Virtual Doctors Forum: Hypertensive Crises

Information based on BMJ Best Practice Guidance: https://newbp.bmj.com/topics/en-us/27/

Definitions:

Hypertensive Urgency: blood pressure ≥ 180/110 mmHg without acute target-organ damage.

Hypertensive Emergency: severely elevated blood pressure (BP) associated with new or progressive target organ dysfunction.

Although the absolute value of the BP is not as important as the presence of end-organ damage, the systolic BP is usually >180 mmHg and/or the diastolic BP is >120 mmHg.

Q: Why is this a medical emergency?

A: Can lead to irreversible end organ damage

Image from https://www.accp.com/docs/bookstore/ccsap/ccsap2018b1_sample.pdf

Causes:

There are many possible causes of hypertensive emergency.

One very common cause is essential hypertension that is either undiagnosed or inadequately treated.

Another common cause of hypertensive emergency is secondary and resistant hypertension:

  • Renal: most common caused by underlying chronic disease, renal artery stenosis, acute glomerulonephritis, collagen vascular diseases, kidney transplantation.
  • Neurological: head trauma, spinal cord injury, autonomic dysfunction
  • Respiratory: obstructive sleep apnoea
  • Vasculitis
  • Endocrine: multiple causes- but rare and small print! These are also difficult to diagnose without extensive tests and investigations.
  • Pregnancy: pre-eclampsia, HELLP syndrome, and eclampsia are important causes of hypertensive emergency in women. THIS IS OFTEN TREATED DIFFERENTLY
  • Lifestyle factors:
    • excessive dietary salt intake,
    • obesity
    • alcohol consumption
    • smoking
    • drug use

Symptoms:

Neurological:

  • Blurry vision
  • Dizziness
  • Headache
  • Seizures
  • Change in mental status
  • Dysphagia (swallowing difficulty)
  • Numbness
  • Paraesthesia
  • Weakness

Cardiac:

  • Chest pain
  • Shortness of breath
  • Sweating
  • Orthopnoea (breathlessness when lying down)
  • Palpitations
  • Peripheral oedema

Renal:

  • Decreased urine output

Examination:

An appropriately sized cuff should be used for BP readings:

  1. The cuff bladder should encircle at least 80% of the upper arm and the cuff length should be greater than two-thirds the distance between the shoulder and elbow.
  • The arm should be supported at heart level during recordings.
  • Using too large a cuff could result in an underestimation of BP; too small a cuff could lead to overestimation.
  • BP readings should be taken from both arms and readings repeated after 5 minutes to confirm.

If there is a more than 20 mmHg pressure difference between arms, aortic dissection should be considered. This requires urgent transfer to a specialist hospital.

A fundoscopic examination should be performed, looking for the presence of papilloedema retinal haemorrhages, retinal exudates, or engorged retinal veins.

Fundoscopy: Papilloedema
Fundoscopy: Hypertensive Changes

A bedside neurologic exam is also required and should include:

  • testing of cognition
  • examination of the cranial nerves
  • checking gross motor strength and sensation
  • checking the patient’s gait

It is important to listen to the heart sounds to check for any new murmurs or additional sounds. It is also useful to check for artery bruits and whether there is any peripheral oedema present.

Investigations

Depending on clinic facilities, it may not be possible to perform any diagnostic tests, however it is useful to check the following as a minimum if you are able to:

  • FBC- to check for any abnormalities
  • U&E- may show renal impairment
  • Urinalysis- may show blood/protein which can signify end organ kidney damage
  • ECG- may show ischaemia or left ventricular strain pattern

See: https://litfl.com/left-ventricular-hypertrophy-lvh-ecg-library/

Overall the most important thing is to check for evidence of end organ damage as this is what distinguishes hypertensive urgency from hypertensive emergency.

Treatment:

This is according to the British National Formulary and the hyperlinks should link through to the correct doses for each medication.

Hypertensive Urgency (HU):

  • Use of sublingual nifedipine is not recommended.

A systematic review was carried out in the Journal of General Internal Medicine in 2018, which concluded that he optimal choice of antihypertensive agent remains unclear.

The full article can be accessed here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5880769/#!po=0.909091

Hypertensive Emergency (HE):

In UK guidelines, oral therapies are generally discouraged as first-line treatment options.

Intravenous treatment options include sodium nitroprusside [unlicensed], nicardipine hydrochloridelabetalol hydrochlorideglyceryl trinitratephentolamine mesilatehydralazine hydrochloride, or esmolol hydrochloride.

The precise choice of drug depends on the past medical history and clinical status of the patient.

It is important to control the patient’s BP, however bringing it down too quickly can also cause renal, cerebral, or coronary ischaemia and should therefore be avoided.

If you do not have access to IV medication, using an oral anti-hypertensive, as per HU guidelines, is likely to do less harm than leaving a patient untreated with grossly abnormal physiology and an increased risk of irreversible end organ damage.

If you are in doubt about how best to manage a case, don’t forget you can contact us at the Virtual Doctors for patient specific advice and guidance.

 

Making a Referral

As we have expanded and started to offer advice in Malawi and also take on more clinical officers in Zambia, we thought it would be helpful to do a quick post of what to include in your referral to the Virtual Doctors advisors.

The picture below highlights the most important information to include.

Observations are really important so that we can advise upon the urgency of a clinical decision and get an idea of how unwell your patient is.

Knowing their background- age, gender and whether they have known HIV is really helpful as we can then rule in or rule out certain diagnoses.

Understanding why they have come to see you and what their main complaint is, is probably the most important thing to know, but putting this in context, by knowing if they have any past medical history or take any medication is also very important. If they have no past history and take no medication, please say so!

As we reply upon what you tell us, sending us any relevant examination findings, including photos is really useful. You are our eyes in the field! Our advice can only be as good as the information we receive!

Part of the process is to help with learning and education. It is helpful for us to know what you are thinking. What do you think is going on with the patient? Most importantly, what are you worried about? what do you want help with?

Please try and be specific when possible. This will help us be able to offer you the best advice we can to benefit the patients and clinical officers using the service.

Diagram Slide1.jpg