Neonatology

Neonatology Indian Medical PG Question 1: In a preterm baby with respiratory distress syndrome, which of the following lipids would be deficient?

• A. Cardiolipin
• B. Sphingomyelin
• C. Phosphatidylinositol
• D. Lecithin (Correct Answer)

Neonatology Explanation: ***Lecithin*** - **Lecithin** (also known as **phosphatidylcholine**) is the primary component of **surfactant** in the lungs, which reduces surface tension and prevents alveolar collapse. - In **preterm babies**, insufficient production of lecithin due to immature lung development leads to **respiratory distress syndrome (RDS)**. *Cardiolipin* - **Cardiolipin** is a major phospholipid found in the **inner mitochondrial membrane**, crucial for oxidative phosphorylation. - Deficiency is associated with mitochondrial disorders like **Barth syndrome**, not primary respiratory distress. *Sphingomyelin* - **Sphingomyelin** is a significant component of **cell membranes** and **myelin sheaths**, important for nerve insulation. - While present in the lungs, its primary role is not in surface tension reduction, and its deficiency is not directly linked to RDS. *Phosphatidylinositol* - **Phosphatidylinositol** is a precursor for various **signaling molecules** and plays a role in cell membrane structure. - While involved in cellular processes, it is not the critical surfactant component whose deficiency causes RDS.

Neonatology Indian Medical PG Question 2: According to neonatal resuscitation protocol, how much oxygen to give in a term neonate with apnea and bradycardia initially?

• A. 100%
• B. 21% (Correct Answer)
• C. 50%
• D. 30%

Neonatology Explanation: ***21%*** - According to **NRP (Neonatal Resuscitation Program) 2020 guidelines**, for **term neonates (≥35 weeks gestation)** requiring resuscitation, the initial recommendation is to use **room air (21% oxygen)** to minimize the risk of hyperoxia and oxidative injury. - Multiple randomized controlled trials have demonstrated that room air is as effective as 100% oxygen for initial resuscitation. - Supplemental oxygen is only added if **oxygen saturation targets** are not met despite adequate ventilation, and should be titrated using **pulse oximetry**. *30%* - This concentration is **higher than room air** and is not the initial recommendation for term neonates needing resuscitation. - Starting with a higher oxygen concentration can lead to **oxidative stress** without immediate benefit. - Higher initial concentrations (21-30%) are reserved for **preterm neonates (<35 weeks)**. *100%* - Administering **100% oxygen** can be harmful to a neonate, potentially causing **oxidative injury** to developing organs, including the lungs, brain, and retina. - This was the old practice but has been **discontinued** based on evidence showing increased mortality and morbidity. - High concentrations are no longer recommended even in severe cases; oxygen should be titrated to saturation targets. *50%* - While lower than 100%, 50% oxygen is still **not the initial recommended concentration** for term neonates in resuscitation protocols. - The goal is to start with **21% oxygen** and gradually increase based on **pulse oximetry monitoring** and target saturation ranges if 21% is insufficient.

Neonatology Indian Medical PG Question 3: A preterm infant with poor respiration at birth starts throwing seizures at 10 hours after birth. Antiepileptic of choice shall be:

• A. Phenobarbitone (Correct Answer)
• B. Lorazepam
• C. Levetiracetam
• D. Phenytoin

Neonatology Explanation: ***Phenobarbitone*** - **Phenobarbitone** is the **first-line antiepileptic drug** recommended for neonatal seizures due to its established efficacy and safety profile in this population. - It acts primarily by **potentiating GABAA receptor-mediated chloride currents**, leading to central nervous system depression and seizure control. *Lorazepam* - While **benzodiazepines** like lorazepam can be used for acute seizure cessation, especially status epilepticus, they are generally **not the first-line choice for maintenance therapy** due to potential sedation and respiratory depression in neonates. - Its short duration of action and risk of rebound seizures make it less suitable as a sole agent for ongoing seizure control. *Levetiracetam* - **Levetiracetam** is an increasingly common antiepileptic in neonates, but its long-term efficacy and safety, particularly regarding neurodevelopmental outcomes, are **still under investigation** compared to phenobarbitone. - While it may be used as a second-line agent or in specific situations, it is **not universally considered the first-line drug of choice** for neonatal seizures. *Phenytoin* - **Phenytoin** is typically considered a **second-line or third-line antiepileptic** for neonatal seizures, primarily used if phenobarbitone is ineffective. - Its use is limited by potential side effects such as **cardiac arrhythmias, hypotension, and infiltration at the injection site**, which can be particularly concerning in premature infants.

