By Guest Author: Dr Yamema Esber
Myth: Severe asymptomatic hypertension (BP >180/110mmHg) needs urgent antihypertensive treatment.
Malady: If asymptomatic with no high-risk features, put the GTN patch away. Address obvious causes, such as pain. Consider slow therapy intensification with oral antihypertensives if BP is persistently elevated in a chronically hypertensive patient. Remember, strict in-hospital blood pressure management does not often translate to better clinical outcomes.
Let’s begin with a trip down memory lane: You’re a fresh-faced intern and have been called to review vasculopath Bob for a blood pressure (BP) of 190/95 mmHg. He has been admitted to hospital for management of a diabetic foot infection and has chronic everything – hypertension, type II diabetes, the works. He’s asymptomatic and is watching TV while drinking a cup of orange juice (what’s a fluid restriction anyway?). Bob’s nurse asks you to chart something to get his BP out of the yellow zone. You review the file and note his BP has never wandered south of 160 systolic, with occasional excursions to the 190-200s zone. You call your registrar, who well-meaningly advises you to slap on a GTN patch and call it a day.
As clinicians, we are driven by an urge to fix problems. We know that chronic hypertension (persistently elevated BP ≥130/80 mm Hg) has numerous long-term cardiovascular and renal harms. We are also taught to fear the dreaded “hypertensive emergency”, which is severe hypertension (BP >180/110mmHg) with evidence of new or worsening end-organ dysfunction [1]. These include neurological (hypertensive encephalopathy, haemorrhage), cardiac (heart failure), respiratory (acute pulmonary oedema), renal (acute kidney injury), and vascular (aortic dissection) complications. This is life-threatening, with protocols in place for rapid blood pressure reduction and close monitoring [2, 3].
In contrast, inpatient management of severe hypertension WITHOUT end-organ dysfunction is a more poorly investigated space. We can divide this phenomenon into “asymptomatic severe hypertension” and the emotive “hypertensive urgency”*, where there are mild symptoms such as headache or dizziness [1,2]. We are conditioned to treat these patients, subjecting them to stringent outpatient BP targets [4]. We think a SBP > 200 equals instant death, but the human body can both generate and cope with very high acute pressures. Venturing into literature pre-dating pedantic cardiologists and nephrologists, MacDougall and colleagues (1985) [5] reported extreme BP elevations during double leg press exercise (whatever that means) with mean systolic BP of 320mmHg (are you stressed reading this, because I am). There is also, unhelpfully, a dearth of guidance with a grand total of zero randomised controlled trials comparing management approaches to inpatient asymptomatic severe hypertension [1,4].
It is not benign to enthusiastically lower Bob’s BP with a GTN patch, an oral option like prazosin (beware postural hypotension!), or an intravenous antihypertensive if that’s your poison of choice. Firstly, blood pressure monitoring in an artificial environment while acutely unwell, in pain, anxious and sleep deprived does not reflect physiological baseline [1,4]. Secondly, if there is no evidence of end organ dysfunction, then asymptomatic severe hypertension is unlikely to cause significant harm in the acute period [1,3]. Your poorly controlled chronic hypertensive is probably regularly trending above systolic 190 at home without acute harm. Thirdly, aggressive blood pressure lowering in this population has been associated with poorer outcomes. Rastogi and colleagues [6] found higher rates of AKI, myocardial infarction and ischaemic stroke with aggressive oral or intravenous treatment in asymptomatic non-cardiac patients. Similar results, barring ischaemic stroke, and a higher risk of hypotensive episodes were reported by Anderson et al [7] in an older population (mean age 74). Remember, a dizzy delirious grandma is a fast-track to a fall.
So, if you’re seeing Bob on a night shift, what to do?
1. If Bob is truly hypertensive, do we need to treat urgently?
- There are several conditions where tight BP control and individualised targets are essential (e.g. acute stroke, intracranial surgery, aortic dissection, pregnancy). These patients or those with any end-organ damage should be managed as per protocol [1-4].
- The South-Eastern Sydney Local Health District (SESLHD) [3] also recommend considering high-risk features which incur a greater risk of complications from hypertension (e.g. previous history of hypertensive urgency or intracranial haemorrhage, untreated coronary artery disease) to individualise the need to treat.
2. Are there any reversible environmental, iatrogenic or emotional factors that could be contributing? Manage these if present [1,2].
- Remember amlodipine is not a treatment for pain.
- Consider contributing medications such as NSAIDs, corticosteroids and stimulants. And don’t forget the fun-drug variety (hospitalisation is seemingly not a contraindication to cocaine use) or withdrawal [1].
3. Is the patient already known to have hypertension?
- A one-off hospital reading is not a worthy substitute to multiple home and ambulatory BP readings used in the outpatient setting to confirm a new diagnosis of hypertension. If no previous diagnosis, outpatient monitoring should be advised in the patient’s discharge plan [4].
- If so, have all their regular medications been charted? (Gaynor et al report 41% [8] of acutely hypertensive patients were charted PRN antihypertensives rather than being continued on their home regimen.)
- If Bob’s outpatient BPs are just as atrocious as his inpatient readings despite regular antihypertensive therapy, AHA guidelines [1] suggest this could be a window of opportunity to intensify his treatment regimen. While this very specific population may benefit from careful treatment escalation, Mohandas and colleagues (2021) [9] found the use of PRN antihypertensives in addition to regular antihypertensives resulted in a greater risk of AKI, ischaemic stroke and in-hospital mortality. Moreover, in Rastogi and colleagues’ study [6], intensification of antihypertensives at discharge did not equate to improved BP control after one year. The verdict is not yet out on this one.
4. Treatment should be the exception, not the rule. If you decide to treat, SESLHD [3] suggests aiming for a slow 10mmHg reduction in the first 24 hours, and helpfully recommend some antihypertensive options. It can take days for a peak effect to be seen. Consider an altered calling criteria (with senior input, don’t be a gung-ho intern).
For those who have zoned out by now, allow me to summarise the management of asymptomatic severe hypertension – (almost always) don’t.
*A caveat on nomenclature – the latest American Heart Association statement guidelines [1] have actually dropped “hypertensive urgency” altogether because the emotive language makes you feel obligated to treat. The following stratification has been proposed instead: “hypertensive emergency”, “asymptomatic markedly elevated inpatient BP” and “asymptomatic elevated inpatient BP” (BP ≥130/80 mm Hg).
Giant’s Shoulders:
[1] American Heart Association 2024 Scientific Statement which goes into everything I’ve discussed in much greater depth.
[2] eTG page on Urgent control of elevated blood pressure
[3] An exhaustive guideline – the South Eastern Sydney Local Health District on assessing and managing inpatient hypertension
Also cited above:
[4] Australian Prescriber article on the measurement and management of hypertension: https://australianprescriber.tg.org.au/articles/blood-pressure-elevations-in-hospital.html
[5] MacDougall’s (1985) report on arterial blood pressure responses to heavy resistance exercise in body builders
[6] Rastogi et al (2021) on complications associated with pharmacological management of inpatient asymptomatic hypertension
[7] Anderson and colleagues (2023) article regarding a Veterans Health population: https://pubmed.ncbi.nlm.nih.gov/37252732/
[8] An (un)surprising study by Gaynor and colleagues (2018) identifying high incidence of forgetting to chart regular medications (a universal dilemma)
[9] Assessing the impact of PRN (on top of regular) antihypertensives – Mohandas et al (2021)
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