ULO 9- Changes in neonatal physiology & adaption to extra-uterine life Flashcards
List 5 methods to reduce heat loss in infants
- skin-to-skin
- warm blankets
- room temperature even
- Wrapping
- dry thoroughly after baths
Describe: Barlow’s test
examines the baby’s hip joints for laxity and the capability for the joint to dislocate with ease
Describe: Moro reflex
is the startle reflex
Explain: 2 cells in the neonate lungs and their function
Alveolar Type 1 pneumocytes- responsible for gas exchange
Alveolar Type 2 pneumocytes- produce surfactant
Explain: Surfactant
is a fluid that reduces surface tension, increases surface area for gas exchange and prevents alveoli from collapsing
What are the normal ranges of a newborns observations
Respiratory rate- 40-60 breaths per minute
FHR- 110-160 bpm
Temp- 36.5-37.5 degrees C
Describe: Acrocyanosis
is when peripheral circulation is immature and the infant has blue hands and feet with a pink body. Is normal and will typically pink up within 24hrs
Define: Thermogenesis
is the process of heat production
- is the bodies mechanism of balancing the body’s heat loss with heat gain
Explain: Hypothermia, Hypoxia and Hypoglycaemia and their relationship to each other
Hypothermia- low body temperature
Hypoxia- low oxygen levels
Hypoglycaemia- low glucose levels
Low oxygen levels lead to a low body temperature which then contributes to low glucose levels
What is the capacity of a newborns stomach
5-7mls (approx 1 Tablespoon)
What are the average newborn assessment measurements?
Heel to crown length: 50-55cm
Head circumference: 35-40cm
Average weight: 3.5-4kg
Explain: 4 ways newborns can lose heat
Evaporation- after being born, having a bath
Conduction- when a baby is put onto a cold surface
Convection- when heat is transferred to the infant
Radiation- baby being put near an open cold window
Adaptive changes at birth- Cardiopulmonary
What factors help stimulate breathing at birth
- pressure of the birth canal and the release of pressure from lungs once expelled
- contractions cause mild asphyxia in the fetus
- mild asphyxia and acidosis induced by cord clamping sensitise medullary chemoreceptors increasing drive to breath
Adaptive changes at birth
What cardiopulmonary changes happen at birth
- A few minutes after cord ceases to pulsate, placental blood flow ceases.
- Ductus venosus and hypogastric arteries close
- The lungs fill with air, and vasodilation of pulmonary circulation occurs
- The foramen ovale and ductus arteriosus close.
Adaptive changes at birth
What happens in the Haematological system
- newborn blood volume 80ml/kg
- haemoglobin high 165-175
Adaptive changes at birth
How can midwives facilitatate cardiopulmonary adaptive changes
- clearing newborn’s airway
- using tactile stimulation
- assessing condition of newborn using Apgar
Newborn Assessment
List all the components you are checking for
Observaions
- Oxygen saturation
- Temperature
- Respiration
- FHR
Palpate: fetal skull bones, fontanelles and sutures
Observe
- posture
- tone, movements
- colour
Assess
- Face: symmetry and movment
- Eyes: shape, clear, dishcharge, lids
- Ears: placement, shape, cartilage
- Nose: placement patency
- Mouth: lips, tongue, gums, palate, reflexes
- Neck: motion, appearance
- Back: spine shape, intact skin
- Chest: size, shape, breast tissue, nipples
- Arms & Hands: motion, symmestry, attitude and creases
- Abdomen: shape, umbilical area, palpability
- Hips: motion
- Legs & Feet: motion, symmetry, atitude, reflex
- Genitalia: gender, complete formation
Adaptive changes at birth
When should a baby have passed meconium
majority pass by 24hrs post birth
ALL by 72hours post birth
What are the 4 reflexes involved in breastfeeding
Rooting
Suckling
Swallowing
Breathing
Explain the 4 reflexes involved in breastfeeding
- Rooting reflex is elicited when the baby’s mouth is touched gently, such as by the nipple. The baby responds by turning the head towards the stimulus and opening the mouth wide
- Suckling reflex is complex. When the baby feels the mouth is full as far back as the hard palate and the back of the tongue, he will use jaws, tongue and cheek muscles to suckle
- Swallowing reflex is well developed in the term infant and the baby swallows about 0.6 ml at each mouthful
- Breathing is coordinated with swallowing by an upper airways reflex to prevent aspiration
How long does it usually take for a newborn to find their way to its mothers breast
45-55minutes
When is surfactant produced from
32 weeks
Transition to extra-uterine life
Describe: Lung fluid
is a clear fluid that facilitates cell proliferation and differentiation.
Transition to extra-uterine life
How is lung fluid removed from the body
- absorbed from the alveoli by osmosis
- expelled through upper airways
- sneeze
What triggers the closing of the foramen ovale
when oxygenated blood returning to the heart via the pulmonary veins increases the pressure within the left atrium
Transition to extra-uterine life- Immunological adaptions
When does colonisation first occur for the neonate
occurs first from the maternal genital tract, then from the mother’s skin, and finally from other people and the general environment
Transition to extra-uterine life- Renal system
What can Urates do
may cause pink or brick-red staining on the napkin. While common and a normal finding in the first few days of life, the presence of urates in the urine of babies more than a few days old may indicate dehydration
Explain: Stepping response
When the baby is supported in a standing position with the soles of the feet on a firm surface, the infant will simulate walking. The presence of this reflex indicates mature extension and flexion mechanisms
