12-phase flow (12)

1. 1FRAME
   Frame by gestational age cohort (≥35 0/7 wk term per Puopolo 30455342 vs ≤34 6/7 wk preterm per Puopolo 30455344), postnatal age in hours (EOS < 72 h), and birth weight (per-kg dosing).
   inputs: gestational_age_weeks, birthweight_grams, postnatal_age_hours
   advance: Cohort + age + weight captured; framework selected
2. 2ENTRY
   Identify trigger: clinical signs (respiratory distress, temperature instability, lethargy, poor feeding) OR maternal risk factors (chorioamnionitis, GBS-positive with inadequate IAP, preterm, PROM > 18 h) OR positive screening per Kaiser EOS calculator (Kuzniewicz 2017 PMID 28241253).
   inputs: maternal_gbs_status_and_iap_adequacy, maternal_intrapartum_fever_or_chorioamnionitis, duration_of_rom_hours
   advance: EOS suspicion documented and classified (clinical sepsis vs risk-only)
3. 3CONTEXT
   Maternal GBS status + IAP adequacy + intrapartum fever / chorioamnionitis + ROM duration + maternal HSV / hepatitis B / HIV / VDRL status; infant exam (perfusion, tone, fontanelle, rashes).
   inputs: maternal_gbs_status_and_iap_adequacy, maternal_intrapartum_fever_or_chorioamnionitis, duration_of_rom_hours, maternal_herpes_lesions_or_history, hr_neonate, rr_neonate, spo2_pre_and_post_ductal
   advance: Maternal-infant risk profile + infant exam documented
4. 4RED_FLAGS
   Hemodynamic instability (hypotension by GA threshold, capillary refill > 3 s, mottling, lactate > 4) → ICU + fluid resuscitation + vasoactive. Respiratory failure / apnea + bradycardia → intubation. CNS features (seizure, bulging fontanelle, meningismus) → LP + meningitic-dose antibiotics. Active maternal HSV lesions or vesicular rash on infant → empirical acyclovir.
   inputs: temperature_neonate, sbp_neonate, maternal_herpes_lesions_or_history, cns_signs_seizure_bulging_fontanelle
   actions: protocol.septic_shock
   advance: Red flags actioned; empiric antibiotics within 60 min
5. 5INITIAL_WORKUP
   Blood culture (≥ 1 mL pre-antibiotic); CBC with diff + I:T ratio; CRP baseline; glucose; lactate; CXR; ampicillin + gentamicin within 1 h. Cultures BEFORE antibiotics if possible without delaying treatment past 60 min (Puopolo 2018).
   inputs: cbc_with_diff_neonate, blood_culture_pre_antibiotic, crp_serial, glucose_neonate, cxr_neonate
   actions: panel.cbc, panel.inflammation, panel.abg
   advance: Cultures sent; first-dose antibiotics in; CXR obtained
6. 6BRANCHING_WORKUP
   LP if culture-positive sepsis, CNS features, persistent positive blood cultures, or culture-negative but high clinical suspicion (Puopolo 2018). HSV PCR (blood, CSF, surface swabs) if maternal HSV or vesicular rash. UA / urine culture is low-yield in EOS (< 72 h) but appropriate for late-onset (> 72 h) — out of scope for this acute EOS engine.
   inputs: csf_studies_if_LP, lactate_neonate
   actions: workup.bacterial_meningitis
   advance: Source-directed workup complete or empirically covered
7. 7DIFFERENTIAL
   EOS vs RDS (no maternal sepsis risk factors; classic preterm ground-glass CXR — route to neonatal.respiratory-distress-syndrome.v1). EOS vs PPHN (pre-/post-ductal gradient; echo). EOS vs CHD (congenital cyanotic vs ductal-dependent — echo + hyperoxia test). EOS vs HIE (history of asphyxia / acidosis — route to neonatal.hypoxic-ischemic-encephalopathy.v1). EOS vs metabolic (inborn errors with shock-like presentation — acidosis + hyperammonemia + lactate).
   advance: Mimics excluded or co-managed; empiric antibiotics continued
8. 8RISK_STRATIFICATION
   Kaiser EOS calculator (Kuzniewicz 2017 PMID 28241253) for ≥35 wk asymptomatic infants — combines maternal factors (chorioamnionitis, GBS, IAP, ROM, fever) with infant clinical status to drive observation-vs-cultures-vs-antibiotics. Term-symptomatic + preterm → empiric antibiotics per Puopolo (no calculator branch). Calculator id `calc.kaiser_eos_calculator` not yet registered in clinical-tools-registry — rendered narratively this pass.
   inputs: gestational_age_weeks
   advance: Stratification + decision (observe / culture / antibiotics) documented
9. 9TREATMENT
   Empiric ampicillin + gentamicin within 60 min. Acyclovir added if HSV concern (max 60 mg/kg/day). Pathogen-directed narrowing once culture + susceptibilities back at 36-72 h. AVOID ceftriaxone in < 28 d (bilirubin displacement); use cefotaxime if a cephalosporin is needed. Supportive: IV maintenance fluids, glucose control, ventilation as needed, vasoactive per septic-shock protocol.
   inputs: birthweight_grams, postnatal_age_hours
   advance: Empiric regimen in; supportive care titrated
10. 10DISPOSITION
    Symptomatic / preterm / culture-positive → NICU (icu). Asymptomatic / term / culture-negative observation per Kaiser EOS calculator → inpatient (well-baby / mother-baby unit) with serial exams. Stable post-EOS rule-out (48-72 h negative culture + improving CRP + reassuring exam) → discharge with peds follow-up 24-48 h.
    inputs: gestational_age_weeks
    advance: Level of care assigned
11. 11MONITORING
    Continuous cardiorespiratory monitoring + SpO₂ + temperature. CBC + CRP at 24 + 48 h. Blood culture follow-up at 36-48 h. Gentamicin trough before 3rd dose (target < 2 mcg/mL). Repeat LP at 48 h if culture-positive meningitis. Glucose q4-6h. Stop antibiotics at 36-48 h if culture-negative + reassuring infant + normalized CRP / CBC per Puopolo 2018 stewardship.
    inputs: cbc_with_diff_neonate, crp_serial, blood_culture_pre_antibiotic
    actions: panel.cbc, panel.inflammation
    advance: Stewardship + de-escalation per culture results
12. 12FOLLOWUP
    Pediatric follow-up within 24-48 h of discharge for high-risk; 1-week visit for all. Hearing screen (AABR) — sensorineural hearing loss is a sequela of bacterial meningitis. Neurodevelopmental peds at 6-12 mo for culture-positive meningitis or septic-shock survivors (Bayley III / ASQ-3). Immunization catch-up per ACIP schedule.
    advance: Outpatient plan + hearing screen + neurodev follow-up scheduled