Clinical Nutrition

part II

Jacek Szopinski MD. PhD

Department of General Surgery and Transplantology

Collegium Medicum in Bydgoszczy,

Nicolaus Copernicus University in Torun, Poland

How much energy?

25 kcal/kg IBW30 kcal/kg IBW

35 kcal/kg IBW

Perioperatively BurnsSepsis

Repeted surgeryGI fistula

Obesity

20 kcal/kg IBW

Severe malnutrition

What is nutrition support?

• An alternate means of providing nutrients to people who cannot eat any or enough food

• When is it needed?– Illness resulting in inability to take in adequate nutrients by

mouth– Illness or surgery that results in malfunctioning gastrointestinal

tract

• Two types:– Enteral nutrition– Parenteral nutrition

Nutrition route

ENTERAL route always preferable unless contraindications:• mechanical ileus,• severe shock (non-stabilized),• bowel ischemia (even suspected only)

IF the enteral route NOT POSSIBLE or at least 60% of daily energy intake can not be acheived -> MIXED ENTERAL AND PARENTERAL NUTRITION

PARENTERAL route alone

Methods of enteral feeding

• Sip feeding • Tube feeding• Nasoenteral tube• Tube enterostomy• Percuteneous endoscopic jejunostomy

(PEG)• Fine catheter needle jejunostomy

Sip feeding / oral nutritional supplements (ONS)

Oral nutritional supplements

• protein rich (ie. Nutridrink Protein 125 ml)

before major non – cancer surgery

(2x daily/ 5 x days)

• with immunonutrition (i.e. Cubitan, Impact Enteral) contain: ARG, GLU, nucleotides

(2x daily / 5-7 days)

Enteral feeding“If the gut works – use it”

• Nasogastric (NG)

• Nasojejunal (NJ)

• Percutaneous Endoscopic Gastrostomy (PEG)

• Percutaneous Endoscopic Jejunostomy (PEJ)

• Radiologically Inserted Gastrostomy (RIG)

• Surgical Gastrostomy

• Surgical Jejunostomy (JEJ)

Nasoenteric tube

PEG or G-tube

PEG (Percutaneous Endoscopic Gastrostomy)

G-tube (gastric tube)

Microjejunostomy

1. Whole protein formulae (polymeric)- contain intact proteins, and usually include lipids in the form of long chain triglycerides (LCTs), and carbohydrates predominantly as maltodextrins; - require relatively normal gastrointestinal function for digestion and absorption, but can be used successfully in up to 95% of patients on artificial enteral nutrition;- nutrients are not hydrolysed - osmolality reasonably close to the physiological level (about 200 to 350 mosmol/kg).

2. Peptide – based formulae (oligomeric) - partially "pre-digested" and are thus more easily absorbed than whole protein formulae. - contain nitrogen predominantly in peptide form (chains of 2-50 amino acids). - lipids are provided at least in part as MCTs, since these also are more readily digested and absorbed.

3. Free amino acid formulae (monomeric) contain single amino acids as the nitrogen source; very few indications for their use, since oligopeptides are generally better absorbed than free amino acids and combine this with lower osmolality.

EN Standard formula

standard energy 0.9 – 1.2 kcal / ml low energy < 0. 9high energy > 1. 2

Indications for monomeric formulae

Some forms of congenital metabolic disease,Severe allergy to dietary protein,Nutritional treatment of Crohn's disease

Protein sources for the whole protein formulae are mostly milk proteins such as casein, often together with soy proteins. In peptide-based formulae hydrolysates of soy, lactalbumin, gelatine and/or whey are used. Amino acid-based formulae contain free amino acids, and accordingly do not contain glutamine, because this amino acid is not stable in its free state.

