birth to childhood Flashcards
labour
-fetus expelled from uterus through vagina
-skin has ‘soft spots’ to allow compression during birth
-control of contractions by positive feedback
false labour
-irregular contractions
-discharge of blood with mucus
true labour
-uterine contractions occur at regular intervals
-occurs in three stages
the three stages of true labour
-stage of dilation
-stage of expulsion
-placental stage
newborns at birth
-highly dependent on mother and greatest risk of death
-birth contractions construct umbilical vessels increasing carbon dioxide in the blood, stimulating respiratory centre in the brain to trigger first breath
-lungs immediately inflate causing major circulatory reconfiguration
-body systems are not fully developed yet
adjustments at birth
-thermoregulatory
-non-shivering thermogenesis
thermoregulatory change
-exposed to a cooler environment
-muscles, nervous system, subcutaneous (under skin) fat are underdeveloped
non-shivering thermogenesis
-highly vascularised, fast oxygen delivery
-special mitochondria produce more heat
APGAR score for newborn
-appearence (skin colour)
-pulse (heart rate)
-grimace (reflexes)
-activity (muscle tone)
-respiration
nervous system development
-most development during infancy (5 weeks to 1 year)
-eyesight lacks colour and depth perception, but keeps developing until ages 8 or 9
-can hear sound, acute sense of taste and smell
-reflexes used to evaluate developing nervous system
types of reflexes
-asymmetric tonic neck reflexes (ATNR)
-step reflex
-grasp reflex
-symmetric tonic neck reflex (STNR)
-moro/ startle reflex
-babinski’s reflex
-rooting reflex
-sucking reflex
asymmetric tonic neck reflex (ATNR)
-from birth to 6 months
-importance for balance and movement
step reflex
-first two months
-not related to walking, which occurs much later
grasp reflex
-from 1 to 6 months
-in response to being touched on the hand
symmetric tonic neck reflex (STNR)
-from two months
-crawl to mother’s breast when placed on abdomen
-not related to crawling which occurs later
moro/ startle reflex
-from 1 to 6 months
-abrupt response to loss of balance
babinski’s reflex
-first two years
-toes fan out when foot is stroked
-if present after two years, indication of damage to nerves connected to spinal cord and brain
rooting reflex
-first 3-4 months
-turns head and open mouth to respond to being stroked
-like searching for mother’s breast
-retention might mean oral motor control issues
sucking reflex
-helps infants hold onto the nipple and swallow milk
development of the nervous system
-formed in the first month of embryonic development
-infections and exposures can have harmful effects on pregnancy
-oxygen deprivation destroys cells
-the last part of the brain to develop is the hypothalamus
premature babies have problems with…
-regulating body temperature because the hypothalamus is not mature prenatally
development of hearing
-the newborn can hear sounds but initial responses are reflexive
-by toddler stage, the child is listening critically and beginning to imitate sounds as language begins to develop
age-related ear problems
-prebycusis
-otosclerosis
prebycusis
type of sensorineural deafness that may result from otosclerosis
otosclerosis
-ear ossicles fuse
development of sight
-special sense organs formed in early embryonic development
-maternal infections during the 5 or 6 weeks of pregnancy can cause visual abnormalities in the developing child
-the infant has poor vision acuity (far sighted) and lacks colour vision and depth perception at birth
-the eye continues to grow until it is mature at the ages of 8 or 9
cardiovascular development
-the heart doubles in size in the first year
-at birth the right ventricle is stronger than the left, this reverses during infancy
-systolic blood pressure increases to meet needs of the growing body
respiratory development
-rapid breathing from abdomen which gradually shifts to using ribs and chest
-lungs do not fully inflate until 2 weeks after birth
-newborn respiration rate-40 to 80 breaths per minute
-number of alveoli increases
-small trachea and close proximity to bronchi increases risk of lung infections
developmental aspects of blood
-the feotal liver and spleen are early sites of blood cell formation
-bone marrow takes over haematopiesis by the seventh month
-incompatibility between maternal and feotal blood by the seventh month
feotal haemoglobin
higher binding affinity to oxygen than haemoglobin produced after birth
how does physiologic jaundice occur
infants when the liver can not get rid of the body of haemoglobin breakdown products fast enough
gastrointestinal development
meconium- first stool 24-48 hours after birth containing amniotic fluid, intestinal secretions, cells and blood
-bowel control achieved in second year
-teething begins at around 6 months- 20 deciduous teeth by age 2, permanent teeth replace deciduous teeth between the ages 6 and 12
development of the lymphatic system and body defences
-lymphatic vessels form by budding off the veins
-the thymus and the spleen are the first lymphoid organs to appear in the embryo
-the immune response develops around time of birth
urinary development
-the kidneys begin to develop in the first few weeks of embryonic life and are excreting urine by the third month of foetal life
-kidneys inefficient up to 6 months, produce dilute urine urine- important to obtain sufficient fluids from breast milk and shouldn’t consume water or diluted formula due to risk hypokalemia
-voluntary bladder control starts at 18 months
development of the skull
-fontanels are fibrous membranes connecting the cranial bones, known as ‘soft spots’
-allows for skull compression at birth
-allow the brain to grow during later pregnancy and infancy
-usually ossify by 2 years of age
-growth of the cranium after birth is related to brain growth
development of the skeleton
-first ‘long bones’ of a foetus are hyaline cartilage
-earliest ‘flat bones’ are feotal skull are fibrous membranes
-as feotal grows, all bones models are converted to bone
-at birth, the head and trunk are proportionately much longer than the lower limbs
-during puberty, female pelvis broadens, and entire male skeleton becomes more robust
development of the skin and body membranes
-lanugo, a downy hair, covers the body the fifth or sixth month of feotal development but disappears by birth
-vernix caseosa, an oily covering, is apparent at birth
-milia, small white spots, are common at birth and disappear by the third week
development of the reproductive system
-gender is determined at fertilisation
-reproductive system structures of males and females are identical during early development
-gonads form on the eighth week
