Hypertensive Crisis

Definition

Severe elevation in blood pressure (SBP >=180mmHg or DBP >=120mmHg) with or without end-organ dysfunction

Categories

Hypertensive Urgency:

• BP elevation without end-organ dysfunction
  • Can still be associated with headache, dyspnea, epistaxis, palpitations, anxiety
  • Largely a consequence of inadequate HTN treatment or non-compliance

Hypertensive Emergency:

• BP elevation with end-organ dysfunction 
  • Evidence of damage to the retina, kidneys, heart, arteries and/or brain

Gestational Hypertensive Emergency:

• Severe HTN persisting >15mins plus end-organ dysfunction.
  • Severe preeclampsia, eclampsia, hemolysis, elevated LFTs, low platelets (HELLP) syndrome

Pseudo Hypertensive Crisis:

• Transient BP elevations from external stimulus
  • Pain, anxiety, stress, urinary retention, BP measurement errors
  • NO end-organ dysfunction
  • White-coat hypertension (see below)

             

Epidemiology

Most Affected Population:

• Elderly
• African Americans
• Men
• Patients with new or rapid BP elevation 
  • More susceptible to end-organ dysfunction at lower BPs because they haven't had chronic compensation/adaptation

Prevalence:

• 1-2% of general HTN patients
• Up to 11% of HTN patients admitted to hospital
• Up to 0.5% of all ED visits
• Pseudo-hypertensive crisis ~35% of inpatient HTN crisis, 91% outpatient HTN crisis

Etiology

Risk Factors for all HTN crisis:

• CHF, CAD, CKD, DLD, DM, Stroke, prior HTN

Causes:

• Primary HTN
  • Medication non-compliance
  • Inadequate treatment
• Secondary HTN
  • Renal artery stenosis
  • Arteritis 
  • Kidney pathology (think pre-renal, intra-renal, post-renal!)
• Endocrine
  • Pheo
  • Cushing
  • Hyperaldo
  • Renin tumour
  • Hyperthyroid
  • Carcinoid
• Obstructive Sleep Apnea 
  • Think hypoxia causing erythropoiesis, more RBCs in the blood raises BP
• Coarctation of the aorta
• Alcohol withdrawal
• Drugs!
  • Medications (withdrawal from anti-HTN meds, especially beta-blockers)
  • Recreational (cocaine, SSRI serotonin syndrome, etc.)
• Pregnancy 
  • Pre-eclampsia and eclampsia
• Neurogenic (head injury, infarction, hemorrhage, tumour)
• Acute stress
  • trauma, burns
• Pain
• Guillian-Barre Syndrome

Clinical Presentation

 

Complaints:

• Pulmonary edema (23%)
  • SOB, WOB, cough, orthopnea
• Heart failure (12%)
  • Chest pain, dyspnea, palpitations
• Headache
• Neurological Deficit
• Seizures
• Asymptomatic (common)

Ask about:

• Duration of prior HTN
• Recent BP measurements
• Cardiovascular risk factors
• Comorbidities
• Neuro symptoms
  • headache, nausea, vomiting, weakness, numbness, tingling
  • visual disturbance!
• Cardio/resp symptoms
  • SOB, orthopnea, cough, fatigue
• Sleep apnea
• Diaphoresis (pheo?)
• Dysphagia (Guillian-Barre?)
• Urinary hesitancy
• Red flag headache symptoms (SAH?)
  • Sudden onset, worst headache ever
• Red flag chest pain (aortic dissection?)
  • Sudden onset, severe pain radiating to the back
• Drug Use
  • Prescription (e.g. anti-HTN, erectile dysfunction meds), OTC (e.g. NSAID), herbal, recreational (e.g. cocaine)

Physical Exam:

Step 1: Confirm BP yourself with properly fitting cuff! If a true crisis, inform SMR/staff ASAP!

Step 2: Assess for end-organ dysfunction

• Fundoscopy
  • Retinopathy (above and left, compared to normal above and right), hemorrhages, exudate, papilledema
• Full neurological exam
  • Unilateral signs uncommon without ischemic brain injury
  • Mental status? Signs of encephalopathy?
• Vascular
  • Pulses in all extremities vs. central
• Cardiac
  • Rate and rhythm
  • Murmurs
  • Volume status and JVD
  • PMI
  • Is this patient in heart failure? (see below... keep in mind volume overload from other sources... nephrotic syndrome, cirrhosis, hypoalbuminemia, etc.)

