Diagnosis: Hypoxic-Ischemic Encephalopathy (HIE) — Severe (Sarnat Stage III)

Imaging Findings (from the reports)

• Increased periventricular echogenicity (more on left side)
• Ventricular system collapsed/squashed
• No SOL, no midline shift, no hemorrhage
• Conclusion: Increased periventricular echogenicity → HIE? with squashed ventricular chain

• Hyperdense right and left transverse sign, CT density ~47 HU
• Lateral ventricular chain effaced, appear like slits — HIE???
• Effacement of sulci and gyri
• No SOL, no midline shift
• Brain stem, cerebellum, and basal ganglia appear normal; bilateral CP angles clear
• Impression:
  • Effaced lateral ventricles and sulci/gyri → HIE
  • Hyperdense right and left transverse sinuses with blood density — raised suspicion for SAH / AV thrombosis (CSVT)
  • MHV/MRI scan recommended

Clinical Correlation

Sarnat Staging — Where Does This Baby Fit?

Management

1. Immediate Stabilization

• Airway: Intubate if not already done — gasping is not adequate ventilation
• Maintain normoglycemia (glucose 45–100 mg/dL)
• Correct metabolic acidosis, electrolyte disturbances
• Avoid hyperthermia (worsens injury), hyperoxia, hypo/hypercapnia

2. Therapeutic Hypothermia (TH) — Critical Window

• Criteria: Gestational age >35 weeks + moderate/severe HIE
• Target temperature: 33–34°C (whole body) for 72 hours
• Must be initiated within 6 hours of birth
• Number needed to treat (NNT) = 7 to prevent one death or severe impairment
• If >6 hours have already elapsed since birth, TH is not recommended — this is crucial given that this baby appears to be day 5 at the time of imaging

⚠️ Important: If this baby is day 5 at time of imaging (USG report dated Day 5, CT report dated Day 5), the 6-hour window for therapeutic hypothermia has long passed. TH would no longer be indicated.

3. Seizure Management

• Continuous EEG/aEEG monitoring
• First line: Phenobarbital IV (20 mg/kg loading dose)
• Second line: Levetiracetam, phenytoin/fosphenytoin
• Treat clinical and subclinical seizures aggressively

4. MRI/MRV Brain — Urgent

• Recommended by the CT report itself
• To confirm pattern of HIE injury (basal ganglia-thalamus vs. watershed pattern)
• To rule out/confirm CSVT (hyperdense transverse sinuses on CT)
• Ideally done after hypothermia completion (day 3–4) when DWI abnormalities are most apparent

5. If CSVT Confirmed on MRI/MRV

• Anticoagulation (LMWH) is considered if no major hemorrhage
• Neurology/hematology consult

6. Supportive Care

• Avoid hypotension (maintain cerebral perfusion pressure)
• Restrict fluids to ~60 mL/kg/day initially (cerebral edema)
• Maintain normocapnia (PaCO₂ 45–55 mmHg)
• Monitor for SIADH, renal failure, hepatic dysfunction, coagulopathy (multi-organ dysfunction from asphyxia)
• Nutritional support (TPN if enteral feeds not tolerated)

7. Adjunct Therapies (Under Investigation)

• Erythropoietin (EPO) — neuroprotective, studied but not yet standard of care (PMID 38171084)
• Melatonin, allopurinol — investigational

8. Family Counseling

• Prognosis with severe HIE (Sarnat III) is extremely guarded: 100% poor outcome rate (death or severe disability)
• Outcomes include spastic quadriparesis, intellectual disability, cortical visual impairment, epilepsy
• Early palliative care discussion may be appropriate

Summary

• Primary diagnosis: Severe HIE (Sarnat Stage III)
• Secondary concern: CSVT (hyperdense transverse sinuses on CT) — needs MRI/MRV urgently