Fat sources in standard formulae are predominantly mixtures of oils that are high in polyunsaturated ω-6 fatty acids, such as sunflower, soy, safflower and corn oils. Recently, with increasing awareness of the positive effects of the ω-3 fatty acids, canola oil has been added to many formulae, and sometimes fish oils are added.Medium chain triglycerides (MCT) derived from coconut oil form part of several formulae. Peptide-based and elemental preparations often contain dominant amounts of MCTs, on the basis that they do not require bile salts or pancreatic lipase prior to absorption, and that they bypass the lymphatic system with direct uptake into the portal circulation. Self-evidently the MCTs do not contain any essential fatty acids, and a minimum of 5% polyunsaturated fatty acids is added to any such mixture in order to ensure that the formula is nutritionally complete.

Enteral formulae

Carbohydrate sources are predominantly partial enzymatic hydrolysates of corn starch (maltodextrins with at least 10 glucose molecules). Some formulae, especially those intended for oral use, may contain small amounts of sucrose as this increases palatability. Some whole protein formulae may also contain starch.

Minerals, vitamins and trace elements are added, usually to meet 100% of each RDA in the volume of the formula required to yield 1500 kcal.

EN formulae generally do not contain lactose, cholesterol, purines, or gluten

This is achieved by careful choice of the base materials rather than through technical elimination processes. Cholesterol, for example, is avoided by the selection of plant oils as the predominant lipid sources. Purines are absent from the principal macro-ingredients (such as milk and soy). Gluten content is minimised by the choice of corn-derived carbohydrates. The protein component of most enteral products is added in highly concentrated powder form, usually with a protein fraction of about 85%; this helps to ensure that only negligible amounts of lactose remain despite the use of milk. Enteral formulae are therefore safe for patients with primary or secondary lactose intolerance, coeliac disease, and appropriate for use in those with gout or hypercholesterolaemia.

Despite their use of manipulated products, enteral formulae are still based on natural components mainly using common high quality staples. Emphasising their artificiality is no more logical than in respect of regular supermarket foods (such as milk desserts), and may be counterproductive when encouraging their use by patients.

Short-Term vs. Long-Term Tube Feeding Access

• No standard of care for cut-off time between short-term and long-term access

• However, if patient is expected to require nutrition support longer than 6-8 weeks, long-term access should be considered

Complications of Enteral Nutrition Support

• Aspiration • Nausea and vomiting (delayed gastric

emptying) • Malabsorption (hyperosmolarity)

– steatorrhea, diarrhea (most frequent)

Parenteral Nutrition

• This is administering nutrients through the vein

• AIO („All in One” method)• Two types:

– Peripheral– Central

Indications for Total Parenteral Nutrition (TPN)

• All severely ill patients where GIT is not available for feeding.– Protein calorie malnutrition– Intra-abdominal sepsis– Sever trauma

• It is used when the GIT is blocked, short, fistulated, inflamed or cannot cope with demands.

Indications for Total Parenteral Nutrition (TPN)

• GIT is:• Blocked - Gastric outlet obstruction• Short - Short bowel syndrom• Fistulated - proximal enterocutaneous fistula.• Inflamed – inflammatory bowel disease• Unable to cope – severe trauma

Central vein access

Central vein access

The end of the catheter

lower 1/3 vena cavaupper 1/3 right atrium

X-ray !

• CVC port

Silicone membrane (up to 2000 injections)

Ceramic base

amino acids always 8 obligatory amino acids: (izo, leu, liz, met, fen,

tre, try, wal)+ non obligatory amino acids

total amount: 12-16 g/ldaily requirement for healthy adults: 0.75 /kg BWdaily requirement for patients: 1.0 – 1.5 / kg BW

Proteins

Glucose one of 2 main energy sources (4 kcal/g) usually 50-70 % of energy lowers the level of gluconeogenesis, regulates

metabolism of amino acids and lipids

Max dose 5 mg/kg/min

produced CO2

RQ (Respiratory Quotient) = _____________

used O2

RQ glucose = 1.0 RQ lipids = 0.7

Carbohydrates

Maintain plasma glucose < 150 mg/dl

soybean fatty acids (LCT)source of energy (1 g = 9 kcal) and obligatory fatty acids (linoleic acid, alpha-linolenic acid)

phospholipids – structure of the cell membrane 25-50 % energy 0.1 g/kg/h (LCT)

or 0.15 g/ kg/ h (MCT/LCT)

stop infusion if hipertrigliceridemia (> 350 mg/dl)able to modify inflammation:MCT, olive oil, fish oil

