Term & Preterm Infants Flashcards
At what weeks is a baby considered... -Term -Preterm -Post-term ?
Term: 37-42 weeks
Preterm: before 37 weeks
Post-term: after 42 weeks
As preterm is the widest spectrum, it is split into 3 groups again. What are these?
Extremely preterm (22-<28 weeks)
Very preterm (28-<32 weeks)
Moderate/late preterm (32-<37 weeks)
What newborn weight is considered... -Normal -Small for gestational age (SGA) -Large for gestational age (LGA) ?
Normal: 2.5 - 4.0kg
SGA: <2.5kg
LGA: >4.0kg
The most rapid increase in fat mass occurs in the 1st trimester. T/F?
False
Build-up of fat occurs most rapidly in the 3rd trimester - esp. the last 4 weeks of pregnancy
This is a problem in preterm babies
List some physical differences you may notice in a preterm baby as opposed to a term baby (3)
- Thinner due to less fat, may see bones
- Arms lying flat at sides, not flexed up, due to less muscle
- Pinker in colour as less SC fat means capillary beds are more visible through the skin
Why may a baby become acidotic during prolonged labour?
- Womb contractions reduce O2 delivery down the placenta
- Foetal Hb releases O2, but prolonged labour can deplete foetal reserves and lead to acidosis
What 2 hormones can enhance foetal adaptation to the hypoxic environment of labour?
Cortisol
+
Adrenaline
Describe perinatal adaptation
- Baby takes first breath/cries
- Lungs expand and open alveoli
- Foetal circulation changes to newborn circulation
- Pulmonary arterial blood pressure decreases
- PaO2 (partial pressure of O2 in arterial blood) increases)
The ? score is an objective measure of perinatal adaption
Apgar score
What are the 5 considerations in the Apgar score?
Colour (Appearance) Heart rate (Pulse) Responsiveness (Grimace) Tone (Activity) Resp rate (Resp rate)
*spells out Apgar
Describe how the Apgar score is calculated
- Each component (HR, RR, responsiveness, tone, colour) is given a score from 0-2
- 0 = not present, 1 = abnormal, 2 = abnormal
- Normal score is >=8 /10
Why is skin-to-skin contact with the parents so important immediately after birth? (3)
- Babies get cold easily so it helps keep them warm (alongside blanket, hat etc)
- Establishes breastfeeding
- Helps form hormonal and emotional attachment between parents and baby
Why are all babies given vitamin K after birth?
To prevent haemorrhagic disease of the newborn
Which maternal infections carry risk of infecting the baby? (6)
- Hep B
- Hep C
- HIV
- Syphilis
- TB
- Group B Strep
At birth, which infections may the baby be vaccinated against if the mother has them? (2)
Hep B (immunoglobulin treatment may also be required but vaccine usually enough)
TB (BCG vaccine)
Name 2 vaccines which a pregnant woman can receive
Influenza vaccine (as pregnancy can cause worse illness)
Pertussis vaccine (to provide antibodies against Pertussis for the growing baby)
What screening tests are carried our for newborns and when?
- Newborn physical examination (within first 3 days)
- Blood spot test (~ 5 days)
- Universal hearing screening (birth to 4 weeks)
What conditions does the blood spot test currently check for? (4)
- CF
- Congenital hypothyroidism
- Sickle cell disorder
- Inherited metabolic disease
What are some abnormalities of the head that may be seen in newborns? (7)
- Orofacial cleft
- Overlapping sutures
- Fontanelles (soft spots where sutures have not come together)
- Ventouse/forcep marks (from assisted delivery)
- Moulding (altered head shape from prolonged delivery)
- Cephalhaematoma (pool of blood under the scalp due to pressure during birth)
- Caput succcedaneum (swelling in the scalp due to pressure during birth)
What are some abnormalities that may be seen in the mouth of a newborn?
- Tongue tie
- Cleft lip or cleft palate (often seen together, cleft palate alone may be missed)
- Neonatal teeth (choking hazard so remove)
- Ebsteins pearls (keratin bumps in mouth, go away by themselves)
Facial palsy is often caused by…
Nerve compression during forceps delivery
What is meconium?
