Nutrition Assessment: Biochemical, Physical and Anthropometric Assessments & Energy, Fluid and Protein Requirements Flashcards
Electrolytes of significance
- sodium Na
- Potassium K
- Chloride Cl
- Calcium Ca
- Magnesium Mg
characteristics of Na
- The most abundant cation in the ECF
- A major regulating factor for bodily water balance
- Altered values are likely related to hydration status, e.g dehydration with ↑ [Na], versus total body status
characteristics of Cl
passively follows sodium and water
characteristics of K
- The primary cation in the ICF (inside cells)
- A major regulating factor for muscle and nerve excitability, fluid balance (like Na), protein synthesis, enzymatic reactions, and carbohydrate metabolism
- ↓[K] common in patients with nausea, vomiting, or diarrhea (hypokalemia)
- Closely monitored in patients with high re-feeding risk
K ranges
- too little <3 mmol/L
- 3.5-5.2 mmol/L
- too much >6 mmol/L and needs treatment
What electrolyte is best for total body status?
potassium
* can see if losing a lot more fluid (such as through diarrhea)
Single Nutrient Serum Levels
Nearly all vitamins and minerals can be measured in serum
* May ↑ or ↓ with certain diseases / conditions – may or may not be valid to measure
* ? If serum levels reflect body stores – best measure we have
Lipid Panel / Lipid Profile
A group o ftests that are often ordered together to determine risk of coronary heart disease and includes:
* Total cholesterol
* Low Density Lipoprotein (LDL or bad cholesterol)
* High Density Lipoprotein (HDL or good cholesterol)
* Triglycerides (TG)
dyslipidemia
A condition marked by abnormal concentrations of lipids or lipoproteins in the blood
Fat soluble vitamins
A,D,E,K
malabsorption of fat-soluble vitamins
- in disease that interferes with fat absorption (such as Crohn’s disease and cystic fibrosis)
- in individuals who have had gastric bypass surgery
- short gut surgery
common tests for fat soluble vitamins
A
* serum retinol (not the best)
* serum carotene
D
* D: 25(OH)D → good marker of total body except renal disease and liver disease)
* 1, 25(OH)2D → active form, but not good marker
E:
* α-tocopherol
* α-tocopherol:Cholesterol ratio
K:
* International Normalized Ratio (INR) → delayed prothrombin time; K is needed for hydroxylation of the coagulation cascade
* Protein Induced Vitamin K Absence (PIVKA) Integrated → how much you ate
Nutrient Deficiency in Nutrition Assessment
Features of a physical assessment
examine for clinical signs and symptoms reflecting malnutrition
* physical signs do not usually appear until deficiency level is severe
* physical signs are often non specific
Where might there be concern for micronutrients?
more specific lab tests should be done
* alcoholism
* dietary assessment shows high risk
* liver failure
* renal failure
* high GI losses
What does physical assessment generally examine for?
- protein deficiences
- energy deficiences - lack of weight gain, lack of protein
what to look for with protein and energy deficiency
Result of ↑ nutrient demands, ↓ intake
* hair - dry, dull, alopecia, very brittle and falling out
* face - drawn in, temporal can feel severe indent
* skin - delayed wound healing, slin breakdown and/or decubitus ulcers
* musculoskeletal - wasting, ↓ strength, sunken clavicle
* Edema - fluid overload
Edema
- may be sign of protein deficiency
- may be a sign of very low activity level → lower body especially if not raising feet
- may indicate poor renal function (chronic or acute)
- can contribute to skin breakdown →gets stretched and see shiny skin
What is best treatment for peripheral edema?
tensor stockings to push blood volume back up
* elderly sometimes given medication but doesnt typically work
Ascites
The liver stops making albumin which is the main protein to draw fluid from tissue and so fluid collects within spaces in the abdomen. The tummy gets hard and makes an echo sound
* So if someone has problem of big belly maybe liver problem
* Babies can get so big and push up to lungs and make hard to breath
* Can develop at varying degrees; in babies in 8-12 weeks sometimes with malnutrition, can take over a year with adults with malnutrition; very serious if developers within a few days such as in short gut sometimes
What is included on the SGA?
