Examination of nutritional status (pathobiochemistry)

Calculations

 * Quetelet index = BMI (body mass index) = weight in kg / (height in m) 2
 * Calculation according to Harris and Benedict equations - energy expenditure at rest (REE) in kcal / day
 * for women = 655 + 9.6 × (weight in kg) + 1.7 × (height in cm) - 4.7 × (age in years)
 * for men = 66 + 13.7 × (weight in kg) + 5.0 × (height in cm) - 6.8 × (age in years)
 * factors influencing resting energy expenditure:
 * Stress factors:
 * fasting: 0.85
 * surgery: 1.0–1.2
 * sepsis: 1.4–1.8
 * Fever: 1.0 + 0.13 per degree Celsius
 * peritonitis: 1.2–1.5
 * cancer: 1.1 - 1.45
 * Physical Activity Factors:
 * patient all day in bed - 1.15
 * patient lying on the toilet - 1.20
 * patient walking around the room - 1.25
 * patient walking after ward - 1.30
 * Calculation of total energy expenditure = REE × stress × activity

Anthropometric tests

 * weight loss - refers to total body weight
 * measurement of skin lashes over:
 * triceps
 * shovel
 * pelvic christ - refers to the evaluation of total fat
 * measurement of the circumference around the middle part of the arm - refers to body weight without fat

Laboratory tests

 * Biochemical
 * albumin (does not fall below 35 g / l)
 * prealbumin (does not fall below 0.10 g / l)
 * transferrin (should not be below 1.7 g / l)
 * IGF binding protein 3
 * fibronectin
 * S-Fe, Cu, Zn
 * S-urea, dU-urea
 * glucose
 * Hematological
 * hemoglobin, hematocrit, number erythrocyte, number leukocyte, number lymphocyte, number platelet
 * Immunological
 * humoral immunity (IgG, IgA, IgM)
 * cellular immunity (delayed hypersensitivity skin tests)

Calorimetry
The most objective determination of energy expenditure is examination using indirect calorimetry. However, this is not a commonly used technique. Far more is the estimate of energy expenditure by calculation based on empirical equations (see above). The device enables non-invasive monitoring of respiratory gas exchange with continuous expression of the value of oxygen consumed and carbon dioxide produced in time intervals of 1 minute.

Nitrogen balance
There is a dynamic balance between the production (anabolism) and degradation (catabolism) of tissue proteins. In healthy individuals on a balanced diet, nitrogen intake and output are in balance. Under pathological situations leading to damage to the body, after surgical procedures or during prolonged stress, a metabolic response occurs in which catabolism predominates over anabolism. A negative nitrogen balance is created. The simplest approximate calculation is obtained by comparing the N-supply contained in proteins with the N-content of urea excreted in 24 hours in the urine (dU-urea): Note: The body is not able to store proteins in stock, as is the case with glycogen for carbohydrates or triacylglycerols for fats. There is only a so-called amino acid pool, which is about 70-80 g in an adult, which is depleted in a few hours during starvation. ''
 * N-equilibrium (in g) = (protein supply / 6,25) - (dU-urea in g) + 2,5
 * Protein balance = protein intake - protein loss (= (dU-urea in g + 4) x 6.25)

The recommended minimum intake protein per day for a 70 kg individual is 1 g / kg body weight, which corresponds to 11 g N per 24 h.

Related Articles

 * Nutritional Assessment
 * Eating Disorders

Source

 * ws:Vyšetření stavu výživy (patobiochemie)