Neonatology Flashcards
Embryo defintion
Fertilised ovum, until 9w
Fetus definition
fertilised ovum, from 9w until delivery
Still birth definition
fetal death and expulsion >24w
Abortion definition
fetal death <24w
Neonatal mortality rate
number of deaths of LIVE born infants within the 1st 28 days per 1000 live births
Infant mortality rate
number of deaths between birth and 1 year per 1000 live births
Perinatal mortality rate
number of still births and early neonatal deaths within the first 7 days per 1000 live AND still births
Low birth weight
<1500g
Presentation of CMV infection
CNS - periventricular calcification
Ophthal - chorioretinitis
Sensorineural deafness
Hepatosplenomegaly
Jaundice
Pneumonitis
Thrombocytopenia with petechia +/- purpura
Rx CMV
oral valganciclovir or IV ganciclovir
Ix CMV
PCR amplification for viral DNA
- amniotic fluid/blood/urine/CSF or saliva
Classic triad of toxoplasmosis
Hydrocephalus
Chorioretinitis
Diffuse intracranial calcifications
Ix for toxoplasmosis
Reference serology test
- IgM and IgG
IgM +ve indicates active infection
IgG becomes +ve after 2w and stay +ve for life
Rx for toxoplasmosis
If fetal infection status not known
- Spiramycin
- Cont until term of fetal infection status documented
If fetal infection suspected or documented
- Pyrimethamine / Sulfasdiazine / Folinic acid
- Rx until 12m of age
Presentation congenital syphilis
Rash
Desquamation of soles of hands & feet
Metaphyseal bone lesions
Other features same as toxoplasmosis/CMV
Fetal varicella syndrome features
Limb hypoplasia
Microcephaly
Cataracts
Skin scarring (pale yellow dermatomal scars)
IUGR
Rx fetal varicella
Prophylaxis
- IVIG following exposure
Rx
- IV aciclovir
Complications of fetal varicella
2y bacterial infection (strep A)
Thrombocytopenia
Pneumonia
Purpura fulminans - subcut vasculitis
Cerebellitis
Congenital parvovirus causes …?
red cell aplasia > hydrops fetalis
Physioogy of PPHN
failure of pulmonary vascular resistance to fall within the infants first breaths, so the fetal pattern of left to right shunting across the FO and DA persists, so intrapulmonary shunting and further hypoxia occurs
Ix for haemorrhagic disease of the newborn
Prolonged PT and APTT
FBC - normal platelets and fibrinogen
Clotting factors II, VII, IX and X all low
Rx of haemorrhagic disease of the newborn
Vit K and FFP (need FFP becuase Vit K doesnt correct clotting times quickly enough
Newborn hearing screening
- Automated otoacoustic emissions test
- Automated auditory brain stem response (AABR)
When does blood spot in CF babies become unreliable
if done after 8w
when to do blood spot if baby needs transfusion after birth
pre-transfusion and 3 days after the last transfusion
unavoidable repeat sampling of blood spot
<32 weeks - need repeat day 21
Bortderline TSH results - repeat day 7-10 after 1st sample
Gestation indicated for antenatal steroids
24 - 34+6 weeks
survival rates of premature infants with active care
<21w - 0%
22w -10%
23w - 40%
24w - 60%
26w - 80%
dose regime of antenatal steroids
betamethasone 12mg - 2 doses 2x hours apart
dexamethasone 6mg - 4 doses 12 hours apart
gestation indicated for antenatal Mg sulf
< 32 w
Most common organism causing EOS
Group B strep - Streptococcus agalactiae
Screening criteria for ROP
<31 weeks gestational age OR <1500g BW
Timing of 1st screen for ROP
If born < 31 weeks -
Between 31+0 and 31+6 postmenstrual age, or at 4w completed weeks postnatal age (whichever is LATER)
If born >31 weeks and < 1500g -
36 weeks postmenstrual age, or 4 weeks postnatal age (whichever is SOONER)
Pathophysiology of ROP
Secondary to interruption of the normal process of retinal blood vessel development following preterm birth
- Hyperoxia has a detrimental effect on the immature retina
- Retinal ischaemia drives vaso-proliferation
Grading of IVH
I - restricted to subependymal/germinal matrix
II - expansion into the lateral ventricles but <50% and remain norma size
III - extension into dilated ventricles
IV - grade III with parenchymal haemorrhage
Most common affected sites in NEC
terminal ileum/caecum/ascending colon
Rx PDA
Prostaglandin synthase inhibitor - pcm or ibuprofen
Then surgical ligation if unsuccessful
surrogate measure for bilirubin production
carbon monoxide
breakdown products of haemoglobin
Fe
Globin
Carbon monoxide
Biliverdin
Interim product of haemoglobin breakdown to bilirubin
Biliverdin
What is used to break down haemoglobin to biliverdin
haem oxygenase
What is used to convert biliverdin to bilirubin
biliverdin reductase enzyme
What does unconjugated bilirubin join with in plasma
albumin
enzyme responsible for conjugating bilirubin in the liver
uridine disphosphate glucuronyl transferase (UGT)
what happens to conjugated bilirubin once it has been excreted in bile from the liver
it is hydrolysed in the gut to form urobilinogen and stercobilinogen. also is recycled into the enterohepatic circuation (most)
