12-phase flow (12)

1. 1FRAME
   Frame eligibility per Papile AAP 2014: GA ≥36 wk, BW ≥1800 g, postnatal age ≤6 h, AND (acidosis with cord/first-hour pH <7.0 or BE ≤ -16) OR (acute perinatal event with continuing need for resuscitation), AND moderate-to-severe encephalopathy (Sarnat 2/3) OR abnormal aEEG.
   inputs: gestational_age_weeks, birthweight_grams, postnatal_age_hours, cord_blood_gas_pH_BE, apgar_score_at_5_and_10_min
   advance: Cooling eligibility confirmed or excluded (clear pathway)
2. 2ENTRY
   Identify trigger: sentinel event at delivery (cord prolapse, abruption, uterine rupture, shoulder dystocia delay), persistent low Apgar (≤5 at 10 min), need for prolonged resuscitation, abnormal exam (Sarnat 2/3), or neonatal seizure.
   inputs: apgar_score_at_5_and_10_min, sarnat_stage_serial
   advance: HIE entry trigger documented
3. 3CONTEXT
   Maternal-fetal history (sentinel event, abruption, cord, dystocia), birth history (delivery mode, resuscitation duration, intubation, chest compressions, epinephrine), cord gas pH + BE.
   inputs: cord_blood_gas_pH_BE, apgar_score_at_5_and_10_min, sarnat_stage_serial
   advance: Birth context + acidosis evidence documented
4. 4RED_FLAGS
   Sarnat stage 3 (deep stupor / coma + flaccid + absent reflexes + seizures) → emergent cooling. Refractory seizures → phenobarbital load + levetiracetam. Hyperthermia (any T > 37.5 °C in HIE infant) is HARMFUL → active cooling. Multi-organ failure (AKI, hepatic, coagulopathy, cardiac) → ICU + supportive care. Do NOT delay cooling for transport.
   inputs: core_temperature, sarnat_stage_serial
   advance: Red flags addressed; cooling initiated within 6 h
5. 5INITIAL_WORKUP
   aEEG / EEG continuous monitoring. ABG + CBC + coag + glucose + metabolic panel + lactate. Cranial US baseline. IV access (UVC preferred). Esophageal or rectal temperature probe for cooling. Family discussion + consent.
   inputs: abg_or_cbg_neonate, cbc_with_diff_neonate, coag_panel_neonate, glucose_neonate, metabolic_panel_neonate, lactate_neonate, aEEG_continuous_monitoring
   actions: panel.cbc, panel.abg, panel.coag, panel.renal
   advance: Labs + monitoring in place; cooling initiated
6. 6BRANCHING_WORKUP
   Cranial US for IVH baseline. MRI at 4-7 d post-cooling for prognostic anchor. Sepsis workup (cultures + LP) if differential includes meningitis. Echo for cardiac dysfunction (HIE often has myocardial stunning). Renal function trending (AKI common). Liver function trending (hepatic injury common).
   inputs: mri_brain_post_cooling, cranial_ultrasound_baseline
   advance: Source-directed branches resolved or empirically covered
7. 7DIFFERENTIAL
   HIE vs neonatal sepsis with shock (cultures + WBC + maternal risk; route to neonatal.early-onset-sepsis.v1). HIE vs metabolic / inborn error (acidosis + hyperammonemia + organic acid panel). HIE vs stroke (focal deficit, MRI). HIE vs congenital brain malformation (US / MRI). HIE vs neuromuscular (myopathy / SMA / mitochondrial — bilateral floppy with relatively preserved consciousness).
   advance: Mimics excluded
8. 8RISK_STRATIFICATION
   Sarnat stage 1 (mild, no cooling), Sarnat 2 (moderate, cooling indicated), Sarnat 3 (severe, cooling indicated, worse prognosis). aEEG pattern (burst suppression + continuous low voltage + flat → worse). MRI pattern at 4-7 d (basal ganglia / thalamus + watershed + global → worse prognosis). Multi-organ involvement severity. Calculator id `calc.sarnat_stage` not yet registered in clinical-tools-registry — rendered narratively.
   inputs: sarnat_stage_serial, aEEG_continuous_monitoring
   advance: Severity tier assigned + prognosis discussion with family
9. 9TREATMENT
   THERAPEUTIC HYPOTHERMIA — whole-body (Shankaran NICHD NEJM 2005 PMID 16221780; Azzopardi TOBY NEJM 2009 PMID 19797281) or selective head cooling (Gluckman CoolCap Lancet 2005 PMID 15721471). Target 33.5 °C × 72 h, then slow rewarming 0.5 °C/h over 6-8 h. Seizure control with phenobarbital 20 mg/kg load (max cumulative 40 mg/kg); levetiracetam 20-60 mg/kg adjunct. Comfort with morphine 0.05-0.1 mg/kg q4h PRN during cooling. AVOID hyperthermia. Tight glucose 70-150 mg/dL. Supportive: ventilation, vasoactive, AKI management.
   inputs: birthweight_grams, core_temperature
   advance: Cooling initiated; seizure control achieved; supportive care titrated
10. 10DISPOSITION
    NICU (icu) — cooling capable center; transfer initiated immediately if delivered outside cooling center (do NOT delay cooling for transfer; passive cooling at referring center). Post-rewarming → continued NICU monitoring × 24-48 h. Step-down to special-care nursery when off ventilator + tolerating feeds + neurologically stable.
    inputs: gestational_age_weeks
    advance: Level of care assigned; transfer arrangements complete if needed
11. 11MONITORING
    Continuous aEEG / EEG × 72 h cooling + 24 h post-rewarming. Continuous SpO₂ + cardiorespiratory + invasive BP + core temperature. Serial neuro exam + Sarnat staging. Labs: ABG + lactate q4-6h; CBC + coag + electrolytes + glucose + LFT + renal q6-12h. Phenobarbital level if breakthrough seizures. MRI at 4-7 d post-cooling.
    inputs: core_temperature, aEEG_continuous_monitoring, mri_brain_post_cooling
    actions: panel.cbc, panel.coag, panel.renal, panel.abg
    advance: Cooling complete + rewarming complete + MRI obtained + family prognostic discussion
12. 12FOLLOWUP
    Neurology + developmental peds follow-up at 3 + 6 + 12 + 18-24 mo (Bayley III). Hearing screen (AABR) + audiology at 3 mo. Ophthalmology if cortical visual impairment suspected. PT / OT / speech / feeding therapy as needed. Anticonvulsant taper / continuation per epilepsy status. Family / parental support + grief counseling for severe outcomes.
    advance: Long-term follow-up plan documented; family education complete