02 sobotka how

Energy balance

Nutritional Screening and Assessment

Lubos SobotkaCharles University - Medical Faculty

Hradec KraloveCzech Republic

Learning Objectives

To the principles of measurement of energy expenditure

To now how to diagnose a risk of malnutrition

To know the methods for measurement of body composition

To be able to estimate energy intake in hospitalized patients

Flow of energy in biosphere

H2O + CO2

ATPphotosynthesis

CHOFatProteins

N

H2O + CO2

+N

O2 O2

Energy expenditureFOOD

O2

CO2H2ONitrogen

CHOFatProteins

HeatBODY RESERVES

Total energy expenditure - TEE

resting energy expenditure - REE

diet induced energy expenditure - DEE

activity induced energy expenditure - AEE

Resting energy expenditure ∼ 60-70%

Diet induced energy expenditure ∼ 10%

Activity induced energy expenditure ∼ 60-70%

Components of energy expenditure-adult person-

Maintaining cell membrane ion gradientsConstant protein synthesis and breakdownAmino acid metabolism Glycogen synthesis and breakdown Fatty acids cycleGluconeogenesisEnergy for breathing and heart function

An postprandial increase in EE above basal fasting levelLasts for several hours after meal

Is the most variable component of TEEDependent on physical activity

Energy expenditure measurement

Direct calorimetry

Measurement of heat produced during energy processes

Indirect calorimetry

Measurement: O2 consumptionVO2 production

Direct calorimetry

Whole body heat production

Special chambers difference in heat coming into and out of the chamber

T1

T2

V

V

EE ∼ ∆Q = V (T2 – T1)


Measurement of O2 consumption VO2

production

cO2, cCO2

V

VcO2, cCO2

EE ∼ VO2 consumption and VCO2 production


flow

gasmeter

CO2-analyser

O2-analyser

² CO 2 ² O 2outdoor air

outdoor air

respiratory air

ventilated hood or

respiration chamber

Westerterp K, Schols A Basics in Clinical Nutrition, 2004

Ventilated hood - canopy


VO2 = 0.829 CHO + 2.02 Fat + 6.04 NitrogenVCO2 = 0.829 CHO + 1.43 Fat + 4.84 Nitrogen

Substrate oxidation:CHO = 4.59 VCO2 – 3.25 VO2 – 3.68 NitrogenFat = 1.69 VO2 – 1.69 VCO2 – 1.72 NitrogenProtein = 6.25 Nitrogen

Energy expenditure:EE = 3.87 VO2 + 1.19 VCO2 – 5.99 N


Energy expenditure can be calculated both from VO2 and VCO2:

Calculation from VO2 and VCO2:EE = 3.95 VO2 + 1.11 VCO2

Calculation from VO2:EE = VO2 (3.95 + 1.11 RQ) – moderately dependent on RQ

Calculation from VCO2:EE = VCO2 (1.11 + 3.95/RQ) – Highly dependent on RQDoubly labeled water, labeled bicarbonate

80,0

85,0

90,0

95,0

100,0

105,0

110,0

115,0

120,0

0,7 0,75 0,8 0,85 0,9 0,95 1

RQ

Diff

eren

ce in

RE

E [%

]

VCO2VO2VO2 a VCO2

Relationship between REE and RQ [REE calculation based on VO2 or on VCO2]

REE calculated from VCO2 is more dependent on RQ (possible mistake 15%) then if calculated from VO2 (possible mistake 4%)

Measurement of EE using doubly labeled water

2H 18O2

2H 18OLabels water pool

Labels water and bicarbonate pools

2HHO H 18O CO 18O2

H2OK2 = r H2OCO2+ rK18 = r

K18 - K2 = r CO2

Principle of the doubly labelled water (2H218O) method for the measurement of

carbon dioxide production (rCO2) from the elimination rates of 18O (k18) and 2H (k2). The elimination rate of 2H is a function of water loss (rH2O) while k18 is a function of rCO2 and rH2O.

Westerterp K, Schols A Basics in Clinical Nutrition, 2004

0,00

2,00

4,00

6,00

8,00

10,00

12,00

40 50 60 70 80 90 100 110 120 130 140Heart rate [b/min]

Ener

gy ex

pend

iture

[kca

l/min

.]

Relationship between heart rate and energy expenditure

Relationship between heart rate and energy expenditure –whole group

0

2

4

6

8

10

12

14

75 95 115 135 155 175

Heart rate [b/min]

Ene

rgy

expe

nditu

re[c

al/m

in.]

0

2

4

6

8

10

12

14

16

18

95 105 115 125 135 145 155

Heart rate [b/min]

Ener

gy ex

pend

iture

[cal/

min

.]