- weight/ weight change
- dietary intake - subjective so ask about recent intake, changes and types
- gastrointestinal symptoms - many associated with malnutrition
- functional capacity - activities of daily living
- disease state/ comorbidities as related to nutritional needs - any symptoms
- physical exam
anthropometry
Used to determine body size and proportions → height, weight, circumferences
* Some pt cannot stand to be measured → too ill, wheelchair bound, unable to straighten
* If measuring supine should be lying flat/straight, take measurements on both sides
Most important anthro measurement
Body weight → drug therapy often relies on this
* Standing, chair, bed scales available
* take amputations into account (tables available with percentage that limbs typically represent)
* fluid status → edema can affect weight, attempt to determine “dry” weight
How often should weight be taken
Needs to be measured on an ongoing basis → attempt at least weekly measurements
Evaluation of body weight
weight alone gives little information, need to compare measurements to reference values
* Body Mass Index (BMI)
* Ideal Body Weight (IBW)
* % of IBW
* Usual Body Weight (UBW) – % of UBW
BMI pros and cons
pros
* easy to use
* correlates with body fat measures
* not influenced by height
* high correlation with specific diseases
* permits comparison between groups
cons
* not as useful for children, elderly, athletes, pregnancy and lactation
* doesn’t take body comp into consideration → hydration status, fat distribution, muscle mass
BMI
Evaluates weight
* nomogram
* calculation = weight (kg)/height (m)2
Interpretations of BMI
- different values at age 65
- evaluation of obesity
- association with health risks → high blood pressure, CVD, Type 2 diabetes
IBW
m2 x ideal BMI calculation → healthy weight range is broad
* Age 19 - 65 year: BMI 20-25
* Age ≥ 65 year: BMI 22-29 (controversial cut-off; many suggest 27). In this course we will use 27.
* In clinical populations may have slightly different ranges
18.5-24.9 used in healthy population
% IBW
interpretation of %IBW
in men and non-pregnant females
MEMORIZE
UBW
Usual Body Weight → used to determine weight changes
* UBW may not be healthy (low or high) but it is used for assessing unintentional weight loss (or gain)
* used for some differential diagnoses
* can be a nutrition screening tool
% UBW = ??
% weight change = ??
most important weight assessments
- %UBW (informative of risk but percentage change with time is even more important)
- %weight change (most informative in terms of relative nutritional risk)
Interpretation of %UBW
In Adult Males & Non-pregnant Females
Interpretation of % Weight Change
In Adult Males & Non- pregnant Females
can also look at gain
When is extreme weight loss apparent do to fluid loss?
10% in a week would be all fluid loss, it takes much longer for weight loss with starvation. Unsafe to lose this much even with fluid because renal mechanisms try to keep it in check.
What does sudden weight gain indicate?
Wt gain of more than 1-2kg/week likely indicates change in fluid status
* check other indicators of fluid status
* edema
What are body circumference/ area measurements used for?
Used to estimate skeletal muscle mass (somatic protein stores) & body fat stores
Waist circumference
- correlates with visceral fat stores
- useful index of abdominal obesity, metabolic syndrome
- risk for CVD and Type 2 diabetes in overweight/obese individuals
What waist circumference is risk for CVD/ T2D
- males > 40” or 102cm
- females > 35” or 88cm
How is waist circumference measured?
Measured at the part of the trunk located midway between the lower costal margin (bottom of lower rib) and the iliac crest (top of pelvic bone) while the person is standing, with feet about 25- 30 cm apart (10-12 in) Measured to the nearest 0.5 cm (1/4 in), at the end of a normal expiration.
Waist-to-hip ratio
estimates distribution of subcutaneous and intra- abdominal adipose and muscle tissue
What waist-to-hip ratios are considered increased risk for morbidity and mortality
> 1.0 in men
0.8 in women
Skinfold thickness
Measurement of subcutaneous adipose tissue stores
* Measured with calipers
* Adipose stores vary with age, sex, race
* Using multiple sites is more representative than only one site
* Need to be done by trained individuals
* Measured in triplicate
What are the 4 most common measurements for skinfolds?
- Triceps skinfold (TSF)
- Subscapular skinfold
- Biceps skinfold
- Suprailiac skinfold
What are triceps skinfold measurements important for?
measurement of subcutaneous fat
* <5th percentile is fat energy depletion
What is mid arm circumference measurements important for?
muscle - energy and protein depletion
NHANES I and II and Nutrition Canada Reference Tables (for nutrition status)
Risk for altered nutritional status
* >95th percentile
* <5th percentile (fat energy depletion; muscle energy and protein depletion)
Risk for depleted nutritional status
* 5th-15th percentile
Importance of skinfold measurements in peadiatrics
Really important in peadiadrtcis for measuring failure to thrive. When skin flab is less than 5% means using up fat stores to meet energy needs. A lot of cardiac baby have very little tricep
What are PES statements
structured sentence that describes the specific nutrition problem that you (the dietitian) is responsible for treating and working toward resolving, the cause/s of the problem and the evidence that this problem exists.
