Growing Preterm and Low Birth Weight Infant - High-Yield Viva Questions
| Question | Answer / Practical Pearls |
|---|---|
| How do you define Chronological Age, Gestational Age, Post-Menstrual Age, and Corrected Age? | • Gestational Age (GA): Time elapsed between the first day of the last normal menstrual period (LMP) and the day of delivery, expressed in completed weeks. • Chronological Age: Time elapsed since birth, in days, weeks, or months. • Post-Menstrual Age (PMA): Gestational age at birth plus chronological age in weeks ($GA + \text{Postnatal weeks}$). Used in NICU to assess physiological maturity (e.g., suck-swallow coordination, apnea resolution). • Corrected Age (Post-Term Age): Chronological age reduced by the number of weeks born before 40 completed weeks ($\text{Corrected Age} = \text{Chronological Age} - [40 - GA]$). Used for plotting growth and evaluating developmental milestones up to 2 years of age. VIVA TRAP: Vaccinations are given strictly by CHRONOLOGICAL AGE, never corrected age! |
| What are the physiological components and documented benefits of Kangaroo Mother Care (KMC)? | • Components: Continuous skin-to-skin contact (SSC) in the kangaroo position (upright between maternal breasts, head turned to side, neck slightly extended, hips in frog-leg abduction) + exclusive breastfeeding/EBM + early discharge and close follow-up. • Mortality Benefit: Cochrane reviews demonstrate a $40\%$ reduction in mortality among stabilized low-birth-weight infants. • Morbidity Reductions: $65\%$ reduction in nosocomial sepsis/severe infections, $70\%$ reduction in hypothermia, $50\%$ reduction in severe respiratory illness, faster daily weight gain ($+2-5\text{ g/kg/day}$), higher rates of exclusive breastfeeding at 1-4 months, and earlier discharge. • Minimum Duration: Intermittent KMC should last at least 60 minutes per session (to avoid sleep-wake disruption); total daily duration should be as long as possible (ideally $\ge 12-16\text{ hours/day}$). |
| What are the criteria and timing for Retinopathy of Prematurity (ROP) screening in India? | • NNF / RBSK Indian Screening Criteria: 1. Birth weight $\le 1750\text{ grams}$ AND/OR Gestational age $\le 34\text{ completed weeks}$. 2. Selected infants $34-36\text{ weeks}$ or $1750-2000\text{ g}$ with unstable clinical course (prolonged oxygen, mechanical ventilation, sepsis, blood transfusions). • Timing ('Rule of 30 Days'): First examination within 4 weeks of birth (30 days), OR at 31-32 weeks PMA, whichever is EARLIER. • High-Risk Preterms (<28 weeks or <1000g): Screen early at 2 to 3 weeks of postnatal age. VIVA TRAP: 'Plus Disease' indicates active, virulent disease requiring urgent treatment within 48-72 hours (Laser indirect photocoagulation or Intravitreal Anti-VEGF)! |
| How is Metabolic Bone Disease of Prematurity (Osteopenia of Prematurity) screened and managed? | • Pathophysiology: $80\%$ of fetal bone mineral accretion (Calcium $100-120\text{ mg/kg/d}$, Phosphorus $50-65\text{ mg/kg/d}$) occurs in the 3rd trimester; truncated by preterm birth. • Biochemical Screening at 4 to 6 Weeks Postnatal Age: - Serum Alkaline Phosphatase (ALP): $>800-900\text{ IU/L}$ indicates active demineralization. - Serum Phosphorus: $<4.5\text{ mg/dL}$ indicates severe depletion. - Tubular Resorption of Phosphate (TRP): $>95\%$ confirms renal phosphate conservation secondary to total body phosphate deficit. • Management: Multi-nutrient Human Milk Fortifier (HMF), oral Calcium ($150-200\text{ mg/kg/d}$), Phosphorus ($75-100\text{ mg/kg/d}$), and Vitamin D3 ($800-1000\text{ IU/day}$). |
| What are the definitive discharge criteria for a growing preterm infant? | 1. Hemodynamically stable; off oxygen and apnea-free for $\ge 48-72\text{ hours}$. 2. Consistent daily weight gain of $\ge 15-20\text{ g/kg/day}$ for 3 consecutive days. 3. Maintaining normal body temperature ($36.5-37.5^\circ\text{C}$) in room air without KMC for at least 4-6 hours. 4. Taking all feeds successfully by direct breast or paladai/cup without aspiration or fatigue. 5. Weight has reached $\ge 1.6-1.8\text{ kg}$ (depending on institutional protocol and home environment). 6. ROP and hearing screening scheduled or completed. 7. Primary caregiver is confident in KMC, paladai feeding, thermal care, and danger sign identification. |