Hypertension is a common chronic illness that affects 50 million individuals in the United States and approximately 30% of adults worldwide. United States emergency departments report > 900,000 annual visits for hypertension-related complaints and studies show that approximately one-third of patients with elevated blood pressure lack a formal prior diagnosis. These patients are at risk for long-term morbidity and mortality from cardiovascular, ocular, and neurological consequences. This review examines the most current evidence regarding emergency department treatment of asymptomatic hypertension, including differentiating hypertensive emergency from poorly controlled hypertension, recommendations for choosing appropriate treatment, determining the need for admission, and guidelines for disposition and follow-up.
You start your shift on Monday morning with a 52-year-old woman referred by her primary care physician’s office for a blood pressure of 190/120 mm Hg. She had been previously diagnosed with hypertension and presented for her regular physical that day. When you see her, she has a blood pressure of 160/100 mm Hg and denies headache, chest pain, shortness of breath, or any vision changes. Her physical exam is normal. She confesses that she has been poorly compliant with her hydrochlorothiazide. You wonder why she was sent to the ED, but now that she is here, what should you do?
Several patients later, you see a 35-year-old uninsured man presenting for an ankle sprain. His blood pressure is persistently elevated at 220/110 mm Hg during his stay. He carries no prior diagnosis of hypertension and only complains of severe pain in his ankle. Despite treatment with oxycodone and alleviation of his pain, he remains significantly hypertensive. You wonder if you should treat the blood pressure…
Your next patient is a 78-year-old woman who is brought in by her family for a concern of new-onset hypertension. She has no recent medical history and is on no medications. She had her blood pressure checked several times over the preceding weeks at a pharmacy, and it was consistently around 150/90 mm Hg. Her exam is normal. She does not have a family physician and the earliest appointment the family has been able to get with an internist is in 3 weeks. The family is appropriately worried and asks you if you could start her on medication, but you aren’t sure if this is the best way to manage this patient.
Emergency clinicians treat hypertension in a variety of contexts: the compliant patient on antihypertensive medications who notes an abnormal blood pressure, the asymptomatic patient with severely elevated blood pressure who carries no prior diagnosis, and the patient presenting in extremis with severe shortness of breath, chest pain, and markedly elevated blood pressure. The focus of this systematic review of the literature is the emergency department (ED) management of asymptomatic hypertension as opposed to hypertensive crisis or hypertensive emergency. Hypertensive emergency or crisis is defined as an acute elevation of blood pressure, typically ≥ 180/120 mm Hg, with end-organ damage involving the brain, heart, kidneys, vasculature, or retina.1,2 While a hypertensive emergency can occur de novo, it usually presents in patients with prior chronic hypertension. Hypertensive urgency is defined as severe hypertension without acute end-organ damage. Some groups advocate distinguishing hypertensive urgency from uncomplicated, severely elevated blood pressure, where patients with urgency have evidence of chronic target-organ damage (see Table 1).3
While there are many guidelines and individual articles on management of asymptomatic elevated blood pressure,1,4,5 there is much provider variability in treatment, largely due to the spectrum of the disease. This review outlines new findings in the field of hypertension, particularly as they pertain to the practice of emergency medicine, and suggests a management algorithm based on the best available evidence.
The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) defines normal blood pressure for adults ≥ 18 years of age as a systolic blood pressure of < 120 mm Hg and a diastolic blood pressure of < 80 mm Hg.1 Above this cut-off, blood pressure ranges are defined for prehypertension, stage 1 hypertension, and stage 2 hypertension. (See Table 2.) The guidelines suggest that the diagnosis of hypertension is based on the mean of 2 or more properly measured blood pressure readings on each of 2 or more office visits. However, more recently, ambulatory blood pressure and home blood pressure measurements have become acceptable alternatives for diagnosing hypertension. In clinical studies, the term markedly elevated blood pressure is synonymous with the JNC 7 definition of stage 2 hypertension. The stratification of patients into different blood pressure categories helps guide treatment.
The 2013 European Society of Hypertension and European Society of Cardiology (ESH/ESC) guidelines for the management of arterial hypertension have similar definitions for hypertension, but they divide blood pressures < 140/90 mm Hg into 3 categories (optimal, normal, and high-normal) instead adof using the terms normal or prehypertensive.6 See Table 3 for critical considerations in the ED treatment of hypertension.
