Neonates

Question 1

Neonatal sepsis:
- Definition
- Risk factors (8)
- Causes organisms (5)
- Pathophysiology
- Red flags (6)
- Symptoms
- Investigations (3)
- Management
- DD (4)
- Extra facts - late onset LONS

Answer 1

Neonatal sepsis:

• Definition: early onset neonatal sepsis EONS is sepsis occurring 48-72 hours of life
• Risk factors: preterm birth after spontaneous labour, low birth weight, maternal group b strep infection, prelabour rupture of membranes, invasive group b strep infection in previous baby, chorioamnioitis, red flags (parenteral abx treatment to mum for bacterial infection during labour or 24 hours before/after birth, suspected infection in other baby if multiple preg)
• Causes organisms: group b strep (in 25% womens genital tract), ecoli, coag - staph, h influ, listeria monocytogenes
• Pathophysiology: via ascending infection in mum with chorioamnionitis/ perinatally via direct contact in birth canal / haematogenous spread
• Red flags: systemic abx given to mum for bacterial infection within 24 hours of birth, seizures, signs shock, resp distress >4 hours after birth, need for mechanical ventilation in term baby, cotwin suspected infection
• Symptoms: altered responsiveness/behaviour, feeding intolerance, altered muscle tone, abnormal HR, resp distress signs, reduced oxy sats, jaundice, apnoea, signs neonatal encephalopathy, need for cardio-pul resus, need for mech vent, persistent pul htn, temp abnormal, oligouria after 24 hours, metab acidosis, abnormal glucose, unexplained bleeding/clotting INR >2
  Early infection: resp distress, pneumonia, septicaemia
  Late (72hrs): septicaemia +/- meningitis
• Investigations: bloods (fbc, crp (repeat in 18-24hrs), blood cultures), swabs, LP before abx if strong suspicion meningitis
• Management: IV benzylpenicillin w gentamicin 7-10 days or 14 days if csf +. If CRP high but cultures - then 5 days abx. Stop at 36 hours if cultures - and clinical suspicion - and crp ok.
  If any 1 risk factor or clinical feature monitor for 12 hours, if any 2 start abx within 1 hour
• DD: transient tachypnoea of newborn, resp distress syndrome, meconium aspiration, hemolytic disease newborn
• Extra facts: LNOS: 7-28 days usually staph epidermis

Question 2

Necrotising enterocolitis:
- Definition
- Pathophysiolgy
- Risk factors (5)
- Symptoms (9)
- DD (5)
- Investigations
- Management
- Complications (5)

Answer 2

Necrotising enterocolitis:

• Definition: injury to the intestines ranging from mucosal damage to necosis + perforation usually presenting within first 3 weeks in life in premature neonates
• Pathophysiology: innate immune response to microbiota of premature infants gut leading to inflammation + injury
• Risk factors: low birth weight, preterm, formula feeding, intrauterine growth restriction, exchange transfusion, acute hypoxia, poor intestinal perfusion
• Symptoms: feeding intolerance, vomit (bile or blood stained), abdo distension, absent bowel sounds, haematochezia, if severe: erythema, palp bowel loops, apnoea, lethargic, bradycardia, peripheral cyanosis
• DD: sepsis, hirsprungs, volvulus, malrotation, gor
• Investigations: axr (distended bowel loops, thickened bowel wall (bowel oedema), gas in bowel wall (pneumatosis intestinalis), pneumoperitoneum if perf). Is staged via bell scoring system based on axr + clinical f
• Management: antenatal steroids if anticipate premature, encourage breast feeding, delayed cord clamping at birth. NBM + NG tube, If bell 1+2 withold oral feeds 10-14 days and give parenteral, 10-14 days iv abx, vent support, fluid resus, inotropic support. Emergency surgical if perforation/stricture/deterioration and is mostly resection with stoma
• Complications: perf, sepsis, death. Long term is stricture, short bowel syndrome

Question 3

Hypoxic ischaemic encephalopathy:
- Definition
- Risk factors (3)
- Causes (4)
- Symptoms (5)
- Investigations (3)
- Management
- Complications (3)
- Extra facts: sarnat staging classificationu

Answer 3

Hypoxic ischaemic encephalopathy:

• Definition: brain damage to neonates due to hypoxia (lack of oxy) during perinatal or intrapartum period which can be permanent causing cerebral palsy
• Risk factors: traumatic birth, acidosis on the umbilical artery blood gas, cardiac abnormality, emergency c section, bp extremes in mum
• Causes: maternal shock, intrapartum haemorrhage, prolapsed cord causing compression of cord during birth, nuchal cord where cord wrapped around neck
• Symptoms: extremely alert/non arouseable, trouble breathing, seizures, can’t feed, development delays
• Investigations: oxygen sats, blood gas, echo, suspect when symptoms + time of labour
• Management: nutrition, metab correction, ventilation support, therapeutic hypothermia within 6 hours of birth for 72 hours where cooled to 34C to reduce inflammation and neurone loss improving neuro developmental + neurological outcomes
• Complications: epilepsy, adhd, cerebral palsy
• Extra facts: Sarnat staging classification
  Mild: poor feeding/irritable/hyperalert resolves in 24 hours
  Mod: poor feed/lethargic/hypotonic/seizures taking weeks to resolve, 40% develop cere pal
  Sev: reduced consciousn, apnoeas/flaccid/absent reflexes, 90% cerebral, 50% mort

Question 4

Neonatal jaundice:

• Causes
• Complications
• Risk factors
• Management