Relationship between heart rate and energy expenditure –individual patients

Harris-Benedict equations

The most common approach to predict resting energy expenditure

Male: REE = 66.5 + (13.8 x weight) + (5.0 x height) - (6.8 x age)

Female: REE = 655.1 + (9.6 x weight) + (1.8 x height) - (4.7 x age)

The theoretical reserves of a 74 kg man

Body substrate Substrate weight( kg )

Energy content( kcal )

Fat 15 141.000Protein 12 48.000Glycogen (muscle) 0.5 2000Glycogen (liver) 0.2 800

Total 191.800

Prevalence of undernutrition• Ambulatory outpatients 1-15%• Institutionalized patients 25-60%• Hospitalized patients 35-65%

• These rates depend on how malnutrition is defined

Omran et al, Nutrition 2000

Assessment of

Nutritional status

1. Screening

2. Assessment

ESPEN Guidelines for Nutrition Screening

• All patients should be screened on admission to the hospital

• If the patient is at risk, a nutrition plan is worked out by the staff

• Monitoring and defining outcome has to be organized

• Results of screening, assessment and nutrition care plans should be communicated to healthcare professionals to which the patient is transferred

• Outcome should be audited and communicated to furnish the data on which future policy decisions can be made

Nutrition Screening 2002, Clin Nutr 2003www.espen.org → Education → Guidelines

Nutritional screening

Is a tool to rapidly and simplyevaluate whether the patient is at risk to be or to becomemalnourished

Nutritional screening

History:• Weight loss over time• Anorexia, nausea• Food intakeFirst measurements:• Body weight• Height

BMI (kg/m2)

Screening tools• Nutritional Risk Index1 - biochemical• Subjective global assessment2

• Malnutrition Universal Screening Tool (MUST)3

• Nutritional Risk Screening (NRS 2002)4

• MNA (elderly)5

1 Veterans Affairs, New Engl J Med 1991

2 Detsky et al, JPEN, 1984

4 Kondrup et al, Clin Nutr 2003

5 Vellas et al, Nutrition 1999

3 BAPEN

Nutritional risk screeningSubjective global assessment (SGA)

I Patient‘s history(weight loss, change in dietary intake, gi-symptoms,functional capacity)

IIPhysical examination(muscles, subcutaneous fat, edema, ascites)

Clinician‘s overall judgment• good nutritional status• moderate malnutrition• severe malnutrition

Detsky et al, JPEN, 1984

ESPEN guidelines for nutrition screening 2002

Part 1

Kondrup J et al. ESPEN guidelines for nutrition screening 2002. Clin Nutr 2003

Part 2

Kondrup J et al. ESPEN guidelines for nutrition screening 2002. Clin Nutr 2003

Nutritional Assessment

Is the actual measurement of nutritional state and has to be donein patients that are considered to be atrisk by the nutritional screening

orwhen metabolic or functional problemsprevent a standard plan being carried out

Normal body composition

• Normal body cell mass (BCM) is the major determinant of an adequate nutritional state: – Living, actively metabolizing part of the body– Extra-cellular mass may increase

disproportionately in malnutrition, disease, whereas fat free cell mass decreases

• Normal macronutrients, electrolytes, trace-elements, vitamins

• Normal organ sizes

What can be measured?

• Fat body massBody fat percentageFat distribution (visceral fat)

• Lean body massWater: extra and intracellularBody cell massMuscle massBone

The two compartments model

Fat mass

Fat free body mass

The four compartments model

Fat mass

Fat free body mass

• body cell mass• extra-cellular water

• bone

Body composition changes in normal adult males

Body fat (kg)Muscle (kg)Age (years)

152420-29

192040-49

231760-69

251370-79

Young 1992

Underwater weighing

Fat mass Fat-free mass

Dilution method – deuterium/bromide

Deuterium –TBW

Bromide-ECV

Anthropometry

Muscle-mass

Fat-mass

Anthropometry

Anthropometric measurement

• Validation only partially performed• Large inter-individual variability• Good intra-individual variability if the investigator is properly trained

Creatinine excretion in urine • Creatinine excretion correlates with lean body mass and body weight

• 18-20 kg of muscle produce 1 g of creatinine

• Dietary protein sources contribute up to 20% of excreted creatinine

• Urinary creatinine excretion is proportional to skeletal muscle mass (stable renal function; no dialysis or hemofiltration)

Norm values for urinary creatinineexretion/mg/24h

Norm/men

Urina

ry c

reat

inine

(mg/

24h)

Height (cm)

Norm/women

Urinary creatinine excretion is influenced by:

