Hypertensive Emergency - ACEM Fellowship Notes

see also: [[Asymptomatic hypertension]] see: [Dunn Drugs for hypertensive emergencies](x-devonthink-item://3A53CC26-DF87-4612-A710-F7DF5B2CF97A), [ other anti-hypertensive agents](x-devonthink-item://C96A2A22-36D5-4720-AE0A-4D6C589591D8) > [!Key Points] > - hypertensive encephalopathy would be a true HTN emergency > [!danger] Definitions > **hypertensive emergency**: systolic blood pressure >180 mm Hg and/or diastolic blood pressure >120 mm Hg associated with evidence of new or worsening end-organ damage (i.e. cardiovascular, renal or neurological). > > ~~**hypertensive urgency**: no evidence of end-organ dysfunction with a similarly elevated blood pressure.~~ > > Hypertensive urgency is an out-dated term (guidelines since 2004 have noted that it leads to overly aggressive management of pts with uncomplicated HTN); we now use [[Asymptomatic hypertension|Asymptomatic markedly elevated blood pressure]] # Associated conditions - [[Aortic dissection]] - [[Encephalopathy]] - Malignant HTN - [[ACS]] - [[Pulmonary oedema]] - [[Stroke]] - Renal Failure - preeclampsia - basal ganglia stroke / hypertensive stroke - [[haemorrhagic stroke]] - PRES | Organ | Conditions | | -------- | -------------------------------------------------------------------------------------- | | Brain | - [[Stroke]] - Hypertensive encephalopathy (PRES) - [[haemorrhagic stroke\|ICH]] | | Arteries | - [[Aortic dissection]] - [[Pre-eclampsia]] / HELLP / eclampsia | | Retina | - Gr III-IV keith-Wagner-Barker hypertensive retinopathy | | Kidney | - [[Acute Renal Failure\|AKI]] - thrombotic microangiopathy | | Heart | - [[Congestive Heart Failure\|Acute heart failure]] - Pulmonary oedema - [[ACS]] | # Treatment ## hypertensive urgency - nifedipine IR 10mg po - captopril 12.5mg po - clonidine 100mcg po - prazosin 2mg po **note:** - amlodipine has delayed action of onst, so does not achieve significant reduciton in GP quickly. can use amlodipine 5mg po if slower reduction is acceptible ## hypertensive emergency > ==Generally treat if BP above 220/140== > - reduce by no more than 25% within the first 2 hours. > - Use an intravenous infusion of a drug that has a **rapid onset** and **short duration of action** in order to enable a rapid control of blood pressure, and prevent a precipitous drop in blood pressure that may be difficult to correct. **IV push:** - [[hydralazine]] 1mg IV, Q1M up to 5mg - metoprolol IV 1mg same - [[labetalol]] also OK **Infusions:** - [[sodium nitroprusside]] 0.3mcg/kg/min IV - increase by 0.5mcg/kg/min Q5 min up to 10 mcg/kig/min - **esmolol** 500mcg/kg over 1 min, then 50-200 mcg/kg/min IV - GTN 10mcg/min, increase by 5mcg/min Q5 min up to 100mcg/min - labetolol 2-4mg/min IV until in range, then 5-20mg/hour ## Specific diseases table #tables | Disease | Drug | | ------------------------- | ------------------------------ | | [[haemorrhagic stroke]] | [[Nicardipine]] | | pregnancy | [[hydralazine]], [[labetalol]] | | [[Cocaine]] OD | benzos, phentolamine | | [[Aortic dissection]] | esmolol, nitroprusside | | [[Pulmonary oedema\|APO]] | GTN | ## hypertensive encephalopathy - decrease MAP by 10% to 15% or to a diastolic blood pressure of 100 to 110 mm Hg, whichever value is greater, **in the first hour**. - Centrally acting drugs that can affect mental status, such as clonidine, are not used. Camerons and eTG still recomend sodium nitroprusside nicardipine (similar to diltiezem) more popular now ## HTN + aortic dissection see: [[Aortic dissection]] - beta blocker first (reduce sheering stress) - then reduce afterload (eg sodium nitroprusside or [[labetalol]]) ## HTN + cocaine see: [[Cocaine]] - benzos - NO beta blockers (unbridled alpha) - phentolamine (alpha-1 blocker) ## HTN + pregnancy - magnesium - delivery - **hydralazine** - **labetalol** ## HTN + ACS/APO see: [[Pulmonary oedema|APO]] and [[ACS]] - IV GTN # Antihypertensives table #tables | Drug | indications | contraindications | dosing | mechanism | | -------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [[hydralazine]] | - hypertensive crisis - likely OK for cocaine | - 1st and 2nd trimester - SLE - caution IHD - aortic aneurysm - significant tachy | 1 - 5mg IV slowly Q 20 min | - vasodilation of arterioles - causes reflex tachy | | [[labetalol]] | - [[Pre-eclampsia]]/ eclampsia - pregnancy - [[Stroke]] pre-thrombolysis - [[Aortic dissection]] | - asthma - PVD - 2nd and 3rd deg HB - HR < 50 - CHF - RV failure 2/2 pulm HTN | 10 - 20 mg then 0.5 - 2 mg/min | - beta blocker and some alpha-blocking | | [[GTN]] | - [[Pulmonary oedema\|APO]] - hypertension - myocardial ischaemia - cocaine | - elevated ICP (can worsen it) - hypovolaemia - HOCM - tamponade - aortic or mitral stenosis - cor pulmonale - *viagra* | | B2 pregnancy | | [[Clonidine]] | - sedation - adjunct to opiate withdrawl - analgesia - irukandji syndrome - sometimes cocaine | - bradyarrhythmias (sick sinus, AV block) - renal impairment - liver impairment - depression - peripheral vascular disease | - po initially 50 - 100mcg BD - IV 150 - 300 mcg QID | alpha-2 blocker | | [[Nicardipine]] | - [[Stroke\|ischemic stroke]] - [[haemorrhagic stroke]] - hypertensive encephalopathy / PRES - *aortic dissection if cannot use beta blockers* - severe pre-eclampsia | - cardiogenic shock - bradycardia - hypotension - sick sinus syndrome - conduction delays - *severe aortic stenosis* → reducing afterload causes ↓ diastolic BP and worsens myocardial oxygenation - *contradicted* for ACS and unstable angina - caution in hepatic and renal impairment | | dihydropyridine CCB onset: 5-10 min duration: 15-30 min may have tocolytic effect if given in 3rd trimester preg | | phentolamine | - pheochromocytopma - 2nd line for cocaine-induced MI - extravasation ischaemia (infiltrate area with 10 - 15mL saline containing 5-10 mg phentolamine) | - hypotension - stroke, coronary artery disease, heart failure (reflex tachycardia) | 1mg IV Q 5 min (max 15 mg) | alpha 1 and alpha 2 blocker | | esmolol | - SVT / flutter - aortic dissection - thyroid storm | - bradycardia - shock - significant conduction disease / sick sinus - WPW - RV failure - caution asthma/COPD - pheochromocytoma (need alpha-blocker) - cocaine and other symathomimetic OD | | | | diltiezem | | | | | | verapamil | - revert SVT - rate control AF | - LV failure - hypotension - as with other CCBs - pregnancy (class C) | SVT or AF or flutter: 4-5 mg over 2-3 min, then 1mg/min IV up to 15mg | ? give peripheral Calcium first | | nifedipine | - HTN in pregnancy - [[Altidude illness#High altitude pulm oedema]] - raynaud's - tocolytic for preterm labour (otherwise is class C) | - cardiogenic shock - BP < 90 - bradycardia - sick sinus, conduction delays - LV failure - VT - don't use with beta blocker in elderly - grapefruit juice | po: 10-20mg BD | | | nimodipine | - prevent and treat vasospasm in [[Subarachnoid haemorrhage\|SAH]] | - if hepatic impairment, give 30mg Q4H | 60 mg po Q4 H IV usually central at 1mg/hour for 2 Hr then 2mg/H | give within 48 hours of SAH | | sodium nitroprusside | - hypertensive emergency (older drug) - reduce preload and afterload | - can cause cyanide toxicity - high output cardiac failure or septic shock (situations with ↓ peripheral vascular resistance) - avoid in pts with liver impairment or renal impairment (cyanide) - avoid if on viagra | 0.3 mcg/kg/min ↑ dose by 0.3mcg/kg/min Q2 min usually 0.5 mcg/kg/min max: 10 mcg/kg/min | causes precipitous drops in BP so not used much. do not stay on this for >72 hours half-life 2 min abrupt withdrawal can cause rebound HTN can cause cyanide toxicity in renal impairment and methemoglobinaemia. | | Prazosin | | - can cause postural hypotension, particularly after the first dose. - Avoid in heart failure. - Caution rebound tachycardia. - To minimise the risk of falls, start or resume therapy at the lowest dose, increase the dose slowly, monitor standing BP, and warn patients of this effect. | 0.5mg bd up to 1-10 mg bd | - alpha blocker | | Moxonidine | | | | |