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45 Cards in this Set
- Front
- Back
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Growth Hormone |
Direct effects: diabetic, mobilizes lipid reserves Indirect effect: protein anabolism (increases cell proliferation), promotion of linear growth, gonadic and extra gonadic effects *most GH during puberty *secreted at different rates during the day (pulsatile secretions, can't take blood test) protein/stress/sleep/exercise/glucagon/hypoglycemia -->GHRH + / Somatostatin - --> Anterior pituitary gland --> GHs --> liver + bones --> IGFs (circulation) |
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IGF-1 |
Secretion modulated by hormones, chronic inflammation, nutritional factors, psychological/neurologica factors through GH (marker for GH secretion) |
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Growth Plate Maturation |
Cell differentiation: GH Clonal expansion: IGF-1 Maturation: T3, GH, IGF-1, sex steroid |
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Thyroid hormones |
Allows secretion of GH Contributed to the differentiation and proliferation of chondrocytes Stimulates production of IGF1 and GH Can accelerate fusion of growth plates and prevent replication of osteoblast precursors |
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Epiphysiary growth |
Depends on hormonal factors, mechanical factors (ischemia, infectious process), system equilibrium, systemic equilibrium (inflammation, acidosis and hypoxia) |
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Statis |
Absence of growth |
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Saltation |
Rapid growth |
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Admissibility criteria for WHO growth charts |
- Birth at term - No twins - No smoking - Breastfeeding for first 4 months - Medical visits and immunizations |
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Why Breastfeed? |
- Nutritionally complete (except vitamin C) - Modulates growth and body composition - Anti-microbien factors - Psychological benefits (mother/child attachment) - Benefits mother's health - Breastfed babies are larger but lighter, less malnutrition, more overweight/obese babies |
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Factors influencing growth |
Heredity: 70-90% Influence via: HH axis, thyroid hormones, insulin, sex hormones, Fibroblast Growth Factor (FGF), SHOX Socioeconomic condition: malnutrition, more influence on variability than genetics Nutrition: anorexia, coeliac's, inflammatory disease, abuse (fewer GH receptors, less IGF1) Obesity: less GH, more IGF1and more GH receptors Psychology Chronic illness (HIV, asthma, heart failure) |
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Small sized family |
One or two parents of short stature Normal age for puberty Normal birth weight Healthy child Growth slows at 2-3 years, then normal growth Small height = goal height |
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Small height due to pubertal delay |
Parents have a history of late puberty Normal birth weight, followed by growth deceleration Final height is the goal height |
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Weight delay |
Weight < 3rd percentile for age 0-2 : weight to height ratio < 3rd percentile 2-19: BMI < 3rd percentile Adult: BMI < 18.5 |
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Statural delay |
Height < 3rd percentile |
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Acute malnutrition (wasting) |
– 0-2 ans: ratio poids – taille < 3e percentile (2 écart-type) – 2-19 ans: IMC < 3e percentile (2 écart-type) |
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Chronic malnutrition (stunting) |
- 0-2 ans : longueur <3e percentile pour lâge - 2-19 ans: taille < 3e percentile pour lâge |
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Signs of malnutrition |
Irritability, apathy, muscle decay, decrease in adipose tissue, dry skin, visible ribs, pale, depigmented hair, thin hair |
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Consequences of malnutrition |
stunt in growth, slow growth, poor healing of wounds, vulnerability to infections |
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Overweight |
Risque dembonpoint: 2-5 ans IMC entre 85e et 97e percentile 2-5 ans: IMC entre 97e et 99.9e percentile pou lâge (2-3 écart-type) 5-19 ans: IMC entre 85e percentile et le 97e percentile pour lâge Adultes: IMC entre 25 et 30 kg/m2 |
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Obesity |
IMC 2-5 ans ≥ 99.9e percentile pour lâge (3 écart-type) IMC 5-19 ans ≥ 97e percentile (2 écart-type) Âge adulte: IMC ≥ 30 kg/m2 |
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Final Height / period of growth |
Foetal (30%): nutrition and placenta Infancy (15%): nutrition, health and happiness Childhood (40%): GH, thyroid hormones, good health and happiness Pubertal (15%): GH, testosterone/estrogen
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Genetics of height |
- multiple genes determine height, including SHOX (short homeobox on X chromosome) - heredity of height is between 0.69 and 0.95 in twins - heredity is less important for girls (more variability) - crucial environmental factors |
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Average Dimensions at Birth |
Weight: 7.5 lbs (3.4 kg) Length: 50 cm (19.7") Cranial perimeter = 35 cm * child's head takes up 1/4 of its body, as opposed to 1/10 in adults |
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Changes in Body Composition |
Fat: 14% at birth --> 30% at 6 months --> minimum at age 6 (13% in boys and 16% in girls) --> 18% in adult men and 33% in adult women |
