - 15 %3.5 - 15 % (i.e. (i.e. contains 3.5-15 gms of contains 3.5-15 gms of protein or a.a.s/100 mLprotein or a.a.s/100 mL solution).solution).

1gm of protein = 1gm of protein = 0.16 gm0.16 gm of N of N2.2.

Requirements:Requirements:Fluids and electrolytesFluids and electrolytes

20–40 mL/kg - daily – young 20–40 mL/kg - daily – young adultsadults30 mL/kg – daily – older 30 mL/kg – daily – older adultsadultsSodium, potassium, chloride, Sodium, potassium, chloride, calcium, magnesium, and calcium, magnesium, and phosphorus ( as per the phosphorus ( as per the table)table)Daily lab tests to monitor Daily lab tests to monitor electrolyte statuselectrolyte status

Requirements:Requirements:Fluids and electrolytesFluids and electrolytes

NutrientNutrient Requirements (Requirements (/Kg/day)/Kg/day)WaterWater 20-40 mL20-40 mL

SodiumSodium 0.5-1.0 mmol0.5-1.0 mmolPotassiumPotassium 0.5-1.0 mmol0.5-1.0 mmolMagnesiumMagnesium 0.1-0.2 mmol0.1-0.2 mmol

CalciumCalcium 0.05-0.15mmol0.05-0.15mmolPhosphatePhosphate 0.2-0.5mmol0.2-0.5mmol

Chloride/AcetateChloride/Acetate So a to maintain acid-base balance So a to maintain acid-base balance (normally 0.5 mmol for Cl(normally 0.5 mmol for Cl-- , & 0.1mEq for Acetate) , & 0.1mEq for Acetate)

Requirements:Requirements:VitaminsVitamins

These requirements are usually met when standard These requirements are usually met when standard volumes of a nutrient mix are provided.volumes of a nutrient mix are provided.

Requirements:Requirements:Increased amounts of vitamins are usually Increased amounts of vitamins are usually provided to severely ill patients.provided to severely ill patients.Vitamins are either fat soluble (A,D,E,K) or Vitamins are either fat soluble (A,D,E,K) or water soluble (B,C). Separate multivitamin water soluble (B,C). Separate multivitamin commercial preparations are now available commercial preparations are now available for both.for both.

Requirements:Requirements:vitaminsvitamins

Requirements:Requirements:These are These are essential component of the parenteral essential component of the parenteral nutrition regimen andnutrition regimen and may be toxic at high doses.may be toxic at high doses.Iron is excludedIron is excluded, as it alters stability of other ingredients , as it alters stability of other ingredients and is given by separate injection (iv or im).and is given by separate injection (iv or im).

Mineral Mineral Recommended dietary Recommended dietary allowance (RDA) for daily allowance (RDA) for daily

oral intake (mg) oral intake (mg)

Suggested daily Suggested daily intravenous intake intravenous intake

(mg) (mg) Zinc Zinc 15 15 2.5-5 2.5-5

Copper Copper 2-3 2-3 0.5-1.5 0.5-1.5 Manganese Manganese 2.5-5 2.5-5 0.15-0.8 0.15-0.8 Chromium Chromium 0.05-0.2 0.05-0.2 0.01-0.015 0.01-0.015

Iron Iron 10 (males)-18 (females) 10 (males)-18 (females) 3 3

Osmolarity:Osmolarity:

PPN: Maximum of PPN: Maximum of 900 900 milliosmoles / litermilliosmoles / liter

TPN: as nutrient dense as necessary TPN: as nutrient dense as necessary (>900(>900 m.osmol and up as high as m.osmol and up as high as 30003000).).

Amino acids (10 m.osmol/gm), dextrose (5 Amino acids (10 m.osmol/gm), dextrose (5 m.osmol/gm) and electrolytes (2 m.osmol m.osmol/gm) and electrolytes (2 m.osmol /mEq) contribute most to the osmolarity, while /mEq) contribute most to the osmolarity, while lipids give 1.5 m.osmol/gm.lipids give 1.5 m.osmol/gm.

Application:Application:The SolutionThe Solution

Manually mixed in hospital pharmacy or Manually mixed in hospital pharmacy or nutrition-mixing service,nutrition-mixing service,

premixed solutions,premixed solutions,

Separate administration for every element Separate administration for every element alone in a separate line.alone in a separate line.

