12-phase flow (10)

1. 1FRAME
   Stimulant withdrawal HTN crisis = abrupt cessation of chronic stimulant use → autonomic instability + rebound NE release (recovery faster than receptor upregulation reverses) → HTN + tachy + diaphoresis + tremor + agitation overlap with depression ("crash") 6-72 h post cessation. Pharmacology pivot: BENZODIAZEPINE FIRST for sympatholysis + agitation/anxiety; nicardipine IV for HTN; phentolamine for severe; CCB acceptable; AVOID isolated β-blocker monotherapy (unopposed alpha principle); CONSIDER stimulant restart if clearly iatrogenic (held during OR, rehab admission) or arrange gradual taper if planned discontinuation. Distinguish from active intoxication crisis (active-use toxidrome) and clonidine withdrawal (different mechanism). Route to parent engine for shared HTN-emergency arc; this dossier owns the withdrawal-specific pharmacology + SUD treatment + psychiatric care.
   inputs: sbp, dbp, heart_rate, stimulant_use_history, cessation_timing_and_reason
   advance: stimulant withdrawal etiology confirmed by history + cessation timing 6-72 h
2. 2ENTRY
   Recognize withdrawal toxidrome (HTN + tachy + diaphoresis + tremor + agitation + depression "crash" 6-72 h post cessation); ECG within 10 min if chest pain; benzo-first sympatholysis; psychiatric assessment for suicide risk
   inputs: age, sbp, agitation_and_tremor_assessment, depression_and_suicide_screen
   advance: IV access + cardiac monitor + benzo administered + psychiatric safety screen
3. 3CONTEXT
   Stimulant exposure timeline + dose + route + frequency (chronic daily user vs binge); concurrent medications + substance use (alcohol, opioids, benzos); psychiatric history (depression, anxiety, ADHD); social context (housing, support); reason for cessation; concurrent β-blocker (raises rebound severity); chronic-stimulant cardiomyopathy history; HIV/HCV risk factors
   inputs: age
   advance: comprehensive med rec + cessation reason + psychiatric history + social context documented
4. 4RED_FLAGS
   Suicide risk (high in stimulant withdrawal "crash" phase — psychiatric emergency); ICH (severe rebound HTN can cause ICH); aortic dissection (chronic stimulant + HTN raises risk); demand ischemia/MI (NE surge in CAD or chronic-stimulant cardiomyopathy); concurrent β-blocker exposure (worsens rebound by leaving alpha-vasoconstriction unopposed); concurrent active intoxication crisis (recurrent withdrawal cycle suggests active use pattern not just clean cessation); β-blocker exposure error if patient already received metoprolol/esmolol/propranolol pre-recognition (anticipate paradoxical worsening + give phentolamine to reverse)
   inputs: sbp, depression_and_suicide_screen, agitation_and_tremor_assessment
   actions: htn_emergency, cocaine_chest_pain
   advance: RED flags screened + life-threats addressed + psychiatric safety assured + ICH/dissection/MI ruled in/out
5. 5INITIAL_WORKUP
   ECG + serial troponin q3-6h × 2 if chest pain or chronic stimulant cardiomyopathy suspected; UDS (amphetamine class — confirms recent use clearing); CMP + Mg + CK + lactate; CXR (cardiomegaly, pulm edema); CT head if focal neuro deficit (rebound HTN ICH risk); CTA chest if back pain or BP differential (dissection); bedside echo if chronic stimulant cardiomyopathy suspected
   inputs: ecg_12_lead, troponin, urine_drug_screen, creatinine
   actions: panel.cardiac, panel.renal
   advance: workup documented + ICH/dissection/MI ruled in/out + cardiomyopathy screened
6. 6BRANCHING_WORKUP
   If STEMI → cath lab (chronic stimulant cardiomyopathy + acute HTN can precipitate Type 2 MI); if dissection → CTA + emergency CT surgery + parent aortic-dissection HTN engine; if ICH → AHA/ASA 2022 ICH pathway + IV nicardipine target SBP 130-140; if cardiomyopathy + cardiogenic shock → cardiogenic shock engine; if active stimulant intoxication overlap (UDS positive at high level) → active-use methamphetamine engine; if iatrogenic (prescription stimulant held during OR or rehab) → consider stimulant restart with supervised taper plan