Baby’s first poo
How common is premature birth…
- In the UK
- Globally
UK: ~6% of births
Globally: >10%
Why is prematurity becoming more common worldwide? (4)
- Increasing maternal age
- Increasing rate in pregnancy complications
- Greater use of infertility treatments
- More C sections delivered before term
What are the most common causes of preterm birth? (4)
- Spontaneous preterm labour
- Multiple pregnancy
- Rupture of membranes
- Pregnancy associated hypertension
List risk factors for premature birth (7)
- > 2 previous preterm deliveries
- Abnormally shaped uterus
- Multiple pregnancy
- <6 months between 2 pregnancies
- IVF
- Smoking, alcohol, drugs
- Poor nutrition, hypertension, diabetes, multiple miscarriages
List 4 ways in which the preterm infant may be managed differently from a term baby
- Delayed cord clamping
- Bigger demand to keep warm
- Gentle lung inflation
- Monitor O2 sats closely
What extra measures may be used to keep a preterm infant warm? (4)
- Place immediately in a plastic bag to prevent heat loss
- Place under a radiant heater later
- Heat in prewarmed incubator
- Transwarmer mattress
Why must lung inflation have positive end expiratory pressure (PEEP)?
To keep the alveoli from collapsing
Complications risk increases in preterm birth with decreasing… (2)
- Gestational age
- Birth weight
List 7 common problems of prematurity
Hypothermia
Poor feeding/malnutrition
Infection/sepsis
Respiratory distress syndrome (RDS)
Patent ductus arteriosus (PDA)
Intraventricular haemorrhage (IVH)
Necrotising enterocolitis (NEC)
Why is hypothermia more common in preterm babies? (4)
- Low BMR
- Minimal muscle activity
- Negligible SC fat insulation
- High SA to body mass ratio
Why is nutritional compromise more common in premature babies?
- Limited nutrient reserves
- Gut immaturity
- Immature metabolic pathways
- Increased nutrient demands
Why can preterm babies not be fed immediately after birth?
Due to immature gut and metabolic pathways
How may a preterm baby be fed? (3)
- IV total parenteral nutrition
- Tube feeding (via NG or OG tube)
- Donor milk can be used until mother is able to provide her own breast milk
Why is formula not recommended before 34 weeks?
Due to immature metabolic pathways
But specially prescribed formula can be used if necessary
Why are babies born prematurely more at risk of infection? (3)
- Immature immune system
- Intensive care environment e.g., increased temp in incubator
- Indwelling tubes and catheters
What is the difference between early onset sepsis (EOS) and late onset sepsis (LOS)?
EOS: acquired before or during delivery
LOS: acquired after delivery
Which bacteria most commonly cause:
- early onset sepsis (EOS)
- late onset sepsis (LOS)
?
EOS:
- Group B Strep
- Gram -ves
LOS:
- Coagulase -ve staph
- Gram -ves
- Staph aureus
List 3 respiratory complications of prematurity
- Respiratory distress syndrome (RDS)
- Apnoea of prematurity
- Bronchopulmonary dysplasia
What is respiratory distress syndrome (RDS)?
Babies born at <34 weeks may not have produced enough surfactant to prevent the alveoli of the lungs from collapsing
Collapse leads to impaired gas exchange
What are the features of RDS?
Increased work of breathing Tachypnoea Grunting Intercostal recessions Nasal flaring Cyanosis
Worsens over minutes to hours, improves after 2-4 days
How is RDS managed?
Maternal steroid (beta- or dexa-methasone) to prevent RDS in anticipated preterm birth
Surfactant
Invasive/non-invasive ventilation
What is apnoea of prematurity and how is it managed?
Babies born at <34 weeks haven’t developed the part of the CNS which controls subconscious breathing, leading to periods of breathing cessation
This can be managed with a once-daily dose of caffeine to stimulate breathing mechanisms until these CNS centres develop in the next few weeks
What medication can be used to close a patent ductus arteriosus?
Indometacin
Ibuprofen
What is intraventricular haemorrhage?
Bleeding inside or around the ventricles of the brain (where the CSF is held)
Usually occurs within the first 72 hours of life
What is necrotizing enterocolitis?
Inflammation and death of the walls of the intestine, which can lead to perforation and infection
To monitor for retinopathy, premature babies should have their eyes checked how regularly?
Every 2 weeks for 6-8 weeks
The majority of childhood deaths occur when?
In the first year of life (majority within 28 days of birth)
Risk factors for infant death include…
- Increasing maternal age
- Smoking during pregnancy
- Poverty
- Prematurity
- Multiple birth
