growth assessment and monitoring
TRANSCRIPT
Dr. Tauhid Iqbali
MBBS (JIPMER)
MD Pead Jr. II (PMCH Patna)
Learning Objectives To define what is physical growth and to know normal pattern of growth
To understand what is percentiles z-scores and percentage of mean
To know techniques of growth measurement
To define growth monitoring
To know recommendations for interval and parameters for growth monitoring
To know about growth charts
To know what are common growth reference charts
To know how to calculate z-scores and correlation between percentiles and z-scores
Interpretation of growth charts
To know applications of growth charts with examples
GROWTH DEFINITION:
Growth denotes a net increase in the size or mass of tissue
Occurring because of two factors:-
- Multiplication of cells
- Increase of intra cellular substance
NORMAL PATTERN OF GROWTH FROM CONCEPTION TO ADOLESCENCE
FETAL GROWTH(TILL BIRTH ) It is broadly divided into 4 phases: • Up to 16 weeks – slow rate , less than 10 gram/week (100g)
• 16-28 weeks - Accelerated rate , approximately 85 g/week (1005g)
• 28-37 weeks - Maximum rate , nearly 200 g/week (2859g)
• 37-42 weeks - Decelerated rate , approximately 70 g/week (3685g)
BIRTH TO SCHOOL-AGED GROWTH (BIRTH TO 12 YEARS) WEIGHT: Infant looses 7-10% of birth weight in 1st week of life
Birth weight is again achieved by end of 2nd week
Subsequent rate of weight gain is as follows:
AGE WEIGHT GAIN
10days-3months 30g/day
3-6 months 20g/day
6-9 months 15g/day
9-12 months 12g/day
1-3 years 3g/day
4-12 years 2g/day
LENGTH/HEIGHT: Length of term newborn at birth is approximately 50 cm
AGE RATE OF LENGTH/Ht INCREASE
Birth-3 months 3.5 cm/month
3-6 months 2 cm/month
6-9 months 1.5 cm/month
9-12 months 1.3 cm/month
2-5 years 6-8 cm/year
5-12 years 5 cm/year
HEAD CIRCUMFERENCE: Head circumference at birth is 33-35 cm
AGE RATE OF HC INCREASE
0-3 months 2 cm/month
3-6 months 1 cm/month
7-12 months 0.5 cm/month
1-3 years 1 cm/6months
3-5 years 1 cm/year
ADOSESCENT GROWTH(12 YEARS TO 19 YEARS) Peak growth velocity( nearly double the prepubertal GV ) characterized
the commencement of adolescent growth
In girls peak GV start during early puberty ( Tanner stage II-III) with mean
GV of 9cm/yr (range7-11cm/yr)
In boys peak GV begins 2-3 years later than in girls at Tanner stage III-IV
with mean GV of 10.3 cm/yr (range7-13 cm/yr)
The average total growth during pubertal spurt is 27-30 cm
Boys have longer growth spurt period than girls
AGE DEPENDENT Weight Height HC Chest Circumference
AGE INDEPENDENT MUAC BMI Rao’s Index Kanawati’s Index
GROWTH PARAMETERS
TECHNIQUES OF GROWTH MEASUREMENT
Measure to the nearest 10g for infant and 100g for children Allow tared weighing Weighting time should be about half an hour before or after a feed Preferably measure at same time of the day
WEIGHT MEASUREMENT:
LENGTH/HEIGHT MEASUREMENT
Length measurement: For child <2 years of age (or < 87 cm if the age is not available)
Recumbent length is measured by infantometer
Head support Frankfurt plane
Knee straight Sole flat on foot piece Toe pointing upward
If a child is <2 year old but can not lie down then: Length(cm)= Height+ 0.7
Height measurement:
For child >2 years of age(or >=87 cm if the age is not available) and is able to stand
Height is measured by Stadiometer
Measure the height to the last completed 0.1 cm
Heels
Calf muscle