• Decreasing renal function; oliguric renal insufficiency

• No meat consumption↳ low creatinine excretion

• High meat consumption• High physical activity• Catabolism

– fever– infection– trauma

↳high creatinine excretion• Incomplete 24 h-urine sampling

Body fat distributionand waist circumference

• Measured at the mid-point between the ileac crest and the lower rib

• Correlates strongly with intra-abdominal adipose tissue as assessed by CT and MRI

• Upper body obesity defined as a waist circumference: – ≥ 102 (94) cm for men – ≥ 88 (80) cm for women

Bioelectrical impedance analysis (BIA)

• BIA allows the determination of - Fat-free mass and- Total body water

ESPEN - GUIDELINESBioelectrical impedance analysis

Fat-free mass andTotal body water

1) Review of principles & methods.Clin Nutr 2004; 23: 1226-1243

2) Utilisation in clinical practice.Clin Nutr 2004; 23: 1430-1453

www.espen.org/education

Bioelectrical impedance analysis (BIA)

• BIA allows the determination of - FFM on the basis of TBW measurement

• in subjects without significant fluid and electrolyte abnormalities when using appropriate equations (age, sex, race)

• BIA in subjects at extremes of BMI ranges (16-34 kg/m2) or with abnormal hydration status is not reliable

• Disease almost always includes inflammatory activity (ICW/ECW ratio decreases; TBW increases; BIA unreliable)

Dual energy X-ray absorptiometry (DEXA)

• Three-compartment model

• Fat mass, free-fat mass and bone

• State of hydration may affect results

MRI or CT scan

• Fat mass

Creatinine excretion in urine • Creatinine excretion correlates with lean body mass and body weight

• 18-20 kg of muscle produce 1 g of creatinine

• Dietary protein sources contribute up to 20% of excreted creatinine

• Urinary creatinine excretion is proportional to skeletal muscle mass (stable renal function; no dialysis or hemofiltration)

Muscle strength

Muscle strength• Is a good predictor of outcome:

– In chronic situations:• Aging• Organ failure (renal failure, COPD,

heart failue….

– In acute situations:• Surgery or trauma• Second hit (superimposed infection when already subject to inflammatory activity)

SummaryPractical methods for measuring: Fat mass

• Subcutaneous skin folds measurements

• DEXA• MRI, CT scan• BIA

SummaryPractical methods for

measuring: Fat-free mass

• DEXA• BIA• (Underwater weighing)


measuring: Body cell mass

• (Total body potassium)• (Nitrogen neutron activation)


measuring: Muscle mass

• Mid-arm circumference• Creatinine height index• Urinary 3-Methylhistidine

SummaryPractical methods for measuring: Body-water

• Total body water(- Isotopic labeling of water)- BIA

• Extracellular water(- Bromide space)

SummaryPractical methods for measuring:

Bone mass

• DEXA• Total body calcium-measured

by isotopes methods

Inflammatory and disease activity

Disease always includes inflammatoryactivity• Clinical evaluation

- Pre-existing inflammation or disease • Plasma Albumin levels

- Already significant when ≤ 35 g/L• Cytokine levels (TNF-α, IL 6, ...)• CRP

- Very volatile, is a rough correlations, but notsuitable for the individual patient

Serum proteins

• Albumin (T½): 20 days• Transferrin (T½): 8-10 days• Transthyretin (T½): 2-3 days

(Prealbumin) • Retinol-binding protein (T½): ∼ 12 h

Wound healing is dependent of endogenous substrates

Undernutrition

poor wound healing(dehiscence, infections)

Loss body cell mass

Deficit endogenous substrates for wound

healing.

Complicated surgical wound

Complicated operation wound

Granulation stimulation

Complex treatment

Wound before the last operation

A sterile gauze poured byhyaluronan-iodine complex

Infectious complications and albumin

Kudsk et al, JPEN 2003

How to measure food intake

• Bomb calorimetry of food before and after meal (double plate method)

• Weighing of food before and after meal • Quarter plate method

Quarter plate method

• Standard meal

• 2000 kcal• 60 g protein• 290 g CHO• 70 g fat

Calculate energy and protein intake – he eats ¼ of servings

• Standard meal


Calculate energy and protein intake – he eats ¼ of servings

• Standard meal


• Daily intake

• Energy – 500 kcal• Protein – 24 g

Calculate daily energy balance

• Energy balance EB:

EB = EI – TEE

EB = 500 – 1800 = -1300 kcal/day

Calculate daily need of supplements

• Energy deficit: 1300 kcal/day• Protein deficit: 30.4 g day

Standard supplement (sipping) = 150 kcal & 6 g Prot/100 mlRecommendation = 1000 ml of standard nutrition (e.g. sipping)

Thank you!

Technology

02 sobotka how