12-phase flow (10)

1. 1FRAME
   HTN emergency in kidney transplant — multifactorial etiology (CNI vasoconstriction + volume + acute rejection + TRAS + native disease recurrence + steroid burst). Drug profile pivots: nicardipine first-line (renal-friendly DHP-CCB; minimal CYP3A4); AVOID nitroprusside if eGFR <30 (cyanide accumulation); AVOID ACEi/ARB if rising Cr (worsens AKI); AVOID diltiazem/verapamil long-term (CYP3A4 — increases CNI levels); statin interactions matter (pravastatin/fluvastatin/rosuvastatin preferred). Critical workup: STAT renal Doppler for TRAS + CMV/BK PCR + DSA for rejection + biopsy if Cr rising. Route to parent engine for shared HTN-emergency arc + nephrology + transplant team for graft management.
   inputs: sbp, dbp, transplant_date_and_donor_type, creatinine, tacrolimus_or_cyclosporine_trough_level
   advance: transplant context + CNI level + Cr trajectory characterized
2. 2ENTRY
   Recognize transplant + severe HTN; STAT renal Doppler ultrasound + transplant team activation; do NOT delay BP lowering for full workup
   inputs: age, sbp
   advance: IV access + BP lowering initiated + transplant team notified
3. 3CONTEXT
   Transplant date + donor type (DCD vs DBD vs living), induction agent, current IS regimen (CNI + MMF + prednisone), recent dose changes, prophylaxis completion (CMV, PJP), DSA history, prior rejection episodes, native disease (relevant for recurrence), recent infections, dietary salt, missed doses, OTC NSAID use
   inputs: transplant_date_and_donor_type, immunosuppressant_regimen
   advance: context complete with IS regimen + interaction screen
4. 4RED_FLAGS
   Concurrent stroke (HTN-driven), pulmonary edema (volume overload + LV dysfunction), severe AKI (anuria, K elevation), acute rejection signs (graft tenderness, fever, oliguria), TRAS bruit, drug-interaction missed (recent macrolide / azole / diltiazem)
   inputs: sbp, creatinine
   actions: htn_emergency
   advance: RED flags screened + acute rejection vs TRAS vs CNI toxicity differential framed
5. 5INITIAL_WORKUP
   CMP + Mg + uric acid + LDH; CBC; CNI trough (tacrolimus or cyclosporine); CMV PCR; UA + UPCR (proteinuria suggests recurrence or rejection); BMP for K/HCO3; STAT renal Doppler ultrasound (TRAS + RI assessment); ECG (LVH); CXR (volume overload); β-hCG if reproductive-age
   inputs: creatinine, tacrolimus_or_cyclosporine_trough_level, cmv_pcr, renal_doppler_ultrasound
   actions: panel.cardiac, panel.renal
   advance: workup documented + Doppler reviewed + CNI level returned
6. 6BRANCHING_WORKUP
   BK PCR if CNI low or recent change; donor-specific antibodies if AMR suspected; CTA renal arteries if Doppler suggests TRAS (RI >0.7 or velocity ratio elevated; CTA preferred over MRA for eGFR <30 due to NSF); renal biopsy if rising Cr + clinical suspicion of rejection (Banff 2019 grading); HRCT chest if PJP or CMV pneumonitis suspected
   inputs: bk_pcr, donor_specific_antibodies, cross_sectional_for_TRAS_if_suspected, renal_biopsy_if_rejection_suspected
   advance: TRAS confirmed/excluded + rejection biopsy decision made + DSA/CMV/BK results integrated
7. 7TREATMENT
   NICARDIPINE IV first-line (renal-friendly DHP-CCB; minimal CYP3A4 effect on tacrolimus; predictable titration). Goal: SBP <140-160 within 6-12 h (gentler than non-transplant given graft autoregulation impairment + AKI risk). LABETALOL second-line if tachycardia. AVOID nitroprusside if eGFR <30 (cyanide; thiocyanate accumulation; common in transplant given graft dysfunction). AVOID ACEi/ARB acutely if rising Cr (worsens AKI by efferent vasodilation; restart later once stable). AVOID diltiazem/verapamil long-term as monotherapy (increases tacrolimus 30-50% via CYP3A4 — though sometimes used INTENTIONALLY to reduce CNI dose). For acute rejection: STAT pulse steroid (methylprednisolone 500-1000 mg IV × 3-5 days) + ATG if Banff IIA-IIB; for AMR add plasmapheresis + IVIG ± rituximab. For TRAS: percutaneous angioplasty ± stenting (gold standard if anatomy suitable). For CNI toxicity: dose reduction guided by trough level. For BK nephropathy: REDUCE immunosuppression (paradoxical compared to rejection).
   inputs: sbp, dbp, creatinine, tacrolimus_or_cyclosporine_trough_level
   advance: BP at target + etiology-specific intervention initiated + nephrology + transplant teams co-managing
8. 8DISPOSITION
   ICU mandatory for q5-15 min BP titration + a-line; nephrology + transplant team consults; interventional radiology if TRAS angioplasty; transplant surgery if biopsy / explant decision
   advance: ICU bed + nephrology + transplant + IR (if applicable) consults booked
9. 9MONITORING
   A-line + q5-15 min BP; q4-6h BMP for K + Cr (Cr trajectory drives ACEi/ARB restart timing); q12h CNI trough during titration; serial CBC; UOP + dialysis access if oliguric; daily Doppler if TRAS; serial DSA if AMR treatment; serial CMV/BK PCR if viral driver
   inputs: sbp, creatinine, tacrolimus_or_cyclosporine_trough_level
   actions: panel.renal
   advance: BP at target + Cr stable or improving + viral PCR trending down + DSA decreasing
10. 10FOLLOWUP
    Transition to oral 4-tier ladder once stable × 12-24 h (amlodipine + thiazide-like + ACEi/ARB once Cr stable + BB if cardiac indication); long-term BP target <130/80 per KDIGO 2020; lifelong CNI level monitoring (q1-3 mo); annual cardiac surveillance (CV is leading cause of death in transplant); CMV/BK PCR per local protocol; DSA monitoring annually; vaccination updates (avoid live); cancer surveillance (skin, PTLD)
    advance: oral regimen stable + nephrology + transplant + cardiology surveillance plan in place