ESPEN Leonardo da Vinci



Nutritional assessment and computers.

Pierre Singer

Aim of the lecture:

Understanding of the use of computers in nutrition

Objectives:

Comprehensive description of the patient centered information system

Examples of applications

The patient is generating a very large amount of information and data. With the progress of computerized systems, communication within hospitals is became patient centered and data management is focused on patient diagnostic and therapeutic procedures.

Data + Purpose = Information

Information + Understanding = Knowledge

Knowledge + Conviction = Opinion

Nutritional assessment data should be used for a determined purpose, to reach the maximum of information, for diagnosis or screening for example. When well understood, this information is increasing knowledge’s physicians. This knowledge mixed to a conviction becomes an opinion on a medical condition.

Examples:

Examples can be taken from the energy balance assessment. Datas acquired using computerized information system in the intensive care is able to achieve a very accurate energy balance during the hospitalization. The information of a negative energy balance is better understood when correlation between negative energy balance and complications is found. This knowledge together with the conviction that we should feed ICU patients is raising the opinion that tight calorie balance control is mandatory in the ICU

Others examples using computers have been described in the screening of nutritional status in chronic renal failure patients. Computers have also been used for advising for the best diet in a computer-tailored nutrition intervention.

Conclusions:

The use of computers in nutritional practice is helpful, time sparing and increasing knowledge about the nutritional condition of our patients.

History taking, Physical examination

Sadık Kılıcturgay ,

Aim of the lecture:

To realize the signs and the symptoms of nutritional problems

To understand how important to get the history taking and physical examination on the definition of nutritional problems

To assess a patient for general nutritional status

Objectives:

At the end of the presentation, the student will be able to:

-Obtain the nutritional aspects of patient history assessing nutritional risk factors, including dietary intake and utilization and diseases affecting these processes.

-Perform physical assessments

-Perform Subjective Global Assessment (SGA)

Content of the lecture:

History taking,

Physical examination

About 30-50 % of all patients in hospital are malnourished. A large part of these patients are malnourished when admitted to hospital and in the majority of these, malnutrition develops further while in hospital.This can be prevented if special attention is paid to their nutritional care. The history is the starting point for any nutritional assessment. Specific features of note include a recent weight changes; dietary habits and alteration in dietary intake; allergies and food intolerance; medications that may effect appetite, gastrointestinal functions and symptoms; current functional capacity, including recent limitations; and previous medical conditions (any chronic or acute disease state)

Physical examination is the next step in nutritional assessment. This assessment predominantly relies on subjective and descriptive information. Although not quantitative, a physical examination is may still influence the nutritional management of a patient. The main objective of a physical examination is to establish signs and symptoms of nutrient deficiencies or toxicities, and tolerance of current nutritional support. A systems approach should be applied using the examination techniques of inspection, palpation, percussion, and auscultation. The physical examination should include:

• Assessment of muscle mass and subcutaneous fat stores.

• Inspection and palpation for edema and ascites. These two conditions are important physical indicators of diminished visceral protein levels and hepatic dysfunction.

• Inspection and evaluation for sings and symptoms of vitamin and mineral deficits, such as dermatitis, glossitis, cheilosis, neuromuscular irritability, and coarse, easily pluckable hair.

• The patient’s prescribed medication should be examined for potential drug-nutrient interactions, increased macro-or micronutrient requirements, and nutritionally related side effects such as constipation, diarrhea, nausea vomiting

The simplest validated nutritional assessment is the SGA, whish is based on patient’s history and physical examination. Clinicians prefer SGA because of its simplicity, feasbility and sensitivity that is almost equivalent to objective tests.

Nutritional assessment of patients is not an easy procedure. Although, lots of the clinical and laboratory measurements are available for nutritional assessment, all of them have lots of deficiencies. Nutritional assessment is an art more than science. At the current state of the art, in addition to the physical examination and clinical history, many experienced clinicians solve this problem by using a few laboratory tests.