Lipids

9 water soluable vitamins + 4 lipid soluable

obligatory for metabolism of proteins, lipids and carbohydrates – coenzymes, regulatory functions,

antioxidants for free radicals ALL vitamins should be given from the very begining

(50% pts shortage of vitamins D, folic acid, E, A, H) administration of some vitamins modifies the need for

others (ie. ↑ C -- ↑ B2 i B12)

Solutions: Soluvit, Cernevit (water sol.) Vitalipid (lipid sol.)

Vitamins

All electrolytes should be administered to fulfil daily requirements and losts

The amino acids solutions contain electrolytes Can be added separately if necessary

NaCl, KCl, CaCl2, Ca gluconate, Phosphate

Solutions: Glycophos, Addiphos

Limitted amout in the All in One bags !!!

Electrolytes

AIO (”All in One” bags)

AIO

1+ ions: Na + K < 130 mmol/l2+ ions: Ca + Mg < 8 mmol/l

CAN (Critical Aggregation Number a maximal concentration of cations above which the aggregation of lipid particles can occur

1+ ions + 64 x 2+ ions + 729 x 3+ ions < 600 /l

CaHPO4 - unsoluable

Ca3PO4 - unsoluable

2+ ions => 60x more destabilizing effect of a monovalent ions

Precipitation of Calcium Hydrogen Phosphate. The sediment is deposited when the product of concentration of Ca2+ and ions is above 72 mmol2/L. Many other factors such as pH and the content of the mixture, the way it was prepared, and storage conditions may affect the solubility of CaHPO4. Currently, the risk of precipitation of CaHPO4 can be eliminated by the use of organic calcium salts such as gluconates and glycerophosphate which do not dissociate in aqueous solutions

Inactivation of Vitamins, as They Are Highly Susceptible to Degradation. Parenteral nutrition generally contains vitamins at the minimal concentrations necessary for the body function. Sometimes the clinical state of the patient requires additional supplementation with high doses of some vitamins: vitamin B1 in severe malnutrition or vitamin C in patients with increased cell catabolism. Inactivation of vitamins may follow many mechanisms: photolysis of vitamin A and B1, oxidation of vitamin C, reduction of vitamin B1, or adsorption of vitamin A onto the surface of the container

Immunonutrition

Recently - some advantages of specific components for patients’ survival and lowering the number of complications (several trials, some still ongoing) glutamine, arginine, nukcleotydes, ώ- 3 fatty acids

GLUTAMINE (Dipeptiven) – elevating the number and activity of limphocytes and the cytotoxic activity of mononuclears; obligatory AA for fast proliferating cells strong indications (grade A) in severe burn and trauma daily dose in critically ill: 0,3-0,6 g/kg

OMEGA 3 FATTY ACIDS (Omegaven) – immunosupresive effect

(lower cytokine production, lower the expression of Tcell activating receptors) lower inflammatory response (support CARS) max 30 % of daily lipid

PPN vs. TPN

• TPN (total parenteral nutrition)– High glucose concentration (15%-25% final dextrose

concentration)– Provides a hyperosmolar formulation (1300-1800 mOsm/L)– Must be delivered into a large-diameter vein through central

line. • PPN (peripheral parenteral nutrition)

– Similar nutrient components as TPN, but lower concentration (5%-10% final dextrose concentration)

– Osmolarity < 900 mOsm/L (maximum tolerated by a peripheral vein)

– May be delivered into a peripheral vein– Because of lower concentration, large fluid volumes are

needed to provide a comparable calorie and protein dose as TPN (practically up to 2000 kcal/24h)

Administration of the Nutrient Solution

• The hypertonic solution is given at a constant rate per day (usually 1-1.5liters in 1st 24hrs then 1liter 12hourly x 48hrs increasing up to 2.5liters/day gradually to avoid hyperosmolarity problems.

