Mid Term 1 Flashcards
What is screening?
process of identifying characteristics known to be associated with nutritional problems
What is the purpose of screening?
quickly identify individuals with nutrition risks
What is assessment?
process of assessment of body compartments and analysis of structure and function of organ systems and their effects on metabolism
What is the definition of AND on screening?
process of identifying patients, clients of groups who may have nutrition diagnosis and benefit from nutrition assessment and intervention
What are the goals of nutritional assessment?
identify monitor evaluate disease prevention specific deficiencies overall malnutrition
What is morbidity?
the condition of being diseased
malnutrition is associated with increased
morbidity
mortality
hospital length of stay
healthcare costs
Initial nutritional screening includes
pre-existing conditions causing nutrient loss
conditions that increase nutrient requirements
dietary intake
What are the components of assessment?
Anthropometrics Biochemical Clinical Dietary Functional
What are the stages of a nutrient depletion
diet inadequacy
tissue level - needs biopsy
bodily fluid level - urine, blood, etc.
function tissue
enzymatic activity - decreases ex. urea cycle enzymes
functional change - ex. vit A def, not able to see in dark
clinical symptoms - hair loss, dry skin, etc.
anatomical sign
What is anthropometrics composed of
body size
weight
proportions
What is body composition
the proportion of fat, muscle, and bone of an individual’s body, usu. expressed as percentage of body fat and percentage of lean body mass
Anthropometrics allow to assess body size and estimate composition using
height weight circumferences skinfolds ratios
What is the tool used to measure height standing?
stadiometer
What is frankfort plane?
line from eye to middle ear
What is the tool used to measure knee height?
caliper
What are the different ways of measuring height?
standing
knee height
arm span
why is arm span not recommended
not for asians, african americans. spinal deformities
How is frame size measured?
wrist circumference
r = height (cm)/wrist circumference (cm)
not used anymore, it was valid before BMI
What is weight?
sum of all components at each level of body composition - measure of body stores
How is weight measured?
scale
bed scale
chair scale
When should the weight be measured?
in the morning, fasting state, no clothes or shoes
How is BMI calculated?
weight (g)/ height ˆ2 (m)
What is the range of the normal BMI
18.9-24.9
What is the BMI of someone who is overweight
25-29.9
What BMI is considered obese?
more than 30
What is the healthy BMI for elderly
24-29
What are the limitations of BMI measurements?
does not measure body composition
differences in sex, age, ethnicity
limitations in athletes
must be accompanied with other measurements
How is % usual body weight calculated?
current weight/usual body weight x 100
What does it indicate if the %UBW is 85-95%
may indicate MILD malnutrition
What does it indicate if the %UBW is 74-84%
may indicate MODERATE malnutrition
What does it indicate if the %UBW is <74%
may indicate SEVERE malnutrition
How to calculate % weight change?
(UBW-current weight)/UBW x 100
What is considered a significant loss in % weight change?
%2 - 1 week %5 - 1 month %7.5 - 3 months %10 - 6 months %20 - unlimited
Unwanted weight loss can predict:
mortality
surgical outcomes/post op complications
risk of functional assessment
What are the measurements that can be done for body circumference and areas?
Mid-upper arm circ. (MAC) Mid-upper arm muscle circ. (MAMC) Mid-upper arm muscle area (MAMA) Corrected MAMA Mid-upper Arm Fat Area (MAFA) Waist circumference
What is the tool used to measure skinfold thickness?
caliper
skinfold thicknessis an indicative of _____
subcutaneous adipose tissue
Which body areas can we measure the skinfold thickness
triceps
subscapular
biceps
suprailiac
What is the princple behind skinfold thickness
assumes that each site is representative of total body stores
What does MAC indicate?
reflects muscle, bone, subcutaneous fat
– not sensitive to changes in muscle
What does MAMC indicate?
corrects for subcutaneous fat
– not sensitive to changes in muscle
What does MAMA indicate?
reflects muscle and bone
more sensitive to changes in muscle than MAMC
more adequately reflects total body muscle mass
What does cMAMA indicate?
reflects only muscle without bone
not valid in elderly or obese
– not sensitive to changes in muscle
What does MAFA indicate?
reflects the adipose tissue stores
better indicator of total body fat than a single skinfold measurement
What does waist circumference indicate?
reflective of visceral fat stores and abdominal obesity
How is waist circumference measured?
at level of iliac crest/navel
What are the ideal numbers of waist circumference in men and women?
