Hypertensive emergencies

Manage now— do this, in order

• Decide first whether this is an emergency at all: with no acute organ damage — rest, re-measure, treat pain, anxiety or retention, restart oral therapy, follow up within days. Acute parenteral reduction in urgency or asymptomatic hypertension has no benefit and considerable evidence of harm.
• Set the ceiling before any drug: reduce mean arterial pressure by no more than 20–25% in the first hour, or to a diastolic of about 100–110 mmHg — whichever is the *smaller* fall. Never take the diastolic below 100 mmHg in the first hour. Then 160/100–110 mmHg over 2–6 hours, normalising orally over 24–48 hours. MAP = diastolic + (systolic − diastolic) ÷ 3.
• Labetalol is the workhorse: 20 mg IV over 2 minutes, then 20–80 mg every 10 minutes to a cumulative maximum of 300 mg, or infusion 0.5–2 mg/min. Avoid in asthma, COPD with wheeze, acute decompensated heart failure, second/third-degree block, bradycardia < 50/min. Alternatives: nicardipine 5 mg/hour IV (max 15 mg/hour), esmolol 500 microgram/kg then 50–200 microgram/kg/min, glyceryl trinitrate 5 microgram/min titrated, hydralazine 5–10 mg IV over 5–10 minutes.Doctor / NurseNot available at your setup — Infusion pump. Where continuous titration is not feasible, intermittent observed boluses are safer than an unmonitored infusion.
• Learn the exceptions by name: aortic dissection — systolic 100–120 mmHg and rate < 60/min within ~20 minutes, beta-blocker before vasodilator; acute ischaemic stroke — do not treat unless > 220/120 mmHg (185/110 if thrombolysing), then ≤ 15% in 24 hours; intracerebral haemorrhage — systolic 140 mmHg smoothly over the first hour, not below 130; pulmonary oedema — glyceryl trinitrate first line, furosemide 40–80 mg IV only if genuinely congested, no beta-blocker.Doctor / Nurse
• Pre-eclampsia/eclampsia: treat ≥ 160/110 mmHg, aim 140–150/90–100, never let the diastolic fall below 80 mmHg. Labetalol 20 mg IV then 40 mg then 80 mg at 10-minute intervals (max 300 mg), hydralazine 5 mg IV every 20 minutes (max 20 mg), or nifedipine 10 mg orally *swallowed*. Seizures: magnesium sulphate 4 g IV over 5–15 minutes then 1 g/hour for 24 hours; 2 g IV over 5 minutes for recurrence. Monitor patellar reflexes, respiratory rate > 12/min, urine output > 30 mL/hour; antidote calcium gluconate 1 g (10 mL of 10%) IV over 10 minutes.Doctor / Nurse
• Catecholamine excess (cocaine, amphetamine, phaeochromocytoma, drug withdrawal): benzodiazepine first — diazepam 5–10 mg IV repeated; phentolamine 2–5 mg IV every 5–10 minutes is the specific alpha-blocker; in clonidine or beta-blocker withdrawal reinstate the withdrawn drug. Never give unopposed beta-blockade — including labetalol alone — in catecholamine excess.Doctor / Nurse
• Sublingual or bite-and-swallow nifedipine capsules must never be used — the fall is precipitous and uncontrollable and has caused stroke, myocardial infarction and death. If an oral calcium channel blocker is appropriate, use a swallowed preparation and wait.
• Children — reduce more cautiously: no more than 25% of the total planned reduction in the first 8 hours, the rest over 24–48 hours; confirm the weight before drawing up any drug. Labetalol 0.2–1 mg/kg per dose IV over 2 minutes (max 20–40 mg) every 10 minutes or infusion 0.25–3 mg/kg/hour; nicardipine 0.5–1 microgram/kg/min titrated to 4–5. Do not give a fluid bolus to a hypertensive, oedematous, oliguric child unless volume depletion is certain.Doctor / Nurse
• Deterioration during treatment means you have lowered too far or too fast (new confusion, new focal deficit, chest pain, falling urine output): stop the infusion and give a cautious fluid challenge — for example 250 mL of 0.9% sodium chloride — do not give a vasopressor.