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Gestation |
Pre-term = < 37 weeks At term = 37 weeks Post term = 37-42 weeks 7-6% of babies are born premature 6% weigh less than 2500g |
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Low Birth Weight |
< 2500g |
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Low Birth Weight for Gestational Age |
Weight < 10th percentile for gestational age |
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Macrosomy |
Child born at > 4000 g |
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Pregnancies at risk |
1. Teen mothers or mothers over 40 2. Obese mothers = more C-sections, more twins, more HTA/diabetes 3. Close pregnancies 4. Twin pregnancies 5. Poverty (First Nations, recent immigration) 6. Drugs/smoking |
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Lack of maternal education, low revenue and smoking |
Explain a certain percentage of premature births, low birth weights and still borns |
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Risk factors for prematurity |
- Twin pregnancies (more due to old age and IVF) - C-sections for medical reasons (ex; pre-eclampsia, RCIU, foetal suffering, foetal anomalies) * both of these situations have INCREASED over the past decades < 28 weeks = 0.4 % of all births |
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Ways to determine gestational age |
- Date of amenorrhea - First foetal movement (18-20 weeks) - Height of the uterus - Ballard score from physical exam at birth (appearance + neurological system, ex; skin and tonus) +/- 2 weeks of actual age - Ultrasounds (5-12 weeks): cranio-caudal length (BEST PREDICTOR) - Heartbeat at 16-18 weeks - Ultrasounds (2nd and 3rd trimesters): biparietal diameter, abdominal circumference, length of femur
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Causes for Prematurity |
Foetal: twin pregnancy, foetal distress Placental: placental dysfunction, placental detachment Uterine: abnormal uterus (didelphic), incompetence of cervix Maternal: pre-eclampsia, infections, drugs (ex; cocaine) Other: rupture of membranes, iatrogenic
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Complications of prematurity |
Respiratory system: hyalin membrane illness, pulmonary bronchodisplasia Cardiovascular: persistence of arterial canal GI: hypoglycemia, eating problems, oesophagial reflux, necrosing enterocolitis Neurological: retinopathy, deafness, intra-cranial hemorrhaging Hematology: anemia, vulnerability to infections |
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Long term complications of prematurity (1st year) |
SIDS Asthma Delayed weight gain Gastro-oesophagial reflux Eating problems Hospitalization (ex; bronchiolitis) Growth delay |
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Long term complications of prematurity |
Learning difficulties ADHD Blindness/deafness Cerebral palsy Intellectual deficiency Cardiovascular health Bone health 23 weeks: 25-50% w/ sever handicaps 24 weeks: 35-40% 25 weeks: 3-15% |
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Low Birth Weight Risk Factors |
Mothers with low BMI Low weight gain during pregnancy Mothers with previous RCIU (x2.2) Mothers who had a pregnancy with an RCIU (+20%) Altitude > 2000 m |
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Causes of Low Birth Weight (General) |
Unfavorable uterine environment - circulation and efficiency of placenta - development/growth of foetus - global health/ nutrition of mother |
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Causes of Low Birth Weight |
Foetal: genetics (syndromes, anomalies) = 5-20% TORCHs infections = 5-10% Malformations: 1-2% Twins (3%)
Maternal: pre-eclampsia/HTA (30%), smoking, drug abuse, chronic illness, malnutrition, tx for infertility, close pregnancies
Placental: anomalies (mosaicism, infarctus) = 5% |
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RCIU symmetrical vs. asymmetrical |
Symmetrical: starts early, decrease in number of foetal cells, affects weight, length and cranial circumference equally, due to chromosomal anomalies or congenital infections
Asymmetrical: starts later, affects placental f(x) and O2 supply, affects weight > length > cranial circumference, due to pre-eclampsia, HTA, smoking or malnutrition |
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Complications of RCIU |
Death in utero At birth: asphyxia, hypoglycemia, hypothermia, hyperviscosity of blood, vulnerability to infections, congenital anomalies Long term: slow weight gain, learning difficulties (ADHD), metabolic health (diabetes, HTA, high cholesterol) After 1 year: insulin resistance, diabetes, HTA, high triglycerides |
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Smoking and pregnancy |
Asymmetrical RCIU : < 10 cigs/day = - 170g > 15 cigs/day = -300g Prematurity Nicotine addiction at birth Mechanism: tissular hypoxia (CO, CN), vasospasms, hypoperfusion (due to cathecholamines), decrease in GFs |
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Alcohol and pregnancy |
RCIU (symmetrical) if > 3 drinks/occasion or > 7 drinks/week 1-2/1000 births Facial/cardiac anomalies Growth delay Microencephaly (low IQ) |
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Drugs and pregnancy |
Little medical follow-up Poor maternal nutrition Risk for hepatitis/HIV/syphilis Mortality: chromosomal anomalies, malformations, withdrawal at birth, SIDS RCIU with cocaine = 30%, with heroin = 50%
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Growth Hormone |
Direct effects: mobilizes lipid reserves, causes diabetes Indirect: protein anabolism (cell proliferation), promotion of linear growth |
