Teachings Flashcards
What is the most common reason for admission to NICU?
Respiratory distress
What are the causes of respiratory distress in a newborn?
Respiratory Cardiac Sepsis Surgical Metabolic
What is the clinical presentation of respiratory distress?
Cyanosis Grunting Tachypnoea Nasal flaring Head bobbing Recessions Use of accessory muscles Poor feeding and lethargy Poor blood O2 sats Hypercapnia and hypoxaemia on blood gas CXR changes
What are the respiratory causes of distress?
Resp distress syndrome Meconium aspiration syndrome Congenital pneumonia (bacterial/viral) Pneumothorax Persistent pulmonary hypertension Transient tachypnoea of newborn Delayed postnatal adaptation
What are the cardiovascular causes of respiratory distress?
Patent ductus arteriosus
Congenital cardiac anomaly (heart failure/ coarctation)
Anaemia
Hypotension
What are the congenital malformations that cause resp distress?
Choanal atresia Pierre Robin Syndrome Laryngobronchomalacia Subglottic stenosis Diaphragmatic hernia Tracheo eosophageal fistula Congenital lung malformation (congenital cystic adenomatoid malformation, lobar emphysema, bronchogenic cyst) Pulmonary hypoplasia
What is the other name for respiratory distress syndrome?
Hyaline membrane disease
What is the most common cause of respiratory distress syndrome in preterm and low birthweight neonates?
Incomplete lung development
Deficiency of surfactant
Correlates with structural and functional immaturity
What is the rate of RDS in different ages/gender?
50% of infants born before 28 weeks have RDS
30% of infants between 28 and 34 have RDS
5% of infants in more than 34 weeks
More common in boys
Incidence is 6x higher in mothers with diabetes due to a delayed pulmonary maturation.
What is the pathophysiology of respiratory distress syndrome?
Immature type 2 pneumocytes produce less surfactant
Increase in surface tension and decrease in compliance
Results in atelectasis with pulmonary vascular constriction, hypoperfusion abd lung tissue ischaemja
Hyaline membrane forms through a comb of sloughed epithelium, protein and oedema.
What would you see on xray of respiratory distress syndrome?
Air bronchograms
Ground glass appearance
What is the treatment of respiratory distress syndrome?
They are lacking surfactant
Positive pressure ventilation, especially provision of PEEP
Gentle ventilation (this is to prevent barotrauma and volutrauma
How can you decrease the number of neonates with respiratory distress syndrome?
Antenatal steroids
Careful decisions regarding early delivery
Early recruitment of the lungs by the appropriate sue of PEEP during resuscitation and gentler ventilation
Early use of surfactant and repeat doses depending on need
Supportive treatment- management of fluid balance, PDA and nutrition
What is the pathophysiology behind meconium aspiration syndrome?
Meconium passage may represent inutero hypoxia or fetal distress
When aspirated the meconium can induce hypoxia a number of ways...m . Airway obstruction . Surfactant dysfunction . Chemical pneumonitis . Persistent pulmonary hypertension
How does meconium aspiration lead to perinatal infection?
Meconium alters the amniotic fluid, reducing its antibacterial activity and therefore subsequently increasing the perinatal infection risk.
What is the presentation of meconium aspiration?
Infants can be very sick needing extensive resuscitation at birth, intubation and ventilation
They can be asymptomatic at birth and then become symptomatic after several hours
May have yellow green staining of the skin, umbilical cord and nails
Respiratory symptoms
What would you see on a CXR of meconium aspiration?
Bilateral homogenous air space shadowing
Areas of atelectasis
Areas of air trapping
What is the treatment of meconium aspiration?
The neonatal team should be present at the time of the delivery
If the baby is vigorous with normal heart rate and breathing…
Then the meconium is nor causing airway obstruction and therefore there will be no advantage of suctioning, meconium observation should take place
If the baby is not vigorous…
the oropharynx and trachea should be suctioned under direct vision
And also it is important to remove the mechanical obstruction
Baby should recieve optimal ventilation, administratuon of surfactant, management of persistent pulmonary hypertension (with Nitric oxide, high flow oxygen ventilation), hypotension, fluid balance
ABX administration
What is the most common causes of respiratory distress in the newborn and who is it more common in?
Transient tachypnoea of newborn
It constitutes 40% of the cases
Infants are usually full term or near term
More common in:
Male infants
Infants born after precipitous delivery or by caesarean
Macrosomic infant of diabetic mothers
What is the pathophysiology behind transient tachypnoea of the newborn?
It is a benign condition caused by residual fluid in the neonatal lung tissue after birth.
Prostaglandins released during and after delivery help to dilate the lymphatic vessels which remove lung fluid as baby takes the first few breaths.
What is the clinical picture of transient tachypnoea of the newborn?
Respiratory distress in a term/near term infant which starts immediately after birth or within two hours
The baby will have no risk factors for sepsis, no history of meconium stained liquor and normal antenatal scans
The distress usually lasts for 24-48 hours with gradual improvement in symptoms
What is the treatment for transient tachypnoea?
Supportive and close observation
Self limiting disease
Low flow oxygen may be needed
Antenatal administration of steroids 48 hours before elective c section decreases the risk of TTN
Its important to rule out other causes of resp distress and it is a diagnosis of exclusion
What are the causes of pneumonia?
Congenital pneumonia- haematogenous spread from mother, ascending infection, in utero aspiraton
Intrapartum pneumonia
Postnatal pneumonia
Colonisation of the respiratory tract with pathogen of maternal or environmental origin
Ventilated neonates
When do respiratory symptoms usually start in pneumonia?
Usually start within 24-72 hours
There can be a delayed onset
What is the treatment of oneumonia?
Prompt diagnosis
Treatment is either with antibiotics or antivirals
Look for disseminated infection to other sites (blood and CSF).
