Clinical Nutrition

part I

Jacek Szopinski MD. PhD

Department of General Surgery and Transplantology

Collegium Medicum in Bydgoszczy,

Nicolaus Copernicus University in Torun, Poland

Supply of energy, proteins, electrolytes, trace

elements and vitamins in the form of intravenous

fluids or intra-GI tract formulae to the patients

who are not able to eat normally due to the main

disease or/and its complications

+ the new discipline of medicine

CLINICAL NUTRITION

Nutritional requirement

• Nutrients are substances that are not synthesized in

the body in sufficient amounts and therefore must

be supplied by the diet

Nutritional requirements:

Macronutrients: carbohydrates, proteins, fat

Micronutrients: vitamins, minerals, trace elements

Water

The completeness rule

• Providing clinical nutrition we should

always supply ALL nutrients (macro-,

micro- and water)

so, glucose infusion

IS NOT NUTRITION !

basic rule of clinical nutrition

Malnutrition

Malnutrition

Simple

starvation

Stress starvation

Lack of nutrients

= undernutrition

Malnutrition

Simple starvation

hunger strikers

anorexia nervosa

neurological diseases

(Parkinson, SLA, dementia, stroke)

most of cancer patients in the

begining of the disease

Simple starvation

Simple starvation

Stress starvation

Stress starvation

Stress starvation

Stress starvation

Stress starvation

Physiological results of

malutrition • loss of body weight (loss of the mass of organs,

tissues)

• loss of muscle mass – musle weakness,

immobility (sitting, laying) – progress of muscle

loss – poor lung ventilation – peumonia

• worsening of the function of different organs –

organ insufficiency

Physiological results of

malutrition • low albumin concentration (transport !)

• low Fe, low vitamin B12, low proteins – anemia

• no energy / structure nutrients for syntheis

especially immunological system

- less immune cells (leukocyte CD4, CD 8)

- less antibodies (Ig G,M,A)

Physiological results of

malutrition

FROM CLINICAL POINT OF VIEW

severe undernutrition = severe immune deficiency

Physiological results of

malutrition

• less lympoid tissue – GALT (gut associated

lymphoid tissue)

– 70 % of the mass of limphoid tissue of the body;

- sensitive to food antigenes

– if no food i the GI tract – apoptosis

GALT (Gut Associated Lymphoid Tissue)

Physiological results of

malutrition

• dysfunction of the mucosa of the GI tract –

(enterocytes are fed from circulating blood in 50 % and

directly from the lumen of GI tract in 50% -

if no food = edema of enterocytes = loss of intercellular

connections = loss of adhesion proteins = loss of

mucosal villi )

72 hrs fasting

Physiological results of

malutrition • loss of GI tract integrity

+ low acid output in the stomach

+ GALT apoptosis

+ increase of bacterial toxicity

= bacterial

translocation

„Trophic nutrition”

• Enteral nutition with small amounts of enteral

formula used with intention to „feed” musosa

of GI tract

• The amount used is not enough to provide

daily energy / nutrients demand of the whole

body

Diagnosis of malutrtion….

or better:

estimation of nutritional status

Malnutrition

And malnutrition …

Screening tools

• NRS 2002 (Nutritional Risk Screening)

• MUST (Malnutrition Universal Screening

Tool)

Diagnostic tools

• SGA (Subjective Global Assessment of

Nutritional Status )

Estimation of nutritional status

• Anthropometry (BMI, midarm circumference)

• Biochemistry (plasma albumin, prealbumin

whole protein, transferrin, number of limphocytes)

• Anamesis (diet analysis, weight loss)

• Dynamic measures (handgrip dynamometry)

Malnutrition BMI

Anthropometry

MAC MidArm Circumference

at the not domiating extremitty

half of the length of arm

betten than BMI in older people !

Anthropometry

TSF Triceps Skinfold Thickness

3 measurements – average

not precise: mistakes 20 %

MAC(cm) – (3,14 x TSF mm)

Anthropometry

DEXA Dual-energy X-ray absorptiometry

Anthropometry

BIA bioelectrical impedance analysis

Biochemistry

• ALBUMIN

in the onset of the disease

not in renal/liver insufficiency

better indicator of the general status of the

patient and pronosis than nutrition !

T1/2 21 days

Biochemistry

• TRANSFERRIN

T1/2 7 days

less in the whole body

Fe dependent

Biochemistry

• PREALBUMIN

T1/2 2 days

good indicator of changes in nutritional

status

BLOOD MORPHOLOGY

• LYPHOCYTE COUNT

Norm: > 1,5 tys. / 1 mm3

1,2 – 1,5 slight malnutrition

0,8 – 1,2 moderate malnutrition

<0,8 severe malnutrition

• Handgrip dynamometry

Estimation of nutritional status

• Weight loss in time (10-15% in 3-6 mths)

• BMI

• Plasma albumin

• Plasma prealbumin

• Whole protein

• Transferrin

• Number of lymphocytes

SEVERE NUTRITIONAL RISK

• Weight loss > 10% / 3 months

or > 15% / 6 months

OR

Albumin < 3.0

OR

BMI < 18.5 kg/m2

Essential nutrient requirement

Stable weight:

energy intake ≈ energy output

Essential nutrient requirement

Sources of energy expenditure

► Resting Energy Expenditure (REE)

► Activity Energy Expenditure (AEE) Major

► Others: - energy for mobilizing food

- shivering thermogenesis Minor

Energy

Fuel: carbohydrates, fat, proteins, O2

Waste products: CO2

C6H12O6 + O2 = 6H2O + 6CO2 – 2,8 MJ

Direct calorimetry: measures heat changes

Indirect calorietry: measures O2 and CO2

Resting Energy Expenditure (REE)

• This is energy needed to maintain the

heart, lung, work for synthesis of new

chemical bonds & for maintaining

electrochemical gradient in cells.

• This requires 22kcal/kg/day averagely.

• Can be measured by calorimetry or

using Harris- Benedict equation

Indirect calorimetry

Harris – Benedict equation

Men

BMR = 88.362 + (13.397 x weight in

kg) + (4.799 x height in cm) - (5.677

x age in years)

Women

BMR = 447.593 + (9.247 x weight in

kg) + (3.098 x height in cm) - (4.330

x age in years)

Average Energy Intake

• Men:2800 kcal/day Varies based on

• Women: 1800 kcal/day body size/activity

Increase of energy expenditure

• Fever (13% / 1o C)

• Chills 100 %

• Visit of relatives 40 %

• Respiration 25 %

• Food intake 9 %

• Katecholamines 30 %

Decrease of energy expenditure

• Hypothermia (13% / 1o C)

• Muscle relaxants 40 %

• Analgetics 50 %

• Respiratory vent. 20 %

• Fasting 10-20 %

• B- blockers 25 %

Resting Energy Expenditure (REE)

Multiply REE by the following factors when

patient is stressed:

• Post-operation (REE x 1)

• Metastatic cancer (REE x 1.2)

• Intra-abdominal sepsis (REE x 1.3)

• Severe sepsis (REE x 1.4)

• Acute disease, postoperative phase

20 – 25 kcal / kgBW

• Anabolic phase

25 – 30 kcal / kgBW

• Severe malnutrition

30 – 35 kcal / kgBW

Clinicaly useful energy reqiurement

How much energy?

25 kcal/kg IBW

30 kcal/kg IBW

35 kcal/kg IBW

Perioperatively Burns

Sepsis

Repeted surgery

GI 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. 9

high 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

• To be continued ….. see part 2