           

• Abdomen
  • Renal bruits?
  • AAA?
• Head & Neck
  • Carotid bruits? 
  • JVD?
  • Head injury?
• Respiratory
  • Wheezing?
  • Crackles?

Diagnostic Testing

Blood Pressure & Heart Rate:

• >180/120 mmHg for hypertensive emergency and urgency
• Heart rate typically more elevated with hypertensive emergency
  • This makes sense, compensation for dysfunctional perfusion of the end-organs that are being damaged!
• >160/110 mmHg for >15mins in pregnancy

End Organ Dysfunction:

• Physical exam!!
• ECG
  • Myocardial ischemia
  • Secondarily for getting a sense of LVH (chronicity, heart failure)
• BNP
  • Heart failure
• CBC
  • MAHA
• LFTs
  • Liver dysfunction
• Chest x-ray or CT
  • Pulmonary edema?
• Head CT
  • Neuro ischemia
• Coagulation studies
  • Liver dysfunction
  • Also important for gauging risk of bleeding 
• Creatinine
  • Kidney dysfunction

Narrowing the Diagnosis:

• Urinalysis
  • metanephrines (pheo)
  • RBCs, protein, casts (renal dysfunction)
• Lytes
  • Hyperaldosteronism?
• Bladder ultrasound
  • Outlet obstruction
• Renal Ultrasound
  • Artery stenosis (secondary HTN)?
• CT head
  • Trauma? Ischemia? Hemorrhage?
• Echocardiogram
  • Heart failure?
• Creatinine

 

Management

IV Fluids:

• ONLY if volume-depleted
  • Give NS (0.9%) or Lactated Ringer's 
  • In order to avoid hypoperfusion or hypotension when anti-hypertensive therapy started

Anti-HTN Medication Principle:

• SLOW (high risk of hypoperfusion)
  • <25% reduction in the first few hours (no more than 20% in the first hour)
  • Exceptions!!
    • Acute Aortic Dissection
      • Target SBP <120mmHg within first hour and HR <60bpm
      • This patient is bleeding from/into their largest artery and will die soon without aggressive treatment
    • Ischemic stroke
      • Consider TPA, management can be complicated
      • Hypertensive encephalopathy 
      • Target MAP reduction of 20-25% immediately
        • Acute cardiogenic pulmonary edema
          • Immediately reduce SBP <140 mmHg
        • Eclampsia, severe pre-eclampsia, HELLP
          • Immediately reduce SBP to <160 mmHg and DBP to <105 mmHg
      • Acute intracerebral hemorrhage (see below)?

                                        

Hypertensive Urgency:

• Place patient supine for 30-45 minutes before drugs
• Oral anti-HTN commonly used to lower BP to <160/95 in the first 48 hours.
  • Nicardipine 20-40mg po q8-12h
  • Captopril 25-50mg po q8-12h
  • Labetolol 200mg po, then 200-400mg po q6-12h
• Close monitoring!!

Hypertensive Emergency:

• This patient needs to be in the ICU
• IV anti-HTN
  • Nicardipine 5mg/hr and titrating up
  • Sodium nitroprussied 0.3-0.5mcg/kg/min titrating up
  • Labetolol 0.3-1mg/kg slow injection then boluses
  • Esmolol 500mcg/kg over 1 minute then continued infusions
• Consider arterial catheterization for accurate BP measurements
• Manage the end-organ damage!
  • BP targets and meds change depending on concurrent ACS, perioperative HTN, renal failure, preeclampsia, etc.
• Transition to oral anti-HTN as soon as stable and tolerating PO meds

Prognosis

Overall mortality ~3.7%

• ~4.6% in HTN emergency
• ~0.8% in HTN urgency

Citation, and more information available at:

DynaMed [Internet]. Ipswich (MA): EBSCO Information Services. 1995 -. Record No. T114059, Hypertensive Crisis; [updated 2018 Nov 30, cited 2020-Aug-05]. Available from https://www.dynamed.com/topics/dmp~AN~T114059. Registration and login required.