References and suggested readings

▪ J. Kondrup J, Allison SP, Elia M.,Vellas B, Plauth M.: ESPEN Guidelines for Nutrition Screening 2002. Clinical Nutrition 2003; 22: 415–421

▪ Eisenstein C, Van Way CW.: Nutritional Assessment, in Handbook of Surgical Nutrition, Ed. Charles W.Van Way, First ed. J.B.Lýppýncott Company Philadelphia, 1992;107-119.

▪ Barendregt K, soeters PB, Allison SP.: Diagnosis of malnutrition. Screening and assessment. in Basics in clinical nutrition, second edition Editor in chief Lubos Sobotka Galen, 2000 p: 29-36

▪ David E Carney DE, Meguid MM : Current concepts in nutritional assessment Archives of Surgery;2002; 137: 42-45

Methods of measuring body composition

Nachum Vaisman

Am of the lecture:

To give a comprehensive overview about the components of body composition and the different methods available for their measurement.

Learning objectives:

1. To study the different components of body composition and the models of compartments.

2. To study and understand the specific methods of measurements, their advantages and drawbacks.

3. To learn how these methods can help in clinical situations

Summary

Measurements of body composition are essential to the nutritionist as a tool for evaluating the patient's nutritional status on admission and follow the efficacy of his nutritional intervention on follow-up. Measurements can be made on different levels: atomic, molecular, cellular, tissue or the whole body. In clinical settings, the most used methods include the whole body approach or the tissue-system approach. The latter can be studied in a 2-compartment model or a more detailed one, the 4-compartment approach. The two compartments include the body fat mass (FM) and the fat-free body mass (FFBM). The latter is almost identical to the lean body mass (LBM). The four- compartment approach further breaks down the fat-free mass into three sub-compartments: body cell, extra-cellular water and bone. The different methods of measurement are based on biochemical and physiological characteristics. Some of the methods measure directly the specific component, but others are derived from other measurements, based on specific physiological assumptions. Understanding the background and the rationale behind a method can help in the interpretation of the results. Underwater weighing or air displacement plethysmography can help in obtaining the two compartments: FM and FFBM. MRI and quantitative CT can also measure FM directly. Indirectly, FM can be derived from measurements of 2-4 sites of subcutaneous fat skin folds. FFM and FM as well as the bone can be measured by the DXA (dual energy X-ray absorptiometry) method which uses two levels of X-ray energy and separates the compartments based on the different attenuation of the X-ray energy in a tissue–specific manner. Based on the assumption that cell hydration is constant (73% of the cell) measurements of total body water and its two components: extra cellular and intracellular, can be used to derive FM. Total body water can be studied by isotopic labeling of water (HDO, THO, H2O18) or by the bioelectrical impedance method (BEI). The different components of FFM can be derived

by direct and indirect measurements. Extracellular water can be measured by the dilution method (bromide space) or by BEI, bone can be assessed directly by calcium neutron activation method or indirectly by DXA and body cell mass can be directly assessed by whole body potassium and nitrogen neutron activation, or indirectly by measuring intracellular water.

Muscle mass can be estimated by creatinine excretion or 3-methyl histidine excretion in the urine.

Choosing the proper method to study body composition depends on availability, the question asked and the ability to interpret the results.

References:

1. Wang ZM, Pierson RN, Heymsfield SB. The five-level model: a new

approach to organizing body-composition research. Am J Clint Nutr

1992:56:19-28

2. Goodpaster BH. Measuring body fat distribution and content in

humans. Curr Opin Clin Nutr Metab Care 2002:5; 481-487.

3 . Mazess RB, Barden HS, Bisek JP, Hanson J. Dual-energy x-ray

absorption for total-body and regional bone mineral and soft tissue

composition. Am J Clin Nutr 1990: 51; 1106-1112.

4. Schoeller DA. Bioelectrical impedance analysis. What does it

measure? Ann NY Acad Sci 2000:904; 159-162.

Laboratory and balance-studies

Rémy Meier,

Aim of the lecture:

To know the benefits and limits of laboratory and balance-studies for nutritional assessments

Learning objectives:

- To be able to identify patients at risk for malnutrition, to use the appropriate laboratory test for

nutritional assessments and to know the strengths and limits of this test.

