NEO FINAL REVIEW

What is the cause of RDS?

Surfactant deficiency

What are the clinical signs of RDS?

• Tachypnea

• retractions

• grunting

What are the CXR findings of RDS?

• ground glass

• air bronchograms

What is the treatment of RDS?

• surfactant

• CPAP

• MV

What is the cause of TTN?

Delayed fluid absorption

What are the clinical signs of TTN?

• tachypnea

• mild distress

What are the CXR findings with TTN?

• Perihilar streaking

• hyperinflation

What is the treatment for TTN?

• O2

• CPAP

• supportive

What is the cause of MAS?

Meconium aspiration

What are the clinical signs of MAS?

• respiratory distress

• yellow skin

What are the CXR findings of MAS ?

• Patchy infiltrates

• hyperinflation

What is the treatment of MAS?

• O2

• ventilation

• iNO

What is the cause for BPD?

Chronic lung injury

What are the clinical signs of BPD?

• persistent O2 need

• wheezing

What are the CXR findings for BPD?

cystic changes

What is the treatment for BPD ?

• gentle MV

• nutrition

• bronchodilators

What is the cause of PPHN?

Persistent high PVR

What are the clinical signs of PPHN?

Cyanosis, SpO2 differential

What are the CXR findings of PPHN?

Normal or underinflated

What is the treatment for PPHN?

• O2

• iNO

• ECMO

A 30- week neonate presents with resp distress 4 hours after birth. ABG shows hypoxemia and respiratory acidosis. CXR shows diffuse ground-glass appearance. Infant is on CPAP with FiO2 of .40

What is the likely diagnosis ?

RDS

A 30- week neonate presents with resp distress 4 hours after birth. ABG shows hypoxemia and respiratory acidosis. CXR shows diffuse ground-glass appearance. Infant is on CPAP with FiO2 of .40

What should be your next step in respiratory management?

• mechanically ventilate

• Administer surfactant therapy

A 30- week neonate presents with resp distress 4 hours after birth. ABG shows hypoxemia and respiratory acidosis. CXR shows diffuse ground-glass appearance. Infant is on CPAP with FiO2 of .40

What are the risks of delayed surfactant therapy in this case?

• delayed surfactant can lead to alveolar collapse, hypoxia, increased vent requirements and increased risk of barotrauma

What are the risk factors for RDS in neonate?

• prematurity

• cesarean without labor

• maternal diabetes

• male sex

• white race

• perinatal asphyxia

• infection

What are the CXR findings in TTN vs RDS?

TTN:

perihilar streaking

fluid in fissures

hyperinflation

RDS:

Ground Glass

air bronchograms

Define mild Grade using jensen criteria

Need for <2 L/min nasal cannula

Define Moderate Grade using jensen criteria

> or equal to 2 L/min or CPAP/ NIPPV

Define Severe Grade using jensen criteria

Requieres invasive mechanical ventilation

What is the treatment for apnea of prematurity?

• caffeine citrate

• tactile stimulation

• CPAP

• mechanical ventilation if needed

Name two complications of mechanical ventilation that can lead to air leaks ?

• PIE- Pulmonary interstitial emphysema

• Alveolar overdistension— rupture——- air leaks

Which of the following is most associated with delayed fetal lung fluid clearance?

• MAS

• RDS

• TTN

• Pneumonia

TTN

What is the primary diagnostic test for PPHN?

Echocardiogram

What surfactant-related issue is associated with MAS?

Surfactant washout and inactivation

Which treatment is first-line for apnea of prematurity?

Caffeine citrate

What is the most common radiographic finding in PIE?

bubbly lucencies

Low- Flow Nasal Cannula

Delivers variable FiO2: flow < or equal to 2 L/min

RAM cannula

Can be used for NIV; fills up to 60-80% of nares

Vapotherm

High velocity flushes dead space

Oxygen Hood

Requires high flow to flush CO2; stable FiO2

High Flow Nasal Cannula HFNC

Heated, humidified gas > or equal to inspiratory flow

A neonate on HFNC therapy suddenly exhibits increased WOB FiO2 is 50% , flow is 6 L/min and SpO2 drops to 86%

What are 2 possible causes of desaturation in this patient?

• not getting all of the FIO2

• flow can go up to 8

• the cannula is displaced or can be occluded

A neonate on HFNC therapy suddenly exhibits increased WOB FiO2 is 50% , flow is 6 L/min and SpO2 drops to 86%

What adjustments might you consider to optimize therapy?

• increase flow

• increase FiO2

• reassess prong fit or suction

A neonate on HFNC therapy suddenly exhibits increased WOB FiO2 is 50% , flow is 6 L/min and SpO2 drops to 86%

Would switching to nCPAP be appropriate in this case? why or why not?

Yes, it will help decrease WOB and stabilize FiO2 CPAP provides that positive pressure

What is the minimum SpO2 and PaO2 threshold to treat hypoxemia in VLBW neonates?

• SpO2 < 88%

• PaO2 < 50 mmHg

What defines HFNC therapy compared to LFNC in neonates?

Low flow nasal cannula is not heated while a HFNC is heated and humidified

Which device is FDA approved for warming/ humidifying gases but not labeled for delivering distending pressure?

