Preterm Infant Flashcards
Preterm?
A birth that occurs before 37 completed weeks of gestation
Term?
A birth between 37 weeks and 42 weeks of gestation
Post-term?
A birth that occurs after 42 completed weeks of gestation
What % of all pregnancies are preterm?
6-7%
Over a half of deaths in childhood occur during the first year of life and are influenced strongly by …
- Preterm delivery
* LBW
The number of preterm births globally rises every year due to …
- Increasing maternal age
- Increasing rate in pregnancy related complications
- Greater use of infertility treatments
- More c-sections
What is the biggest cause of preterm birth?
Spontaneous
Women with a ________ pregnancy are much more likely to give birth early
Multiple
> 2 previous preterm deliveries increases the risk of another preterm delivery by __%
70
An abnormally shaped _______ can increase the chances of giving birth early
Uterus
An interval of less < 6 months between pregnancies increases the risk of giving birth early
TRUE
Conceiving through IVF makes you less likely to give birth early
FALSE - more likely to have a preterm brith
Smoking, drinking alcohol and using illicit drugs make you more likely to have a ________ birth
Preterm
Multiple miscarriages/ abortions make you more likely to have a ________ birth
Preterm
** Delay cord clamping if possible in a preterm baby– they have very little amounts of blood !! **
TRUE
You must keep preterm babies warm, they get cold very easily
:((((
Low admission ___________ is an independent risk factor for neonatal death
Temperature
Thermal regulation of the preterm is ineffective due to …
- Low BMR
- Minimal muscular activity
- No SC fat for insulation
- Surface area : body mass ratio is very high
By what 4 methods do babies lose heat?
Convection – box prevents this
Radiation – heat inside the box
Evaporation – plastic bag + humidity
Conduction – box with insulated mattress
List 4 methods of keeping a baby warm.
- Skin to skin
- Wrap or bags
- Prewarmed incubator
- Transwarmer mattress
Why is the an increased risk of nutritional compromise (calorie deficit) in preterm infants?
- Limited nutrient reserves
- Gut immaturity
- Immature metabolic pathways
- Increased nutrient demands
What is early onset neonatal sepsis usually due to?
Bacteria acquired before or during labour
What is late onset neonatal sepsis usually due to?
Bacteria acquired after delivery
What babies are more at risk of infection?
Preterm babies
Name the 2 most common early onset neonatal sepsis organisms.
- Group B Streptococcus
* Gram negatives
Name the 4 most common late onset neonatal sepsis organisms.
- Coagulase negative staphylococci
- Gram negatives
- Staph aureus
- Group B Streptococcus
Why are premature babies more likely to get sepsis?
- Immature immune system.
- Intensive care environment.
- Indwelling tubes and lines.
What commonly used machine in the wards increases a babies risk of infection?
INTUBATORS!!
** When a baby gets sick, if they are premature then their bone marrow cannot make WBC’s
In sick premature babies, what happens to WBC count?
FALLS
What is different about the retina of a preterm baby?
It is not vascularised
List the 3 most common resp complications of newborns.
- Respiratory distress syndrome (RDS) – surfactant deficiency
- Apnoea of prematurity
- Bronchopulmonary dysplasia
RDS is common in ________ babies
Preterm
What is RDS a problem of?
Hyaline membranes
Describe the primary pathology of RDS.
- Surfactant deficiency
* Structural immaturity
Describe the secondary pathology of RDS.
- Alveolar damage
- Formation of exudate from leaky capillaries
- Inflammation
- Repair
What is the classical x-ray sign in RDS?
Ground glass
List the signs of RDS.
- Tachypnoea
- Grunting
- Intercostal recessions
- Nasal flaring
- Cyanosis
- Worsening over minutes to hours !!
Describe the series of events in RDS.
Gradual worsening to a nadir at 2-4 days then gradual improvement
Outline the management of RDS.
- Maternal steroid
- Surfactant
- Ventilation – invasive/non-invasive
On an x-ray of a baby with severe RDS, what will be practically impossible to see?
Heart border
Necrotising enterocolitis is a neonatal ________ __________
Surgical emergency
What is necrotising entercolitis?
Necrosis in the small and large intestine !! – multifactorial bowel infection
What does a baby always have before getting necrotising entercolitis?
Milk
Free gas in the bowel wall gives tramlining appearance
What condition is this seen in?
Necrotising enterocolitis
Babies who get necrotising enterocolitis are usually recovering from what condition?
RDS
What are the early signs of necrotising enterocolitis?
Lethargy and gastric residuals
What is seen in the bowel wall of a baby with NE?
Necrotic areas + abscesses
List the 4 main signs of NE.
Blood stool, temperature instability, apnoea and bradycardia
Who is at risk of PDA (patent ductus arteriosus)?
Preterm babies
What are the 3 consequences of failure of the ductus arteriosus to close after birth?
- Leads to symptoms of congestive heart failure
- Oxygen requirements are high
- Exacerbates RDS
Explain the 6 stages of closure of the ductus arteriosus.
- Baby is born and takes first breath
- Lungs starts working
- Pulmonary resistance decreases
- Pumonary vascular resistance drops and blood flows into the lungs
- Foramen ovale closes at same time systemic vascular resistance increases
- Less blood flows through ductus arteriosus and it closes (+ there is prostaglandin decrease)
MACHINE LIKE MURMUR
Patent Ductus Arteriosus
What is the most common clinical sign in PDA?
Machine like murmur !!!
Outline 3 signs seen in PDA.
- Cardiomegaly
- Poor feeding
- Increased systolic pressure
Describe intraventricular haemorrhage.
- Cardiomegaly
- Poor feeding
- Increased systolic pressure
In 80% of cases, ____ leads to an intraventricular bleed
GMH
1st line Ix for intraventricular haemorrhage?
USS
How can the risk of bleeding in intraventricular haemorrhage be greatly reduced?
Surfactant
How can the risk of bleeding in intraventricular haemorrhage be greatly reduced?
Surfactant
Grade 1/2 intraventricular haemorrhage ….
- Neurodevelopmental delay up to 20%
* Mortality 10%
Grade 3/4 intraventricular haemorrhage ….
- Neurodevelopmental delay up to 80%
* Mortality 50%
How can IVH be prevented?
- Antenatal steroids.
- Prompt and appropriate resuscitation.
- Avoid haemodynamic instability.
What 4 H’s should you avoid when trying to prevent IVH?
hypoxia
hypercarbia
hyperoxia
hypocarbia
What is there an inverse relationship between in IVH?
Gestational age at birth
What are the 2 major risk factors for IVH?
- Prematurity.
* Respiratory distress syndrome.
When do most IVH’s occur?
In the first day of life.
In up to 90% of neonates who will get GMH-IVH, the insult is present by 72 hours.
Why does RDS increase the risk of IVH?
Hypoxia, acidosis and hypotension increase the likelihood of the cerebral circulation being unstable.