   advance: syndrome-specific pathway activated
7. 7TREATMENT
   STEP 1 BENZODIAZEPINE FIRST: Lorazepam 1-2 mg IV q5-10 min (or diazepam 5-10 mg IV) — sympatholytic + reduces HTN + reduces tachy + treats agitation/anxiety + addresses dysphoria component (AHA 2008 Class I PMID 18391116 + AHA 2024 stimulant update; principle extended from active intoxication framework). STEP 2 NICARDIPINE IV: 5 mg/h IV titrate q5-15 min by 2.5 mg/h, max 15 mg/h — first-line BP control per AHA 2025 HTN emergency. STEP 3 PHENTOLAMINE: 1-5 mg IV q5-15 min titrate — pure alpha-blocker reverses rebound NE-driven alpha-vasoconstriction; rescue if concurrent β-blocker therapy worsens rebound. STEP 4 NTG IV: 5-200 mcg/min titrate as alternative or adjunct (vasodilation + coronary vasodilation). STEP 5 CCB ALTERNATIVE: verapamil 5-10 mg IV or diltiazem (cocaine framework extended to stimulant withdrawal per shared pharmacology). LABETALOL: debated as in cocaine/meth — theoretically OK as mixed α/β but small β-effect may worsen unopposed alpha; AHA 2024 says reasonable as add-on AFTER alpha-blockade. STEP 6 STIMULANT RESTART CONSIDERATION: if iatrogenic (prescription stimulant held during OR, rehab admission, or hospitalization), consider supervised restart at lower dose with planned taper over 1-2 weeks; coordinate with PCP/psychiatry. AVOID isolated β-blocker monotherapy (unopposed alpha principle — Lange NEJM 1989 PMID 2522592). STEP 7 PSYCHIATRIC CARE: address co-occurring depression + suicide risk with psychiatry consult; suicide watch if active ideation; medication for depression component (mirtazapine has some evidence in stimulant withdrawal per Coffin PMID 32049330).
   inputs: sbp, dbp, heart_rate
   advance: benzo titrated + nicardipine bridge + BP at target SBP <160 + agitation controlled + suicide risk addressed
8. 8DISPOSITION
   ICU/step-down for q15-30 min BP, telemetry, suicide watch if active ideation, observation 24-48 h minimum (rebound less sustained than active intoxication but psychiatric component ongoing); psychiatry consult for ongoing care during admission; addiction medicine consult
   advance: monitored bed assigned + 24-48h observation plan + psychiatry + addiction medicine consults booked
9. 9MONITORING
   Continuous ECG + telemetry; q15-30 min BP × 24 h; serial troponin q3-6h × 2 if chest pain or chronic CMP; suicide watch if active ideation; mental status + agitation scale q2h; CIWA or stimulant-equivalent withdrawal scale; benzo titration to symptoms not just BP
   inputs: sbp, heart_rate
   actions: panel.cardiac
   advance: BP at target + ACS ruled out + agitation/depression managed + psychiatric safety assured + UDS clearing
10. 10FOLLOWUP
    Stimulant use disorder (StUD) treatment — CONTINGENCY MANAGEMENT has strongest RCT evidence (Connors Annu Rev Clin Psychol 2018 PMID 29494256); no FDA-approved MAT for StUD (mirtazapine + naltrexone-bupropion combo modest benefit per Trivedi NEJM 2021 PMID 33497547 + Coffin JAMA Psychiatry 2020 PMID 32049330); cardiology follow-up if MI/cardiomyopathy occurred; ECHO at 3-6 months to assess for chronic stimulant cardiomyopathy reversibility with abstinence (Schürer JACC 2017); BP regimen if persistent HTN; psychiatric care for depression component (high suicide risk during early abstinence — close follow-up); harm reduction; HIV/HCV screening; PrEP if applicable; support groups (NA/CA, SMART Recovery); IF prescription-stimulant iatrogenic withdrawal — coordinate with prescriber for supervised taper plan + advance-supply system + perioperative protocol
    advance: StUD treatment booked (contingency management + behavioral therapy + psychiatry) + cardiology + repeat echo at 3-6 mo if cardiomyopathy + perioperative protocol if iatrogenic