RAM Cannula

What flow rate is required for an oxygen hood to prevent CO2 rebreathing?

High gas flow

• standard is 6-8

• minium is 8

What are two limitations of HFNC in neonates?

• inability to consistently predict delivered FiO2

• inability to consistently predict continuous distending pressure

• gas flow is delivered directly into the infants nares

• few quality studies on the effectiveness

What is a key requirement when delivering High Flow Nasal Cannula ( HFNC) therapy to neonates?

Heating and humidifying the delivered gas

When using an oxyhood where should the oxygen analyzer be placed?

Close to the baby’s face

The infant weighs 6 kg. What is the estimated inspiratory flow requirement?

5.4 L/min

The infant weighs 3 kg. What is the estimated inspiratory flow requirement?

10.8 L/min

LFNC Flow Rate

0.1 to < or equal to 2 L/ min

LFNC FiO2 control

use of a blender to control FiO2 source

• delivered FiO2 variable based on the patients min ventilation

LFNC Humidification required?

Yes cool, bubble bottle humidity

LFNC unique feature

lightweight, flexible and resistance to liquids

HFNC Flow rate

1-8 L/min

> 1 L/min

HFNC FiO2 control

Blender

21-100%

HFNC Humidification requiered?

Yes, heated

HFNC unique feature

delivers heated and humidified oxygen

Oxygen hood Flow Rate

> or equal to 8 L/min

Oxygen Hood FiO2 control

stable FiO2

blender

• 25% to 90%

Oxygen Hood Humidification Required ?

Yes, heated

Oxygen Hood Unique Feature

• Body is still accessible

• transparent enclosure

Vapotherm Flow Rate

1-8 L/min

Vapotherm FiO2 control

precise FiO2

blender

21-100%

Vapotherm Humidification Required?

Humidification required, heated

Vapotherm unique Feature

high velocity

RAM Cannula Flow Rate

1-8 L/min

RAM Cannula FiO2 control

21-100%

Blender

RAM Cannula Humidification required?

Yes, heated

RAM Cannula unique feature?

Prongs are larger bore than conventional or high flow cannulas

• Prongs may take up to 60-80% of the nare space

SP-A Primary Role

Host defense and regulation of surfactant

SP-C Primary Role

Enhances spreading of phospholipids

SP-B Primary Role

Requiered for spreading and stability of surfactant ( fatal if deficient )

SP-D Primary Role

Host defense and regulation of inflammation

A 29- week gestation neonate is experiencing respiratory distress: grunting, nasal flaring,tachypnea and intercostal retractions. CXR shows diffuse ground glass opacities and air bronchograms.

What condition is likely based on clinical and radiographic findings?

RDS

A 29- week gestation neonate is experiencing respiratory distress: grunting, nasal flaring,tachypnea and intercostal retractions. CXR shows diffuse ground glass opacities and air bronchograms.

Would you administer surfactant prophylactically or a rescue therapy?

Rescue therapy

A 29- week gestation neonate is experiencing respiratory distress: grunting, nasal flaring,tachypnea and intercostal retractions. CXR shows diffuse ground glass opacities and air bronchograms.

Which delivery method would be appropriate in this scenario? justify your choice

• mechanically ventilate and administer surfactant therapy

• LISA- less invasive surfactant administration

What is the formula for LaPlace’s Law and how does surfactant affect it

P= 2xST divided by radius

• reduces surface tension and prevents the alveoli from collapsing

What percent of phosphatidylcholine is made up of DPPC?

40-45%

What are the four types of surfactant preparations?

• natural ( animal derived )

• synthetic surfactants ( protein free)

• synthetic surfactants ( protein containing )

• combination or investigational surfacatants )

What surfactant proteins contribute to host defense?

SP-D

What L:S ratio and PG result indicates fetal lung maturity?

> or equal to 2:1

if PG is present= maturity

According to LaPlace’s Law, which alveoli are at greater risk of collapse in the absence of surfactant?

Smaller alveoli due to increased surface tension

Which component of endogenous surfactant makes up the largest proportion of its phospholipid content?

Dipalmitoyl phosphatidylcholine ( DPPC )

Which of the following is a rescue indication for surfactant replacement therapy?

Preterm infant intubated with clinical signs of RDS

A positive result on the foam stability test indicates which of the following?

Stable foam formation despite > 48% ethanol

What does the L:S ratio measure?

Lecithin/Sphinogomyelin ratio

• fetal lung maturtiy

What L:S Ratio result indicate maturity?

> 2:1

greater than or equal to 2

What sample type is required for the L:S ratio?

Amniotic fluid

What does PG measure?

Presence of phosphatidylglycerol

What result indicates maturity in PG?

When PG is present

What sample type is required for a PG test?

Amniotic fluid

What does a Foam Stability test measure?

ability of surfactant to from stable foam

What result indicates maturity in a foam stability test?

stable bub bles at > 48% ethanol

What sample type is required in a foam stability test?

amniotic fluid

Inhaled Nitric oxide mechanism

Pulmonary vasodilation in ventilated alveoli

Inhaled nitric oxide clinical use

persistent pulmonary hypertension of the newborn ( PPHN )

Inhaled nitric oxide key risks

Methemoglobinemia NO2 toxicity