Neonatology Indian Medical PG Question 4: Which of the following is the main factor for the ductus arteriosus closure postnatally?

• A. Increase in partial pressure of oxygen (PaO2) (Correct Answer)
• B. Elevated levels of circulating prostaglandins
• C. Reduction in pulmonary vascular resistance
• D. Postnatal increase in systemic vascular resistance

Neonatology Explanation: ***Increase in partial pressure of oxygen (PaO2)*** - The **increase in PaO2** after birth causes a profound relaxation of the **pulmonary arterioles** and constriction of the **ductus arteriosus**. - This is the most crucial physiological change, leading to the **functional closure** of the ductus within hours of birth. *Postnatal increase in systemic vascular resistance* - While systemic vascular resistance (SVR) does increase postnatally as the **placental circulation** ceases, it is not the primary direct cause of ductus arteriosus closure. - An increased SVR contributes to the **pressure gradient** changes in the heart, but the oxygen-mediated constriction is more direct and powerful for the ductus itself. *Elevated levels of circulating prostaglandins* - **Prostaglandins**, particularly PGE2, are responsible for **maintaining the patency** of the ductus arteriosus *in utero*. - After birth, the **decrease in prostaglandin levels** (due to lung metabolism and removal of the placenta) is essential for closure, but elevated levels would actually keep it open. *Reduction in pulmonary vascular resistance* - A reduction in **pulmonary vascular resistance (PVR)** is indeed a significant postnatal change, allowing for increased pulmonary blood flow. - While this change alters blood flow dynamics, the direct cause of ductus arteriosus constriction is the **increased PaO2**, not solely the fall in PVR.

Neonatology Indian Medical PG Question 5: The fetal well-being can be assessed by all of the following, except

• A. non-stress test
• B. ultrasound
• C. contraction stress test
• D. Kleihauer-Betke test (Correct Answer)

Neonatology Explanation: ***Kleihauer-Betke test*** - The **Kleihauer-Betke test** is used to quantify the amount of **fetal hemoglobin** that has entered the maternal circulation, typically in cases of **fetomaternal hemorrhage**. - It does assess fetal red blood cells in maternal circulation but does not directly assess current fetal well-being in terms of **cardiac activity**, **movement**, or **oxygenation**. *non-stress test* - The **non-stress test (NST)** monitors **fetal heart rate (FHR)** accelerations in response to fetal movement as an indicator of adequate **fetal oxygenation** and **autonomic nervous system function**. - A **reactive NST** with appropriate accelerations is considered a sign of **fetal well-being**. *ultrasound* - **Ultrasound** is a versatile tool for assessing fetal well-being, providing information on **fetal growth**, **anatomy**, **amniotic fluid volume**, and **biophysical profile (BPP)**. - The BPP, which includes ultrasound observations of **fetal breathing**, **movement**, **muscle tone**, and **amniotic fluid volume**, along with an **NST**, offers a comprehensive assessment of fetal status. *contraction stress test* - The **contraction stress test (CST)** evaluates the response of the **fetal heart rate** to uterine contractions, which temporarily reduce placental blood flow. - A **negative CST** (no late decelerations) indicates good **fetal oxygen reserve** and is a reliable sign of **fetal well-being**.

Neonatology Flashcard 1 of 5

Question: During neonatal resuscitation, the _____ is suctioned first and then the nares

Answer: mouth

Neonatology Flashcard 2 of 5

Question: Which route is preferred for epinephrine administration for neonatal resuscitation?_____

Answer: IV>ETT

Neonatology Flashcard 3 of 5

Question: MC cause of neonatal death is _____

Answer: prematurity

Extra Information: 

Neonatology Flashcard 4 of 5

Question: _____ is the gold standard for diagnosis and quantification of seizures in neonates

Answer: Video-EEG

Neonatology Flashcard 5 of 5

Question: If the newborn is of term gestation, breathing/crying and has good muscle tone, the next step is to provide _____

Answer: routine newborn care