Respiratory Distress Syndrome

Question 1

Who is at risk of HMD?

Answer 1

Preterm infantsInfants of diabetic mothers

Question 2

What is the pathophysiology of HMD?

Answer 2

Surfactant deficiency –> increased surface tension causes progressive atelectasis and increased effort of breathing

Question 3

What inhibits surfactant production?

Answer 3

Hypoxia, hypothermia and acidosis

Question 4

What is the natural history of HMD?

Answer 4

Respiratory distress soon after birth –> progressively worsens in next 72 hours –> improves after then as baby starts producing surfactant Usually resolves within one week

Question 5

What are the typical clinical features of HMD?

Answer 5

Preterm infantInactivePoor tone- frog positionOedematous

Question 6

What are the CXR features of HMD?

Answer 6

Under expanded lungsBilateral diffuse reticular-granular ‘ground-glass’ infiltrates Air-bronchograms

Question 7

What are the 6 complications of HMD?

Answer 7

Respiratory failureChronic lung disease2ry bacterial pneumoniaPDA–> cardiac failurePeri- and intraventricular haemorrhage Pneumothorax

Question 8

How to prevent HMD?

Answer 8

Avoid preterm labour and elective C/S before 39/40BMZ if

Question 9

What are the 5 parameters in managing HMD?

Answer 9

Relieve hypoxiaClose monitoringTemperature controlNutritionCorrect acidosis

Question 10

How is hypoxia relieved in HMD?

Answer 10

Respiratory support given- NPO2–> CPAP –> IPPV–> HFOVOxygen therapy - monitored sats (88-92), FiO2, paO2 (7-10kPa)Surfactant replacement therapy (in&out)

Question 11

How is temperature controlled in HMD and what is the aim?

Answer 11

Incubator temperature between 31-34*CAim to maintain neutral thermal environment as to minimize oxygen requirement

Question 12

What parameters and monitored?

Answer 12

BP (inotropes given if needed)Hb (blood transfusion if needed)Heart rateTemperatureGlucoseSaturations

Question 13

What is the nutrition plan for an infant with HMD?

Answer 13

IV fluids, electrolytes and energy requirements ASAPMilk feeds via nasogastric tube if infant tolerates themTotal parenteral nutrition (TPN) if unable to tolerate feeds

Question 14

How is acidosis in HMD corrected if respiratory in origin?

Answer 14

If respiratory acidosis, it is caused by increased paCO2, therefore corrects by improving ventilation.Mild respiratory acidosis is usually tolerate and ventilation not needed.

Question 15

How is acidosis in HMD treated if metabolic in origin?

Answer 15

If metabolic acidosis, then should improve with adequate ventilation and hydration.

Question 16

What is believed tap cause TTN?

Answer 16

Delayed clearing of fetal lung fluid into the pulmonary capillaries and lymphatics after delivery –> interferes with gas exchange and increased the work of breathing

Question 17

Who is at risk of TTN?

Answer 17

Term infants born by elective C/S Can affect prems and NVDs

Question 18

What is the natural history of TTN?

Answer 18

Respiratory distress within 1-2 hours of birth –> Improves within 24-48 hours, but tachypnoea can last for a few days

Question 19

What are the clinical features of TTN?

Answer 19

Hyper inflated chestRespiratory support may be needed but O2 usually not >40%IPPV not usually needed

Question 20

What are the CXR findings in TTN?

Answer 20

Normal lung volume but increased vascular markings Prominent hilar streakingFluid in lung fissures

Question 21

How do you manage an infant with TTN?

Answer 21

Monitor closelyRespiratory support as neededSupportive measures as needed, but usually systemically well

Question 22

Who is at risk of meconium aspiration?

Answer 22

Term or post-term infants who become stressed in utero

Question 23

What increases the risk of meconium aspiration?

Answer 23

Infant that is wasted or UGA

Question 24

When is the meconium aspirated?

Answer 24

Either at delivery or during gasping in utero when stressed

Question 25

What are the two clinical sequelae following meconium aspiration and how do they arise?

Answer 25

Chemical irritation --> pneumonitisParticulate matter blocks bronchi and bronchioles --> areas of emphysema and atelectasis

Question 26

What are the 6 complications of meconium aspiration?

Answer 26

Respiratory failurePneumomediastinum or pneumothoraxHIEPPHN2ry bacterial infectionChronic lung disease

Question 27

What are the clues pointing toward meconium aspiration?