PES components
- The Problem (P) – the Nutrition Diagnosis
- The Etiology (E) – the cause/s of the nutrition problem (Nutrition Diagnosis)… secondary to…
- The Signs and Symptoms (S) – the evidence that the nutrition problem (Nutrition Diagnosis) exists… as evidenced by…
nutrition assessment of hospitalized patients
- a) Medical and Social history
- b) Dietary history
- c) Biochemical data
- d) Physical examination
- e) Anthropometry and body composition
- f) Estimation of energy, protein and fluid requirements (uses some of above information)
What is used to estimate of energy, protein and fluid requirements
Measure BMR/REE
Factors to consider in energy assessment
- Age (BMR goes down with age)
- Gender (males tend to have higher metabolic rate)
- Height/Weight
- Body Comp
- Nutritional Status (metabolism downregulates with undernutrition)
- Activity
- Illness (presence and severity)
- Ventilation (REE goes down because does work for you)
- Malabsorption
- Trauma
- Wounds
- Medications
- Infection & Fever
What equation does AHS use to determine BEE?
Mifflin St Jeor
* may over-estimate BEE
* Emerging as most commonly used equation in healthcare – height, weight, gender specific
* wt in kilograms (kg), ht in centimetres (cm), age in years (yr) (RMR) kcal/day:
What other measurements are considered with BEE when determining energ needs?
Activity factors
* physical activity from bed-bound to strenuous activity
* may change over time
Stress factors
* stress from various clinical states
* may change over clinical course
What are the Activity Factors?
MEMORIZE
- 0.95 sleep
- 1.0 Bed-rest
- 1.2 Out of bed plus very light activity
- 1.3-1.5 Sedentary
- 1.7 Normal Activity
most inpatients are 1.0-1.2
Why is AF normal activity not “normal”?
It is more the ideal normal activity (doing about 10,000 steps a day at a brisk pace) and this is not the norm for our society
* essentially heart rate should be going up with longer duration
Who are stress factors meant for?
Meant for hyper metabolism - consider diseases associated with this
* cancer is about 20% more, colon cancer not usually, but lung, bone, liver are and probably stress factors of 1.2.
What are the stress factor measurements?
- 1.0-1.2 in hospital, could be higher if have infections
- 1.0-1.3 in cancer patients, but can have wide range and even higher; typically most cancer pts: 1.2-1.3
What is the difference between BMR and REE
only about 2%
which weight measurement is the best to use for energy assessment?
If body weight less than 90% of IBW or more than 120% of IBW, use IBW; other wise if the actual body weight of the patient is between 90-120% ideal body weight use the actual weight of the patient. Use actual body weight if no fluid retention
IBW range
* Age 19 - 65 year: BMI 20-25
* Age ≥ 65 year: BMI 22-27
How is activity factor measured
- determine hours spent in each AF category for a total 24 hr day
- times the AF by number of hours and add them up
- Add total and divide by 24
How is TEE measured?
BEE x AF x SF
How are kilocalories used to determine total energy requirement?
not for BMR
- 25 - 35 kcal/kg (rough estimate) → Increases or decreases with trauma, burns or coma etc.
- 21 kcal/kg for obese pts (not reccomended to use this methof for obese patients however)
What is reccomended to measure energy needs in obese patients?
ASPEN guidelines recommend using indirect calorimetry to measure energy needs in an hospitalized obese patient with chronic disease as energy requirements may vary widly. When not available consider use of Penn State/Mifflin St Jeor
Pros of indirect colorimetry
- accurate measurement of caloric req’s
- information on substrate utilization
- can see acute changes
- can be used with ventilated patients
Cons of indirect colorimetry
- expensive
- trained personnel
- precise testing criteria must be followed which is unlikely in hospital setting → usually 10-20% higher in inpatients since it cannot be done in the fasted state (it will be post-prandial)
Protein requirements
Healthy Adults
- RDA 0.8 g/kg body weight/day
In hospital
- minimum requirement = 1g/kg body weight/day - 1.2-1.9 g/kg/d (burns even more).
- kids higher
Based on ideal weight if bodyweight outside the normal physiological range.
Conditions that may change protein requirements
Need to monitor the body to tolerate it and prioritize what is most important.
* renal disease (dialysis)
* liver disease (normally 1.2-1.5 but with end stage 0.8 to avoid ammonia production)
* Burns
* Critically Ill patients in ICUs
* Many other clinical populations
What is the the total body water composition and minimum required to survive?
- 55-65% of body weight
- 35 mL/kg is what you need to survive (18-65) which most people exceed
where does hydration status affect other areas of nutrition assessment?
need to look at all inputs/ outputs
* biochemical measurements (urine colour throughout the day)
* physical exam (eyeballs sunken and/ or dry)
* anthropometrics (fluid retention)
fluid requirements (hydration)
Should base on best estimate of weight and/or dry weight.
* use actual weight
* Not IBW (usually used for energy)
MEMORIZE age and weight category
Fluid inputs
- food and drink
- IV fluids
- irrigation
- oxidative metabolism
fluid outputs
- urine and stool
- insensible losses
- sweating/fever
- wound output
- vomiting
- diarrhea
- medications – diuretic