- To use an appropriate monitoring to assess the response to nutritional intervention.

Content:

A complete nutritional assessment consists of a combination of subjective and objective parameters, but up to now, no single parameter has been shown to be useful in all patients. Most nutritional parameters lack sensitivity and specificity; therefore, methods of identifying malnourished patients are not entirely satisfactory. Laboratory testing is useful for assessment of the nutritional status and monitoring of nutritional interventions. Several laboratory parameters (serum proteins, total lymphocyte counts, vitamins and minerals) are used. Serum proteins have different half-life times. Serum albumin is a good predictor for outcome and reflects disease severity. On the other hand, it is a bad marker to assess nutritional status. Serum albumin can be used for long term control. To assess short term changes, prealbumin or transferrin is more useful. Serum proteins have many limitations. The serum concentrations of visceral proteins decline with overhydration and increase with dehydration independent of nutritional status. Low serum albumin levels exacerbate ascites, lower extremity edema, and gut edema because of depressed colloid oncotic pressure. Serum transferrin is the less affected protein by other factors.

Immune function can be tested by lymphocyte counts and by cutaneous applied skin tests. In most hospitalized patients, delayed hypersensitivity reactivity and total lymphocyte counts are not very useful components of a nutrition assessment profile.

The somatic protein compartment can be evaluated by the creatinine height index (CHI). Creatinine excretion correlates with lean body mass and body weight. The CHI is depended on urine creatinine excretion. Renal insufficiency, meat consumption, physical activity, fever, infections and trauma influence urine creatinine excretion.

Nitrogen balanced studies are often used to assess protein catabolism. In non-stressed conditions, urea composes 30-90% of total urea nitrogen. For usual clinical purposes, nitrogen balance calculation done with urinary urea nitrogen instead of total urinary nitrogen is adequate. It has to be considered that nitrogen excretion calculated from urinary urea nitrogen is affected by increased stress, which can alter urea production and/or increase of non-urea nitrogen by-products. The validity of nitrogen balance is affected by severe nitrogen retention disorders, accuracy of the 24-hour-urine collection and completeness of protein or amino-acid intake data.

A simple assessment to assess catabolic states is also the urea production rate and the urea/creatinine quotient.

Nutritional monitoring and reasons of response can be measured in vivo (by weight gain, N-balance, complication rates) and in vitro measurements by plasma-serum concentration of proteins.

For identifying patients with pre-existing malnutrition or those at most risk, a combination with a comprehensive nutritionally focus physical exam together with carefully selected objective parameters provide the best information.

References:

1. Hopkins B: Assessment of nutritional status. IN Nutrition Support Dietetics Core Curriculum, 2nd ed, Gottschlich MM, Matarese LE, Shronts EP (eds). A.S.P.E.N., Silver Spring, MD, 1993.

2. Teasley-Strausburg K, Cerra FB, Lehmann S, et al: Nutrition/metabolic assessment. IN Handbook for Nutrition Support, Strausburg KT, et al (eds). Harvey Whitney, Cincinnati, 1992.

3. Teasley-Strausburg KM; Anderson JD: Assessment, prevalence and clinical significance of malnutrition. IN Pharmacotherapy: A Pathophysiologic Approach, 2nd ed. DiPiro JT, et al (eds). Appleton & Lange, Norwalk, CT, 1993.

4. Daley BJ, Bistrian BR: Nutritional assessment. IN Nutrition in Critical Care, Zaloga GP (ed). CV Mosby, St. Louis, 1994.

5. Kopple JD: Uses and limitations of the balance technique. JPEN 11(5):173-179, 1987.

6. Konstantinides FN: Nitrogen Balance Studies in Clinical Nutrition. Nutrition in Clinical Practice, 7:231-238, 1992.

7. Twomey P, Ziegler D, Rombeau J. Utility of skin testing in nutritional assessment: A critical review. JPEN 6(1):50-58, 1982.