Parenteral Nutrition Monitoring

• Check daily electrolytes and adjust TPN/PPN electrolyte additives accordingly

• Check accu-check glucose q 6 hours (regular insulin may be added to TPN/PPN bag for glucose control as needed) – Non-diabetics or NIDDM: start with half of the previous day’s sliding

scale insulin requirement in TPN/PPN bag and increase daily in the same manner until target glucose is reached

– IDDM: start with 0.1 units regular insulin per gram of dextrose in TPN/PPN, then increase daily by half of the previous day’s sliding scale insulin requirement

• Check triglyceride level within 24 hours of starting TPN/PPN– If TG >250-400 mg/dL, lipid infusion should be significantly reduced

or discontinued– Consider adding carnitine 1 gram daily to TPN/PPN to improve lipid

metabolism– ~100 grams fat per week is needed to prevent essential fatty acid

deficiency

Parenteral Nutrition Monitoring(continued)

• Acid/base balance– Adjust TPN/PPN anion concentration to maintain

proper acid/base balance– Increase/decrease chloride content as needed– Since bicarbonate is unstable in TPN/PPN

preparations, the precursor—acetate—is used; adjust acetate content as needed

Complications of Parenteral Nutrition

• Hepatic steatosis (PNALD) – May occur within 1-2 weeks after starting PN– May be associated with fatty liver infiltration– Usually is benign, transient, and reversible in

patients on short-term PN and typically resolves in 10-15 days

– Limiting fat content of PN and cycling PN over 12 hours is needed to control steatosis in long-term PN patients

Complications of Parenteral Nutrition Support (continued)

• Cholestasis– May occur 2-6 weeks after starting PN– Indicated by progressive increase in TBili and an elevated serum

alkaline phosphatase– Occurs because there are no intestinal nutrients to stimulate

hepatic bile flow– Trophic enteral feeding to stimulate the gallbladder can be

helpful in reducing/preventing cholestasis• Gastrointestinal atrophy

– Lack of enteral stimulation is associated with villus hypoplasia, colonic mucosal atrophy, decreased gastric function, impaired GI immunity, bacterial overgrowth, and bacterial translocation

– Trophic enteral feeding to minimize/prevent GI atrophy

Benefits of Enteral NutritionOver Parenteral Nutrition

• Cost– Tube feeding cost ~ $10-20 per day – TPN costs up to $100 or more per day!

• Maintains integrity of the gut– Tube feeding preserves intestinal function; it is more physiologic– TPN may be associated with gut atrophy

• Less infection– Enteral feeding—very small risk of infection and may

prevent bacterial translocation across the gut wall– TPN—high risk/incidence of infection and sepsis

Refeeding Syndrome

• “the metabolic and physiologic consequences of depletion, repletion, compartmental shifts, and interrelationships of phosphorus, potassium, and magnesium…”

• Severe drop in serum electrolyte levels resulting from intracellular electrolyte movement when energy is provided after a period of starvation (usually > 7-10 days)

• Physiologic and metabolic sequelae may include:– EKG changes, hypotension, arrhythmia, cardiac arrest– Weakness, paralysis– Respiratory depression– Ketoacidosis / metabolic acidosis

Refeeding Syndrome (continued)

• Prevention and Therapy– Correct electrolyte abnormalities before starting

nutrition support– Continue to monitor serum electrolytes after

nutrition support begins and replete aggressively– Initiate nutrition support at low rate/concentration

(~ 50% of estimated needs) and advance to goal slowly in patients who are at high risk

Consequences of Over-feeding

• Risks associated with over-feeding:– Hyperglycemia– Hepatic dysfunction from fatty infiltration– Respiratory acidosis from increased CO2 production– Difficulty weaning from the ventilator

• Risks associated with under-feeding:– Depressed ventilatory drive– Decreased respiratory muscle function– Impaired immune function– Increased infection

Thank you