Application:Application:Venous accessVenous access

PPNPPN: (<900 m.osmol/L): a : (<900 m.osmol/L): a peripheral lineperipheral line can be can be enough.enough.TPNTPN: : Central venous access is fundamentalCentral venous access is fundamental,,

Ideally, the venous line should be usedIdeally, the venous line should be used exclusively for parenteral nutrition.exclusively for parenteral nutrition. Catheter can be placed via the Catheter can be placed via the subclaviansubclavian vein, the vein, the

jugularjugular vein (less desirable because of the high rate vein (less desirable because of the high rate of associated infection), or a of associated infection), or a long catheter placed in long catheter placed in an arm veinan arm vein and threaded into the central venous and threaded into the central venous system (a peripherally inserted central catheter line) system (a peripherally inserted central catheter line)

Once the correct position of the catheter has been Once the correct position of the catheter has been established (usually by X ray), the infusion can established (usually by X ray), the infusion can begin.begin.

Application:Application:Initiation of TherapyInitiation of Therapy TPN infusion is usually initiated at a rate of TPN infusion is usually initiated at a rate of 25 to 50 25 to 50

mL/hmL/h. This rate is then increased by 25 mL/h until the . This rate is then increased by 25 mL/h until the predetermined final rate is achieved.predetermined final rate is achieved.

AdministrationAdministration To ensure that the solution is administered at a To ensure that the solution is administered at a

continuous rate, an continuous rate, an infusion pumpinfusion pump is utilized to is utilized to administer the solution. In hospitalized patients, infusion administer the solution. In hospitalized patients, infusion usually occurs over 22-24 h/day. In ambulatory home usually occurs over 22-24 h/day. In ambulatory home patients, administration usually occurs overnight (12-16 patients, administration usually occurs overnight (12-16 h).h).

MonitoringMonitoring

Policy: to monitor:Policy: to monitor:1-1- EffecacyEffecacy: electrolytes (S. Na, K, Ca, Mg, Cl, : electrolytes (S. Na, K, Ca, Mg, Cl,

Ph), acid-base, Bl. Sugar, body weight, Hb.Ph), acid-base, Bl. Sugar, body weight, Hb.2- 2- ComplicationsComplications: ALT, AST, Bil, BUN, total : ALT, AST, Bil, BUN, total

proteins and fractions.proteins and fractions.3- 3- General:General: Input- Output chart. Input- Output chart.4- 4- Detection of infection:Detection of infection: Clinical (activity, temp, symptoms)Clinical (activity, temp, symptoms) WBC count (total & differential)WBC count (total & differential) CulturesCultures

MonitorinMonitoringg

Complications of TPNComplications of TPN

SepsisSepsisPneumothoraxPneumothoraxAir embolismAir embolismClotted catheter lineClotted catheter lineCatheter displacementCatheter displacementFluid overloadFluid overloadHyperglycemiaHyperglycemiaRebound HypoglycemiaRebound Hypoglycemia

HOME PARENTERAL NUTRITIONHOME PARENTERAL NUTRITIONPatients who are unable to eat and absorb adequate Patients who are unable to eat and absorb adequate nutrients for maintenance over the long term may be nutrients for maintenance over the long term may be candidates for home parenteral nutrition e.g. extensive candidates for home parenteral nutrition e.g. extensive Crohn's disease, mesenteric infarction, or severe Crohn's disease, mesenteric infarction, or severe abdominal trauma. abdominal trauma.

patients must be able to master the techniques patients must be able to master the techniques associated with this support system, be motivated, associated with this support system, be motivated, and have adequate social support at home.and have adequate social support at home.

HOME PARENTERAL NUTRITIONHOME PARENTERAL NUTRITIONA patient who is judged to be a candidate for A patient who is judged to be a candidate for home parenteral nutrition requires an indwelling home parenteral nutrition requires an indwelling Silastic catheter designed for long-term Silastic catheter designed for long-term permanent use.permanent use.

The nutrient solutions are prepared weekly and The nutrient solutions are prepared weekly and delivered to the patient's home. delivered to the patient's home.

The patient sets up the infusion system and The patient sets up the infusion system and attaches the catheter to the delivery tubing in attaches the catheter to the delivery tubing in the evening for infusion over the next 12-16 h. the evening for infusion over the next 12-16 h. The intravenous nutrition is terminated by the The intravenous nutrition is terminated by the patient the next morning.patient the next morning.