Assess immediate organ injury first; make a separate, sustainable plan for persistent hypertension. This adult ED synthesis distinguishes acute treatment from prevention. BP values are in mmHg.
1) Terminology & Triage
Severe hypertension: SBP >180 or DBP >120 without acute organ damage.
The 2024 AHA acute-care statement distinguishes asymptomatic elevation from hypertensive emergency by new or worsening organ injury, not the number alone. Assess neurological, cardiac, renal, retinal and aortic findings. Pregnancy has a separate pathway.
Repeat the measurement with a suitable cuff and supported positioning; address pain, distress, missed medication and other contributors. Acute illness and impaired autoregulation make abrupt pressure drops hazardous. Observational evidence raises concern about treating asymptomatic inpatient readings, particularly with IV medication; this does not establish benefit from immediate normalization. Avoid reflex IV treatment and do not dismiss persistent hypertension as anxiety.
2) Condition‑Specific Targets for Hypertensive Emergencies
For nonpregnant, nonstroke emergencies without compelling conditions, 2025 guidance allows oral/parenteral therapy: SBP reduction ≤25% in hour one, <160/100 over 2–6 hours, then 130–140 over 24–48 hours if stable (Class 1/C-LD).
Aortic syndrome: 2022 guidance prioritizes monitored anti-impulse treatment and urgent specialist care. Use IV beta blockade unless contraindicated, adding a vasodilator if needed after rate control. Aim for HR 60–80/min and SBP <120, or the lowest pressure compatible with organ perfusion. A pressure target must not override shock or deteriorating perfusion.
Acute organ injury requires monitored care and syndrome-specific treatment. Pulmonary edema, myocardial ischemia and suspected catecholamine crisis require their own drug-selection pathway; do not transfer the aortic drug sequence to every emergency.
3) Stroke: Prioritize Perfusion — Precise Targets
The 2026 ischemic-stroke guideline preserves BP <185/110 before IV thrombolysis and <180/105 for the following 24 hours. For EVT, ≤180/105 during treatment and for 24 hours afterward is reasonable.
Without reperfusion or another urgent indication, routine lowering below 220/120 has no established early benefit. Above 220/120, the recommendation calls benefit from starting or restarting treatment within 48–72 hours uncertain; supporting text still describes an individualized initial 15% reduction. Involve the stroke team rather than applying a rigid general-emergency schedule.
After successful anterior-circulation LVO recanalization (mTICI 2b/2c/3), an intensive SBP target <140 during the first 72 hours is harmful without another BP indication. This does not call for automatic vasopressors when spontaneous SBP is below 140.
Spontaneous ICH: 2025 Class 2a guidance supports SBP 130–<140 for ≥7 days when presenting SBP is 150–220; stop antihypertensives below 130. Other hemorrhage/perfusion scenarios need individualized neurocritical care.
4) Pregnancy & the Peripartum Window
Pregnancy: confirm SBP ≥160 or DBP ≥110 within 15 minutes; lower below both thresholds within 30–60 minutes. Chronic goal: <140/90.
For severe pregnancy or postpartum hypertension, ACOG emergency guidance supports IV labetalol, IV hydralazine or immediate-release oral nifedipine, selected through the obstetric protocol and contraindication review. Pregnancy, pregnancy planning and breastfeeding require distinct medication-safety checks; do not copy a nonpregnant adult regimen.
ACOG postpartum guidance calls for BP assessment within 72 hours after severe hypertension and by 7–10 days postpartum for hypertensive disorders. New headache, visual symptoms, upper-abdominal pain or breathlessness requires urgent assessment, not a wait for routine follow-up.
5) Risk‑Based Treatment Thresholds (PREVENT™)
For confirmed nonpregnant adult averages, medication thresholds are ≥140 systolic or ≥90 diastolic regardless of risk; ≥130 or ≥80 with CVD, prior stroke, diabetes, CKD or 10-year PREVENT-CVD risk ≥7.5%. Lower-risk stage 1 warrants medication after persistent elevation despite 3–6 months of lifestyle treatment. Stage 2 favors two first-line drugs in one pill.
PREVENT estimates primary-prevention risk for adults aged 30–79 without established CVD. Do not extrapolate the calculator to children, pregnancy, older ages or inputs outside its validated range. The calculator does not replace disease-specific treatment decisions. Interpret any estimate in the clinical context rather than using the peak ED BP as a chronic baseline.
6) Measurement & Disposition
The 2025 ACEP policy addresses outpatient prescribing at ED discharge. Its Level C advice is to consider starting medication, supported by one Class III study, with follow-up recommended by consensus. It is optional, not a requirement for every elevated reading, and does not authorize acute number-lowering. Pregnancy, end-stage renal disease, hypertensive emergencies and other serious acute presentations are outside its scope.
For asymptomatic noncardiac inpatients, avoid extra intermittent oral or IV doses solely to lower BP; not planned maintenance.
Before prescribing, review adherence, contraindications and the ability to monitor safety and response. Arrange a named follow-up clinician and explain the plan. Persistent diagnostic uncertainty, another acute illness or an unworkable discharge plan can justify continued assessment.
For home confirmation, NICE NG136 provides a specific method: use a validated device and suitable cuff, seated with the arm supported; obtain two readings at least one minute apart each morning and evening for 4–7 days, ideally seven. Exclude day one and average the rest. This measurement method does not import NICE treatment thresholds into the AHA risk framework.
7) Practical ED Algorithm
Confirm measurement → assess acute injury → follow the relevant emergency pathway or plan sustained outpatient control.
Document the repeat BP, clinical assessment, medication decision and follow-up arrangements. Give clear urgent-return instructions for new neurological symptoms, chest/back pain, dyspnea, visual change or markedly reduced urine output. A safe discharge plan matters more than a normal monitor number.