Food intake assessment

Osman Abbasoglu

Aim of the lecture :

The aim of this session is to introduce various methods for the assessment of food intake and to describe different components of food

Learning objectives :

- To define food intake measurements

- To be able to assess nutritional status in respect to dietary intake

- To classify food contents

Content of the lecture :

Food intake assessment estimates food intakes and is among the main tools for assessing nutritional status. Food intake measurements are used not only for the determination of patient’s nutritional status, but also characterization of the nutritional status of a population for monitoring and surveillance. Assessment of dietary intake has considerable challenge and prone to significant error and bias. Food balance sheets and household budget surveys are indirect methods of food consumption studies Food records and dietary recalls measure food intake on specified period, usually 1-7 days. Because of day to day variability, several days of records may be required to estimate usual food intake. Food frequency questionnaires are developed to describe standardized data on usual long-term diet.

The determination of the consumption of nutrients can be achieved either by analyzing the foods consumed directly or by using food composition tables. Most food composition tables are organized according to the classification of foods into food groups. Dietary reference intakes (DRI) provide standards to serve as a goal for good nutrition.

Suggested readings:

1. Rutishauser IHE, Black AE. Measuring food intake. In: Introduction to Human Nutrition (Gibney MJ, Vorster HH, Kok FJ, Eds.) p.225-249, Blackwell Publishing, 2002

2. Patterson RE, Pietinen P. Assessment of nutritional status in individuals and populations. In: Public Health Nutrition (Gibney MJ, Margetts BM, Kearney JM, Arab L, Eds.) p. 66-82, Blackwell Publishing, 2004

3. West CE, Schonfeldt HC. Food composition. In: Introduction to Human Nutrition (Gibney MJ, Vorster HH, Kok FJ, Eds.) p.249-262, Blackwell Publishing, 2002

Overnutrition

Luboš Sobotka

The aim of lecture:

To explain diagnostic criteria, epidemiology and consequences of obesity and overnutrition

Learning objectives

- To be aware of the prevalence of overnutrition

- To understand the risk of chronic overfeeding

- To recognize the relationship of obesity to metabolic syndrome

- To know the influence of fat accumulation on insulin resistance

Content of the lecture

- Definition of obesity

- The prevalence of obesity

- Complications of obesity and insulin resistance

Overnutrition can be characterized as situation when energy intake is higher then energy expenditure. Chronic overnutrition leads to storage of energy mainly as fat in adipose tissue. Fat is probably also the principal macronutrient high intake of which is responsible for obesity development.

Nowadays obesity is classified according to the BMI. Although obesity is defined as a BMI > 30, the health risks of increased body weight rise progressively when BMI exceeds 25. Morbid obesity (BMI >40) is a serious disease and patients rarely live longer than 60 years. Metabolic risk of obesity can be predicted according to waist circumference. Moderate risk can be supposed if waist circumference is more then 80 cm for men and 94 cm for men. Severe risk if it is more then 88 and 102 cm, respectively.

Overnutrition and obesity are important global health problems that continue to rise in many “developed” countries. The prevalence of obesity had nearly trebled to 21% of women and 17% of men by 1998 in the UK and estimates suggest that over 50% of women and about 66% of men are either overweight or obese. In the majority of European countries the prevalence of obesity increased by between 10 to 40% from the late 1980s to the late 1990s. The frequency of obesity is greater in lower socioeconomic groups, especially after they moved to economically rich country.

Adipose tissue is not only a passive store of energy; it is also an active secretory tissue, producing many hormones, cytokines, and other metabolically active substances that contribute to development of the metabolic syndrome. Especially rezistin, angiotensinogen, PAI-1, proinflammatory cytokines, acylation-stimulating protein, fibrinogen-angiopoetin-related protein and metalothionein are main substances that can play a role in glucose intolerance, oxidative stress and inflammatory reactions, which may contribute to the relationship between obesity and cardiovascular disease. Moreover the release of fatty acids by lipolysis from adipose tissue is increased in obese subjects. This can lead to hyperlidaemia, insulin resistance and toxic damage to the beta cells of the pancreas.