Answer 27

Meconium staining of the placenta and cord, skin and nails

Question 28

What are the CXR features of meconium aspiration?

Answer 28

Hyper inflated chestPatchy areas of collapse and overdistensionSigns of complications such as PTX

Question 29

When do you suction an infant?

Answer 29

When there is evidence of meconium staining, and the infant when delivered is not vivacious or breathing.

Question 30

If an infant is meconium stained, and cries well after deliver, do you suction the infant?

Answer 30

No

Question 31

An infant born after signs of fetal distress is delivered floppy and not breathing, what is the immediate management?

Answer 31

Resus the infant. If meconium evident, suction the mouth then the nose, and then dry the infant to stimulate respiration. Continue with resus algorithm if no response.

Question 32

How is suction performed?

Answer 32

Large bore catheter used, 8/10FInserted to 5cm for 5 secondsSuction pressure

Question 33

What can occur if infant is suctioned too vigorously?

Answer 33

Vagal bradycardia LaryngospasmDelayed onset of breathing

Question 34

How do you manage an infant with meconium aspiration?

Answer 34

Suction if indicatedProvide respiratory support as neededGastric lavage - 2% sodium bicarbonate to prevent gastritisGeneral supportive measuresSurfactant may be beneficialMonitor closely Antibiotics if needed

Question 35

What are the ideal saturation a for a baby with meconium aspiration and why?

Answer 35

>95%. You want to prevent the infant developing PPHN and there are fewer risks of O2 toxicity in term infants.

Question 36

Why can surfactant be beneficial in an infant with meconium aspiration?

Answer 36

Condition can lead to secondary surfactant deficiency due to the hypoxia

Question 37

Which infants are at risk for developing pneumonia?

Answer 37

PROM >18 hoursPPROMPTLChorioamnionitisMaternal untreated chronic infection, such as syphilis

Question 38

What are the signs of chorioamnionitis?

Answer 38

Maternal pyrexiaFoul smelling liquorFetal tachycardiaUterine tendernessLeucocytosis

Question 39

How do you differentiate between nocosomial pneumonia and pneumonia contracted from the mother?

Answer 39

An infant who contracts pneumonia from the mother develops signs in the first 72 hours, where as a nocosomial pneumonia develops after 72 hours

Question 40

What is the pathogenesis of a maternal,y acquired pneumonia?

Answer 40

The infant is exposed to organisms in utero or during passage through the birth canal

Question 41

What are the most likely causes of a congenital pneumonia?

Answer 41

E. ColiGroup B streptococcus Chronic infections suchas syphilis, rubella, CMV.

Question 42

What are the most likely causes of nocosomial pneumonia?

Answer 42

Staph aureusKlebsiellaPseudomonas

Question 43

How would an infant with pneumonia clinically present?

Answer 43

Apnoeic spellsRespiratory distressSepticaemia

Question 44

How does septicaemia present in a neonate?

Answer 44

LethargyPoor tonePoor handling Poor perfusionAbdominal distention (septic ileus) Vomiting

Question 45

What are the complications of pneumonia in the neonate?

Answer 45

SepticaemiaRespiratory failureChronic lung disease

Question 46

What is the management plan for an infant with pneumonia?

Answer 46

Septic screenAntibioticsGeneral supportive measuresRespiratory support

Question 47

What does a septic screen involve?

Answer 47

Blood cultureFull blood count with differentialCRP

Question 48

How would you use antibiotics to treat a neonate with pneumonia?

Answer 48

Start with empiric broad spectrum antibiotics, then use more specific antibiotic once organism organism identified, using rx that is specific to local resistance patterns

Question 49

What are the CXR findings in an infant with pneumonia?

Answer 49

Similar to HMD, especially if GBSPatchy distribution of consolidation and infiltratesAir-bronchograms

Question 50

Signs needed to diagnose RDS

Answer 50

``` Two or more of: Tachypnoea >60 Central cyanosis (room air) Grunting Sternocostal recession ```

Question 51

Respiratory causes of RDS

Answer 51

- HMD - TTN - MAS - pneumonia - Chronic lung disease - Pneumothorax - Lung hypoplasia

Question 52

Non-respiratory causes of RDS

Answer 52

``` Hypothermia Metabolic acidosis Anaemia Polycythemia PDA Heart disease Diaphragmatic hernia ```

Question 53

Causes on pneumothorax in neonate

Answer 53

MAS HMD Vigorous resuscitation after birth