Buttocks
Shoulder blades
Back of head
Frankfurt plane
Head piece firmly on head
Hand on chin
Shoulder level
Hands by side
Left hand on knee: Knee together and leg straight
Right hand on shins: Neels against back And base of board
If a child is >=2 years of age but can not stand then: Height(cm)= Length – 0.7
HEAD CIRCUMFERENCE MEASUREMENT:
Measured upto age of 5 years
Should not be measured before 36 hours of age
Measured to the nearest 0.1cm
Use flexible nonstretchable tape for the measurement
Occipital prominence
Supraorbital ridges
MID-UPPER ARM CIRCUMFERENCE(MUAC): Measured in children between 6 months to 5 years of age
It is an age independent parameter
Measured in left arm
Measured mid-way between tip of left shoulder(acromion process) and tip of elbow
(olecranon process)
Locate tip of shoulder
Locate tip of elbow
Flex elbow
Place tape at tip of shoulder Pull tape past tip Of bent elbow
Mark the midpoint
Arm hanging by side While measuring
If using 3-colour tape: A measurement in-
Green zone - properly nourished
Yellow zone – Moderate acute malnutrition
Red zone – Severe acute malnutrition
GROWTH MONITORING
Definition: Following the growth rate of a child in comparison to a standard by frequent periodic anthropometric measurements in order to assess growth adequacy
The purpose is to determine whether
a child is growing “normally” or growing “ abnormally” i.e. Has a growth problem
Purpose of growth monitoring:
Growth Monitoring involves five steps
Step 1: Determining correct age of the child
Step 2: Accurate weighing of the child
Step 3: Plotting the weight accurately on a growth chart of appropriate gender
Step 4: Interpreting the direction of the growth curve and recognising if the child
is growing properly
Step 5: Discussing the child’s growth and follow-up action needed with the mother
STEPS IN GROWTH MONITORING
RECOMMENDATIONS FOR INTERVAL AND PARAMETERS FOR GROWTH MONITORING
Age group Parameters Intervals
Birth -18 months Weight, Length Head circumference
Birth, 6wks,10wks,14wks, 9 Mo,15 Mo and 18Mo
18 months -5 yrs Weight, Height 6 monthly
>5 years Weight, Height , BMI Annually
GROWTH CHARTS
The most powerful tool for growth monitoring
Growth charts are visible display of child’s physical growth and development
It was first designed by David Morley and was later modified by WHO
Blue charts for boys and pink charts for girls
COMMON GROWTH REFERENCE CHARTS
• NCHS 1977(National Center for Health Statistics) • WHO 2006 • CDC 2000(Center for Disease Control and Prevention) • Indian reference charts Agarwal DK et al Khadilkar VV et al Marwaha RK et al
WHO CHARTS Available for age group of birth to 19 years Standards for age 0-60 months were developed from data collected in WHO- MGRS
(Multicenter Growth Reference Study) which represent the best physiological growth standards from birth to 5 years of age in breastfed infants Standards for age 5 years to 19 years were developed from original NCHS 1977 data Disadvantage of WHO growth charts Few children aged 0-60 months are diagnosed underweight even if they are not
CDC 2000 CHARTS Available for age group of birth – 20 years These are revised version of original NCHS 1977 data Sample population were formula/mixed fed children Disadvantage of CDC growth charts Do not truly reflect ideal growth of breastfed children
WHICH GROWTH CHART TO USE?
