W7 Physiology of Children (MAH)

Question 1

Growth

Answer 1

• The growth rate of a child varies being highest during fetal life and infancy, slowing down during childhood, accelerating during puberty, and then ultimately ending when adult height has been reached by the end of the adolescent period
• Data is reproducible
• Some differences: gender, gestational age etc

Question 2

Growth charts
What do they show?

Answer 2

• Inc Growth and Inc time, Growth velocity over time
  To provide a brief history of
  i) anthropometry, i.e. growth measurements;
  ii) growth references, the statistical summary of anthropometry, and
  iii) growth charts, the visual representation of growth references for clinical use
• The growth rate of a child varies being
  highest during fetal life and infancy,
  slowing down during childhood,
  accelerating during puberty, and then
  ultimately ending when adult height has
  been reached by the end of the adolescent period
• Data is reproducible
• Some differences: gender, gestational age etc

Question 3

Special cohorts British National Formulary for Children (BNFC)

Answer 3

The terms infant, child and adolescent are used inconsistently in the
literature. However, for reference purposes only, the terms generally used to
describe the paediatric stages of development are:

Preterm neonate= Born at <37 weeks gestation
Term nonate= Born at 37 to 42 weeks gestation
Post-term neonate= Born at >42 weeks gestation
Infant= From 28 days up to 12 years of age
Child= From 2 years up to 12 years of age
Adolescent= From 12 years up to 18 years of age

The terms infant, child and adolescent are used inconsistently in the literature. However, for reference purposes only

Question 4

Key information on the selection, prescribing, dispensing and administration of medicines
used for children

Answer 4

• Guide healthcare professionals on medication use in paediatric patients
• Offers comprehensive information on medication safety in paediatric patients
• Ensures appropriate dosing in paediatric patients
• Supports evidence-based decision making in paediatric medication use
• Supports appropriate and safe medication use in paediatric patients
• Offers guidance on nutrition and growth charts for children

Trials - avoid in children as unethical
Lab < RCT < SR < Meta analysis < NICE Guidelines (evidence-based)

Question 5

Human Growth and Development - StatPearls

Answer 5

1. Infancy neonate- up to 1 year age

Question 6

Onset of GH-dependent growth

Answer 6

1. Prenatal Growth: Even before birth, growth hormone plays a vital role in fetal
   development. It promotes overall growth, particularly in the development of organs
   and tissues. But fetal growth and development is largely under the control of IGFs.
2. Neonatal Period: Although GH levels are high at birth, they don’t significantly
   influence growth during the initial weeks of life. Instead, growth during this period is
   primarily influenced by nutritional status and other hormonal factors.
3. Early Infancy: After birth, growth hormone continues to support growth and
   development. During this period, growth rates are typically high, and infants
   experience rapid weight gain and an increase in linear height. GH helps stimulate bone
   growth, muscle development, and the maturation of various organ systems. During
   infancy, growth is also influenced by other factors like nutrition and thyroid hormone
   levels
4. Childhood Growth: Onset of GH-dependent growth occurs by 6/12 During early
   to mid-childhood, growth hormone remains essential for linear growth. In this
   period, called the childhood growth phase, growth velocity significantly impacts a
   child’s physical development. Height velocity tends to be highest during the first
   two years of life, gradually decreasing as children enter childhood. GH also plays a
   role in bone density development and overall body composition.
5. Pubertal Growth Spurt: One notable period of growth hormone-dependent growth is the pubertal growth spurt. With the onset of puberty, typically around the age of 10-12 in girls and 12-14 in boys, there is an increase in the secretion of growth hormone.
   -This leads to an accelerated growth rate, particularly in linear height, as the long bones of the body experience significant elongation. This phase is critical for achieving adult height.

Question 7

Refer to Endocrinology ISU for

What are the role of these hormones in regulating Physical Growth and Development?

GH
IGF-1/ IGF-2
Insulin
Thyroid hormones
Sex steroids
Leptin

Answer 7

GH- Post-natal growth, liver IGF-1 production, regulates bone growth, impact on height
IGF-1 affects both pre/post natal growth, stimulates a.a. uptake, proliferation, hypertrophy, ossification
IGF-2- regulates pre-natal growth
Insulin- binds to IGF-1 receptor and inc growth velocity
Thyroid hormones- Regulate bone turnover and BMD, promote hypertrophy, differentiation and cell volume expansion
Sex steroids- role in regulating secondary sex characteristics, affect secretion of GH
Leptin- Stimulate chondrogenesis, regulating bone growth

Question 8

Digital growth charts
What is Growth Plate Closure?

Answer 8

Eventually, the growth plates in the bones (epiphyseal plates) close under the
influence of sex steroids, marking the end of linear growth. This typically occurs in late adolescence

Question 9

What are Factors affecting growth rate? (4)

Answer 9

1. Genetics
2. Nutrition
3. Overall health
4. Hormonal balance

Question 10

Cognitive Development
What are some Healthy Habits to Support Physiological Changes

Answer 10

Proper nutrition, regular exercise, and sufficient sleep are needed for healthy physiological development

e.g. Free Breakfast in primary schools delivered by Gov, Healthy weight, healthy wales scheme

Question 11

Wales is failing its children
What does this mean?

(for info)

Answer 11

Report card grades are very low

• Overall physical activity= F
• Physical fitness= C-
• School= B-
• Organised sport and physical activity= C
  etc

This is called “The fourth pandemic of childhood inactivity in Wales”

Question 12

What are the Actions to improve health and wellbeing? (8)

Answer 12

1. Reducing unhealthy eating
2. Increasing physical activity
3. Reducing smoking prevalence
4. Reducing harm from alcohol and drugs
5. Reducing teen pregancy
6. Improving vaccination and immunisatopm uptake
7. Improving mental well-being
8. Reducing accidents amd injuries

Question 13

What are the Physiological considerations when prescribing for Children? (6)

Answer 13

1. Dosage and Formulation
2. Pharmacokinetics and Pharmacodynamics
3. Age-Related Safety Considerations
4. Limited Paediatric-Specific Data
5. Adherence and Compliance
6. Communication and Education

Question 14

Medications that impact on childhood growth and development

Answer 14

• Corticosteroids: They can slow down linear growth and increase the risk of
  developing osteoporosis or thinning of bones.
• Stimulant Medications: associated with modest reductions in height and weight
  during the first years of use; however, the impact on long-term growth remains
  controversial.
• Antiepileptic Drugs: Valproic acid has been associated with an increased risk of
  developmental delays, low IQ, and potential birth defects if taken during pregnancy.
• Antipsychotic Medications: Atypical antipsychotics, such as risperidone or
  quetiapine, may cause weight gain and metabolic changes in children.
• Cancer Chemotherapy: may interfere with normal cell division, resulting in delayed growth and development.
• Systemic Glucocorticoids: can impact growth and development, especially when
  used at high doses or for long periods.
• Isotretinoin: commonly used to treat severe acne and has been associated with
  potential growth plate abnormalities and skeletal changes in some individuals

Question 15

Summary:
Aren’t children just smaller adults?
Can we run clinical trials with children?

What are the ethical considerations? (9)

Answer 15

No! Definitely not!

Inclusion and Diversity
Privacy and Confidentiality
Voluntary Participation
Independent Ethics Review
Beneficence and Non-Maleficence
Justice for all
Autonomy
Post-Trial Access
Informed Consent