A search using Ovid Medline® (www.ovid.com) was launched for articles published from January 1990 to December 2014. Keywords included hypertension, emergency department, emergency medical services, elevated blood pressure, and hypertensive urgency; 5878 articles were screened for inclusion and 187 articles were determined to be relevant for review. The Cochrane Database of Systematic Reviews was also searched and yielded 134 articles, 4 of which were deemed to be appropriate for this review. A search of the National Guidelines Clearinghouse (www.guideline.gov) produced 113 guidelines. Three guidelines were found to be relevant to the management of elevated blood pressure in ED patients. Additional references were selected from works cited in the reviewed articles.
1. “I aggressively treat all patients with elevated blood pressure initially, and then decide who needs to be admitted or discharged based on their response to therapy.”
It is wise to tailor diagnostic and management strategies to the individual patient and to distinguish patients with asymptomatic elevated blood pressure from those presenting with symptoms that are suggestive of end-organ damage or hypertensive emergency. While the former need a blood pressure recheck in days to weeks, the latter may need parenteral therapy and admission (frequently to the intensive care unit setting). Also, blood pressure that is elevated on initial triage measure may decrease without an intervention on recheck. While patients with asymptomatic elevation of blood pressure have a low likelihood of shortterm decompensation, those with hypertensive emergency need parenteral therapy to prevent potentially fatal acute end-organ damage.107
2. “I was reassured by her normal blood pressure in the ED, even though her doctor sent her in for a markedly elevated blood pressure in the office.”
Proper cuff size avoids underestimation of blood pressure in thin individuals and overestimation of blood pressure in obese individuals. Be aware of this with your thin elderly female patients. A standard adult or large-size cuff may lead to underestimation of their blood pressure in the ED.
3. “I gave him clonidine prior to his discharge. I didn’t think he needed to be admitted.”
In patients without end-organ hypertension symptoms or signs, discharge from the ED with follow-up for elevated blood pressure is appropriate. It is not advisable to treat these patients in the ED with parenteral or oral therapy to which they are naïve, simply to improve their vital signs while in the department. Drugs such as clonidine are not considered first-line therapy for hypertensive urgency. In patients who may have chronically elevated blood pressure, they can cause a significant drop in blood pressure, leading to a decrease in cerebral blood flow, with consequent syncope or even stroke.4
4. “The patient’s blood pressure was elevated, but she was well-appearing, so I followed the ACEP clinical policy recommendations and didn’t order any laboratory testing.”
While laboratory testing is not necessary in most patients presenting with symptomatic elevated blood pressure, patients should be screened for end-organ damage and the concerning causes of elevated blood pressure. All women of childbearing age should be asked if they are pregnant or recently gave birth. Undiagnosed pre-eclampsia can lead to renal failure, liver failure, seizures, and cardiovascular morbidity.
5. “The patient was here for a paronychia, I didn’t feel the need to scrutinize his high blood pressure.”
Patients frequently present with elevated blood pressure without symptoms. Hypertension is a widely prevalent disease and there can be a long latency from onset to development of endorgan damage. The ED offers a public health opportunity for early diagnosis, counseling, and referral.
6. “I didn’t address the patient’s elevated blood pressure of 180/100 mm Hg because I assumed that it was due to anxiety from being in the ED.”
Numerous studies support the replicability of ED blood pressures (particularly those above 160/100 mm Hg) in the outpatient setting. Blood pressure measurements should be repeated in these patients, and they should be informed of their abnormal blood pressure readings and receive expedient follow-up, with consideration for a prescription for a first-line antihypertensive medication.
7. “I didn’t counsel the patient on lifestyle strategies to decrease his elevated blood pressure because this is the role of the primary care provider.”
Many of our patients do not have a source of regular primary care or they have long waits to be seen by their primary care providers. Lifestyle changes are a benign, cost-effective, and efficacious means of decreasing blood pressure.
8. “A complete laboratory workup showed no abnormalities, so I felt comfortable discharging her.”
The ACEP clinical policy asserts that patients presenting with elevated blood pressure without a history or examination suggestive of hypertensive emergency need not have extensive laboratory investigations in the ED.7
References Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, random ized, and blinded trial should carry more weight than a case report. To help the reader judge the strength of each reference, pertinent information about the study will be included in bold type following the ref erence, where available. In addition, the most informative references cited in this paper, as determined by the authors, will be noted by an asterisk (*) next to the number of the reference.
Elizabeth M. Goldberg, MD
February 1, 2015