Obesity contributes to the onset of many disabling chronic diseases (e.g. hypertension, coronary heart disease, type 2 diabetes mellitus and some tumors) and to premature mortality. The incidence of peri-operative complications is also higher in the obese, however this has been significantly reduced by laparoscopic surgery. This is mainly due to respiratory failure, impairment in fibrinolysis, hypercoagulable state, and decreased resistance to infections. Therefore prevention and treatment of obesity should be obligatory part of health care.

Nutritional assessments questionnaires and formulas

Yitshal Berner,

Aim:

To have the capacity to choose questionnaire, and the knowledge about the most common questionnaires.

Objectives:

1. To recognize the data components of questionnaire: dietary, habits, and medical history, physical examination and anthropometrics and laboratory data.

2. To recognize what is the purpose of questionnaire: survey, guidelines, special research, decisions making, etc.

3. To know about several running questionnaires.

4. To be able to choose questionnaire for specific purpose.

Content:

Questionnaires are in common use in the medical practice and in nutrition assessment as well as in decisions making process. Every questionnaire has to pass validation to certain “Gold Standard”, and reliability tests.

The data in questionnaire may be of different types: 1. Dietary data, either before analysis or specific components after dietary analysis. 2. Anthropometrics data like height, weight, BMI, or body composition.3 Laboratory results and special tests done. 4. Eating habits like timing of meals and where they are taken. 5. General health questions. 6. Medical data like diagnoses, surgical treatments and drugs.6. Demographic and socio-economic data.

It is very important to evaluate the objective of the questionnaires. Many questionnaires are designed as epidemiological surveys, and others as clinical tools for specific purposes, some are designed for every person and some for specific populations, some are for the detection of malnutrition while other concentrate on risk evaluation due to metabolic diseases as Diabetes, hyperlipidemia and obesity.

Several questionnaires such as the ESPEN guidelines for detection of Hospital Malnutrition (1), the MNA (2) the NSI (3), comprehensive review of the methods is attached (4) and several reprints of important questionnaires are attached o the course program.

The main benefit of questionnaires are the standardization of data collections therefore their use is very important for research mainly of multi-center and international type.

.

Conclusions:

Questionnaires are important tools in the nutritional assessment, but we have to know the purpose, the data and the validation of each questionnaire before using it.

References:

1. Kondrup et al ESPEN Guidelines for Nutrition screening 2002. Clinical Nutrition 22:415,2003.

2. Guigoz Y, et al, Garry PJ. Assessing the nutritional status of the elderly: the mini nutritional assessment as part of the geriatric assessment. Nutr Rev 1996;54:S59-S65.

3. White JV, Ham RJ, Lipschitz DA, Dwyer JT, Wellman NS. Consensus of the Nutrition Screening Initiative: risk factors and indicators of poor nutritional status in older Americans. J Am Diet Assoc 1991; 91: 783-7.

4. Y.N. Berner, Nutritioal Assessment, In E. Lebenthal Nutrition for Longevity.

IASA International Seminars Ltd. Jerusalem 2003. pp 250-266

Energy Balance

Nachum Vaisman

 

Aim of the lecture:

To give a comprehensive overview about the different components of energy metabolism, their relative contribution and the methods to measure them.

 

Learning objectives:

1. To study the components of the energy balance equation.

2. To study the different components of daily energy expenditure

3. To understand the relationship between energy expenditure and body composition.

4. To learn how these methods can be used in clinical situations

 

Summary

Most of the biological organisms tend to maintain their condition, a process called: homeostasis. From an energy point of view, this can be only maintained by conserving energy, or changing one form of energy into another. The nutritional equation reflects the notion that during constant weight the energy intake equals the energy expenditure. This is true when nutrients' absorption is not impaired. Recent studies suggest that there are some situations where these are not kept and a "calorie is not a calorie".

Macronutrients' oxidation yields C02 and water, and during this process

heat and ATP are generated. Measuring O2 consumption or CO2 production can indicate, therefore, what are the energetic needs of the individual and can help us in tailoring his proper diet. Measuring oxygen consumption and CO2 production, as well as nitrogen excretion, can also enable us in defining the contribution of each macronutrient to energy expenditure. Total daily energy expenditure (TEE) consists of 3 main components: resting energy expenditure which consists of 60-70% of TEE, the thermic effect of food ~10% and the rest is expended on activity. In children, extra energy is needed for growth, especially during the first 2 years of life and during adolescence. Resting energy expenditure is the largest component of TEE and the most affected by energy intake and disease states. As resting energy expenditure is mainly produced by lean body mass, the proper way to express REE is by expressing it per kg of LBM rather than by kg of body weight.