RECOMMENDATIONS:
Under 5 children - WHO 2006 STANDARDS
Above 5 children - Nationally representative references
Recommendation for indian children:
INTERPRETATION OF GROWTH CHARTS AND GROWTH PARAMETERS
PERCENTILES
Percentiles are obtained by dividing an ordered set of data into 100 equal sized group If a 3-month-old child is in the 40th percentile for weight that means 40 percent of 3-month-old boys weigh the same as or less than this baby and 60 percent weigh more
50th percentile means 50 per cent above or under
Z-scores or SD scores
It is used to describe mathematically how far a measurement is from the median (average)
50% 50%
97%
Correlation between percentiles and z-scores
Z-score Exact percentile
Rounded percentile
0 50 50
-1 15.9 15
-2 2.3 3
-3 0.1 1
1 84.1 85
2 97.7 97
3 99.9 99
How to calculate Z scores (Standard Deviation Score)
Example: Actual length 96.1 cm Median 90.4 cm Standard deviation 3.3 Z score = ( 96.1-90.4)/3.3 = 5.7/3.3 = +1.73
97%
PERCENTAGE OF MEDIAN
This is merely the weight/height of the individual child relative to the average weight/height of the comparable children in the reference population, expressed as a percentage For example: A 80 cm tall girl weigh 8.0 kg and the average weight for 80 cm tall girls is 10.2 kg Therefore, the percent of median for this 8.0 kg girl is 78.4 %
For height <90% - Short stature
For weight <80% - Underweight
Under weight
Growth chart types
Percentile graphs have a narrower range, because the 97th centile corresponds approximately to a Z score +2 Hence a Z-score of +3 or -3 is more likely to be definitely abnormal (above 97 centile or below 3 centile)
Percentile chart Z-score chart
INTERPRETATION OF GROWTH CURVE
This is determining whether the child is growing appropriately or not.
Normal growth curve: a healthy child’s growth curve is parallel to the printed curves on the chart.
• The direction of the growth curve is more important than the position of the curve on the chart
Important consideration on premature infants where growth failure can be over diagnosed, this can be avoided by subtracting the weeks of prematurity from postnatal age when plotting the growth measurements
A horizontal growth curve (static) :
• This indicates danger, this means the child is not growing.
• A sign of disease, especially malnutrition.
• This makes them prone to recurrent infection as they can not resist disease
Downward growth curve:
• Indicates a very dangerous situation where the child is losing the weight.
• This requires extra care immediately
An upward curve in the growth chart is ideal
A flat and downward curves are not desirable
INTERPERATION OF GROWTH PARAMETERS
May be abnormal
Use BMI
EXAMPLES AND APPLICATIONS
CALCULATING AND PLOTTING MPH
MPH is plotted on growth chart at 18 years of age Normal range is 2SD above or below the MPH (Which approximately corresponds to +/- 8cm
For example: Father Ht - 164cm
Mother Ht - 151cm
Assessment
MPH-151(143-159cm)
CALCULATING AND PLOTTING GROWTH VELOCITY
For example: 12 year old girl Ht – 135 cm
After 6 months Ht – 138.5 cm
A = 3.5
B = 6
GV=3.5 X 12/6 =7 cm Per year
Point -12.25 years
Assessment GV – 50 Percentile
GV = A x 12/B Per year A- Interval growth B- Months b/t measurements
12 year old girl
Ht - 135cm,Wt - 28kg
Father Ht - 164cm
Mother Ht - 151cm
Assessment: MPH-151(143-159cm)
Ht age-9.5years Wt age-8.5 years
Familial short stature
Follow-up 6 months
Ht – 138.5 cm
GV=3.5 X 12/6 =7 cm Per year
Assessment GV – 50 Percentile
13 year old boy
Ht – 135cm,Wt – 30kg
Father Ht-169 Mother Ht-156
Bone age – 10.5 years
Assessment MPH - 169 cm
Height age -9.5 years Weight age -9.5 years
Constitutional short stature
10 year old girl
Ht-120cm Wt-15kg
Father Ht-163cm
Mother Ht-150cm
Interpretation Height age-7years
Weight age-4 years
Nutritional short stature
8 year old boy
Ht-100cm Wt-18kg
Father Ht-169cm
Mother Ht-156cm
Bone age-3 years
Interpretation Ht age - 3.5cm Wt age - 5 cm
Endocrine-GHD/Hypothyroidism
12 year old boy, obese
Ht-160cm Wt-70kg
Father Ht-169cm
Mother Ht-156cm
Interpretation Ht age-13.5years Wt age-19 years
Constitutional obesity
12 year boy, Obese
Ht-132cm Wt-59kg
Father Ht-169cm
Mother Ht-156cm
Interpretation Ht age – 9years
Wt age - 15.5years
Pathological obesity
SHORT STATURE
Wt age << Ht age < Age – Nutritional
Ht age << Wt age < Age - Endocrine
OBESITY
Age < Ht age < Wt age – Nutritional
Ht age < Age < Wt age - Endocrine