<102cm in men
<88cm in women
What does waist:hip ratio indicate?
estimates distribution of subcutaneous and intraabdominal adipose and muscle tissue
– not used anymore
What are other technological techniques to measure body compositions?
BIA DXA BOD POD Underwater weighing MRI
What is the gold standard in measuring body composition?
MRI
How does Bioelectrical Impedance work?
measures impedance to a low frequency electrical current (mainly from fat)
estimates fat mass, fat free mass, total body water
What are the limitations of BIA?
influenced by hydration status
less precise in atypical bodies (obese)
reference data is limited
How does Dual X-ray Absorptiometry work?
imaging technique, based on attenuation of radiation from different tissue densities
measures bone, soft lean and fat tissues, whole-body and segments
sufficient precision to assess short and long term changes
– recognized as a reference method
What are the limitations of DXA?
expensive
radiation
assumes normal hydration status
How does Air displacement (BOD POD) work?
total body volume measured by air displacement in a chamber
based on fat and lean tissue density
What are the limitations of BOD POD?
access to instruments
residual lung volume must be measured
What is biochemical assessment?
measurement of nutritional markers in blood, urine, etc.
detects subclinical nutrient deficiencies
What are the components that can be assessed by biochemical assessment?
visceral and somatic proteins hematological assessment lipid profile micronutrient assessment immunocompetence assessment
Biochemical assessment can be affected by:
nutritional status
medications
illness
physiological state
What is the ideal level of albumin
40-60g/L or 4.0-6.0g/dL
What is the ideal level of glucose
3.9-6.1 mmol/L
What is the ideal level of iron
11-32 umol/L
Visceral protein status is assessed by the measurement of
serum proteins
RBC
WBC
What is the composition of serum proteins
albumin
fibronectin
transferrin
Transferrin is composed of:
prealbumin
retinol binding protein
In what condition does biochemical assessment has low sensitivity and specificity for nutritional status?
poor protein intake altered metabolism and synthesis hydration inflammation pregnancy madications exercise
What is the half life of albumin
17-21 days
What is the function of albumin
maintain osmotic pressure
transport of large insoluble molecules, drugs, calcium, zinc
What is the function of transferrin
iron transport
What is the function of TTR
transports T3-T4
carrier for RBP
What is the function of RBP
retinol transport from liver to periphery
circulates with TTR
In what condition is albumin high and low?
high during dehydration
low during low protein intake, poor synthesis, overhydration, edema, acute illness, aging
In what condition is Transferrin high and low?
high during Fe deficiency, pregnancy, chronic loss
low during acute illness, chronic infection, PEM, systemic disease
In what condition is TTR high and low?
high during renal disease, Hodgkins disease
low during liver disease, PEM, chronic loss, malabsorption, hyperthyroidism
In what condition is RBP high and low?
high during renal disease
low during vitamin A def., zinc def, hyperthyroidism, liver disease
What are acute phase proteins?
are a class of proteins whose plasma concentrations increase (positive acute-phase proteins) or decrease (negative acute-phase proteins) in response to inflammation.
Give examples of + acute phase proteins
C-reactive protein (CRP)
Ferritin
Give examples of - acute phase proteins
albumin, transferrin, TTR, and RBP
How is somatic protein status assessed?
nitrogen balance
creatinine excretion
immune function
How is positive N balance expressed in terms of anabolism and catabolism?
anabolism>catabolism
How is 0 N balance expressed in terms of anabolism and catabolism?
anabolism=catabolism
How is negative N balance expressed in terms of anabolism and catabolism?
anabolism
How is N balance calculated?
N balance (g/day) = (protein intake g/6.25) - (UUN + 4)
1 mmol of UUN equals to
0.028g of UUN
What are the limitations of N balance
time consuming
prone to errors
missed or incomplete urine collections
does not account for losses due to diarrhea, vomiting, wound leaks
– tend to overestimate
Why is creatinine excretion measured?
excretion is proportional to skeletal muscle
creatinine excretion increases with —-
exercise, meat intake, menstruation, infection, fever, trauma
creatinine excretion decreases with —-
renal failure and age
How is creatinine height index measured?
observed 24h creatinine (mg) excreted/expected 24h creatinine excretion
Hematological assessment is done with
complete blood count
complete blood count includes
erythrocytes (shape, size, color, number) to diagnose anemia
What is anemia?
reduction in the quantity of hemoglobin or in the number of RBC in the blood
leads to decreased oxygen carrying capacity
How are RBC classified in terms of their color?
hypochromic (pale color)
normochromic
hyperchromic (darker color)