Infant Development and Feeding: Embryology, Reflexes, and Pathologies

At what week is the embryo referred to as a fetus?

The 8th week of gestation

When do the structures required for feeding begin to form?

From week 3 to 5 of gestation

When is most anatomical development completed?

All basic structures by week 12, but completed by week 20.

In Utero, what do the structures required for feeding form from?

Branchial arches

What is the significance of the epiglottis in infants?

It makes contact with the soft palate when supine, which helps them be 'obligate nasal breathers'

What is different in paediatric anatomy?

Tongue is bigger in proportion, epiglottis, hyoid and glottis more compressed.

What changes occur in the respiratory system by week 32-34?

Surfactant appears, making the lungs functional for breathing.

What is the primary function of the brainstem at birth?

It controls life-sustaining reflexes such as breathing and suckling.

Neurological system at birth

Cerebral cortex is very primitive with neurons poorly connected. Brainstem is the most highly developed area.

What is anencephaly?

A condition where the baby is born without parts of the brain and skull due to failure of the neural tube to close in early pregnancy.

What are the stages of feeding in infants?

Oral prep, Oral, Pharyngeal, and Oesophageal stages.

What is different about all stages of feeding in neonates and young children?

All involuntary

What reflex causes an infant to turn their head towards stimulation on the lips or cheek?

Rooting reflex, which emerges in the 3rd trimester.

What stimulates tongue protrusion reflex?

Tactile touch to anterior part of tongue.

What stimulates tongue lateralisation reflex?

Tactile touch to lateral surface of tongue.

What stimulates phasic bite reflex?

Tactile touch to gums.

What stimulates gag reflex?

Stimulation to posterior 2/3rds of tongue and pharyngeal wall. Moves back to posterior 1/4th of tongue after 9mths.

What stimulates a cough reflex?

Detection of material in entrance to laryngeal vestibule.

What stimulates a swallow reflex?

Material in the posterior oral cavity.

What is the difference between nutritive suckling (NS) and non-nutritive suckling (NNS)?

NS is associated with feeding, while NNS is associated with comfort and regulation.

What is the difference between suckling and sucking?

When it becomes under voluntary control (at around 2-4 months), it's called sucking.

Where is the nipple compressed during feeding?

Against hard palate.

What is the significance of intraoral pressure during suckling?

It helps withdraw milk from the breast during breastfeeding.

How do infants tongues move when breastfeeding?

Wave-like movement

How to tell if it's a gag or choke?

Gag is noisy and red faced, choke is quite and blue faced

What are some protective feeding reflexes?

Tongue protrusion, tongue lateralisation, phasic bite, gag, cough.

What happens to the fluid in the lungs at birth?

It is squished out and any remaining fluid is absorbed by the body.

What is the role of the pons and medulla in the brain?

They are part of the brainstem and are involved in controlling basic life functions.

When does the suckling reflex transition to voluntary sucking?

Around 2-4 months of age.

What is the typical development timeline for the respiratory system in utero?

Development begins at week 4, with visible lung structures by week 8 and functional breathing by week 32-34.

What is the significance of the large buccal fat pads in infants?

They help with the sucking mechanism and reduce space in the oral cavity.

What is the typical development of the neurological system in utero?

All neurons are formed before full term, but many synaptic connections develop after birth.

At what gestational age can full-term babies usually feed orally?

Around 34 weeks, sometimes earlier.

What triggers the swallow reflex in infants?

The accumulation of bolus volume in the valleculae.

What happens to the soft palate during swallowing?

It elevates.

What movements occur in the larynx during swallowing?

The vocal cords come together, the trachea closes, and the trachea and hyoid bone move up and forward.

What is the significance of the epiglottis in infants during swallowing?

It may tilt over larynx, or may not (but as trachea closes the don't aspirate)

What is the normal breathing pattern for infants during suck-swallow-breathe?

40 - 65 breaths per minute, stopping breathing for approximately ½ second during a swallow.

What is the typical suck-swallow-breathe ratio in infants?

1:1:1 initially, but as they mature- more sucks per swallow (3:1)

What are the current WHO recommendations for breastfeeding?

Feed within the first hour of life, on demand, and exclusively for the first 6 months.

When can complementary feeding begin for full-term infants in western countries?

Around 4 months.

How is milk expelled from a bottle?

Compression, or negative pressure

What is a common feeding-related pathology in infants?

Choking and aspiration pneumonia.

What feeding challenges might premature infants face?

Feeding needs related to interruption of typical feeding development and possibility of associated condition (eg. cerebral palsy).

What is the role of taste preferences in infants?

Fetuses can detect taste at around 15 weeks, and exposure to flavors during pregnancy shapes preferences.

What are some feeding pathologies in infants and children that SLTs can support with.

Choking, aspiration pneumonia, feeding inefficacy, transition from tube to oral feeding, significant feeding aversion, premature infant feeding, cleft lip + palate, neurological issues, and tracheosophageal fistulas/atresia.

What is the difference between Oesophageal Atresia and Tracheosophageal fistula?

Oesophageal Atresia - where the oesophagus does not continue as one tube.

Tracheosophageal fistula- abnormal connection between oesophagus and trachea.

How can an SLT support a premature baby?

Reduced stimulation on ward, communication with mother, cue based feeding, assessment and intervention.

What is a neophobic response in infants?

A normal rejection of food that starts around 12-18 months, where rejection of food is based on it looking 'poisonous' (green, or not looking as it should)

What are some features of bottle feeding?

Different flows of bottle teats, potential for overfeeding, and the choice between formula or expressed breast milk.

What is the significance of vitamin D in infant nutrition?

It is essential for growth and development.

What are some signs that an infant may be ready for weaning?

Developmental cues including, and beyond, postural stability.

What is the impact of cleft lip on feeding?

It affects the ability to form a seal around the teat and create intraoral pressure.

How does cerebral palsy affect feeding in infants?

Difficulties with tone, coordination, and retained reflexes.

What is the importance of tracking centiles in growth charts?

It helps predict growth patterns and identify any concerns if a child drops down two centiles.