Energy expenditure can be studied by few means. When measuring daily oxygen consumption and CO2 production (such as in a room calorimeter) TEE can be calculated. An alternative method for measuring TEE is by the doubly- labeled water method. Field studies suggested that monitoring heart rate can also be used to measure TEE. In practice, the most used method is accomplished by indirect calorimetry, which is used to measure REE and TEF. This is done first thing in the morning in a supine position after 10-12 hours of fasting. The combination of measuring REE and body composition, concomitantly, along with energy intake and absorption, when needed, can help us make the right nutrition support.

 

 References:

 

1.  Lowell BB, Spiegelman BM. Towards a molecular understanding od

adaptive thermogenesis. (2000) Nature:404; 652-660

 

2.          Donahoo WT, Levine JA, Melanson EL. Variability in energy expendiyure and its components. (2004) Curr Opin in Clin Nutr Metab Care 7; 599-605.

3 . Indirect calorimetry and nutritional problems in clinical practice (2001)

Acta Diabetol 38;1-5.

 

4. Ainslie PN, Reilly T, Westertrep KR. Estimating human energy expenditure. (2003). Sports Med 33; 683-698.

Assessment of risk of malnutrition and under nutrition

Luboš Sobotka

The aim of lecture:

To explain the consequences of undernutrition in hospitalized patients in stress and non-stress conditions

Learning objectives:

- To understand the difference between simple and stress starvation

- To know the risks of previous malnutrition for surgical stress and acute illness

- To be educated in functional consequences of malnutrition

Content of the lecture

- Reaction to the non-stress fasting

- Stress reaction and malnutrition

Humans adapt well to starvation, using their reserve stores of carbohydrates, fat and protein, and by reduction of energy expenditure protein conservation. This reaction depends on energy reserves, duration of starvation and any additional stressful influences.

During non-stress conditions subjects with normal body composition can survive more than two months. This leads to marasmic wasting. Glycogen stores are quickly exhausted and glucose is derived from gluconeogenesis from precursor muscle amino acids and adipose tissue glycerol. After period of adaptation glucose production is slowed by a decline in metabolic rate of 10–15% and by reduction of glucose demand. Energy is supplied by an increased (-oxidation of fatty acids and increased production of ketone bodies in the liver. Albumin concentration is unchanged, although plasma half-life proteins may be decreased. Consequences of long-term starvation are: anxiety, depression, impaired muscle function, decrease in cardiac output, hypotension, circulatory failure and reduction of renal function. Malnutrition impairs cell mediated immunity and resistance to infection. Protein depletion decreases respiratory muscle strength and bronchopneumonia is frequent consequence as result of hypoventilation, inability to cough effectively and impaired resistance against infection. The mucosal cells atrophy with impaired absorption of lipids, disaccharides and glucose is also a consequence of prolonged starvation. Starvation predisposes to hypothermia and fever may be absent even with life-threatening infection.

In opposite, the stress starvation occurs when the individual is not only starved but also subjected to the metabolic response to trauma, sepsis and critical illness. In this condition metabolic reaction is mediated by catabolic hormones, insulin resistance, cytokines, eicosanoids, oxygen radicals, and other local mediators. Metabolic rate increases, ketosis is minimal, and protein catabolism accelerates as well as gluconeogenesis with subsequent hyperglycemia and glucose intolerance. Salt and water retention leads to edema formation. This may result in a kwashiorkor-like state with edema and hypoalbuminaemia.

Patients with prior malnutrition who then develop acute illness have less reserve with which to face that illness and do less well, with higher mortality, more complications and prolonged recovery. If surgery is planned in these patients nutritional support improves physiological functions and lessen surgical risk.

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