A 55-year-old female presents to the emergency department from her family physician’s office for concern for hypertension. The patient reports she had a routine appointment, and during the vital signs check, her blood pressure read 190/100 mmHg. The patient denies any significant medical history other than a carpal tunnel release one week ago, when she believes they remarked that her blood pressure was elevated. Her physical exam, including her neurologic exam is unremarkable. Her blood pressure is 186/102, pulse of 86, respirations of 16, and oxygen saturation of 100% on room air.
Elevated blood pressure is common in the ED and may be associated with end-organ damage. However, most patients have asymptomatic markedly elevated blood pressure, which lacks the potential morbidity and mortality of hypertensive crises. Estimates from prior studies show that hypertensive-related complaints comprise 0.5-3% of all ED visits [1-3]. A minority of these visits represent hypertensive emergencies. Historically, markedly elevated blood pressures (>180/120 mmHg) without evidence of end organ dysfunction have been referred to as hypertensive urgencies. Recent papers call into question the utility of the “hypertensive urgency” diagnosis, and multiple clinical guidelines and policies have called for cessation of acute treatment of this entity [4-6]. Yet, the translation of this evidence into clinical practice takes a significant amount of time, and patients are still referred to the ED for asymptomatic markedly elevated blood pressures.
Classification
Hypertensive disorders are classified into two major categories: those with end-organ dysfunction and those without end organ dysfunction. Hypertensive emergencies represent the former, characterized by markedly elevated blood pressures (>180/120 mmHg) along with end organ dysfunction such as myocardial infarction or dissecting aortic aneurysm (see Table 1 below) [5]. Severe hypertension without evidence of end organ dysfunction represents the latter category, which has been variably defined. Classically, markedly elevated blood pressures (>160-180/100-120 mmHg) without evidence of end-organ dysfunction have been referred to as hypertensive urgency. Recently, the American College of Emergency Physicians (ACEP) introduced the term asymptomatic severely elevated blood pressure, indicating the lack of urgency in treating this condition [4].
In the ACEP clinical policy, the term “asymptomatic severely elevated blood pressure” replaces the term “hypertensive urgency.” The semantics may be confusing since hypertensive urgency can be associated with mild symptoms such as shortness of breath, epistaxis, headache, or anxiety according to the Joint National Committee (JNC) [5]. Although ACEP’s definition of asymptomatic markedly elevated blood pressure suggests that a patient must be “asymptomatic,” this is not the case. ACEP’s clinical policy, along with other guidelines, state only that the patient should have no symptoms of end organ dysfunction, not that the patient must be entirely asymptomatic [4].
Significance
Hypertension is common, affecting approximately 30% of the U.S. population. The blood vessels of hypertensive patients have altered capacitance which, when exceeded, may cause endothelial injury and insufficient organ perfusion. Uncontrolled hypertension is associated with increased risk of myocardial infarction, stroke, heart failure, and renal insufficiency. A 2016 Canadian retrospective cohort study found that patients presenting to the emergency department with a primary diagnosis of hypertension had low overall mortality with a seven-day mortality of 0.17%, 30-day mortality of 0.43%, and 1-year mortality of 2.5%. Complications and mortality rates were much higher in the 8% of patients who were admitted to the hospital and lower in those discharged from the ED [3]. This underscores the difference between worrisome hypertensive emergencies and the well-appearing patients who warrant less acute treatment.
Evaluation of Hypertension in the Emergency Department
First, the provider should confirm the absence of symptoms of end-organ dysfunction. Symptoms of end-organ dysfunction may include focal neurologic deficit, active severe chest pain, respiratory distress, seizure, or coma (see chart above). If any of these findings are present, the patient should be treated as a hypertensive crisis. Treatment goals and rate of blood pressure reduction vary, depending on the specific disease process. See Table 2 below for details on treatment.
In the absence of any of these symptoms, any workup should be directed towards the patient’s underlying complaint rather than the blood pressure.
The 2013 ACEP clinical policy on treatment of hypertension in the emergency department states that screening for acute target organ injury by means of urinalysis, serum creatinine, or ECG is not routinely required. Historically, abnormal test results occur in 5-7% of asymptomatic patients and often represent chronic findings rather than acute derangements [4,7]. Given the low yield of testing with no clear evidence of benefit for acute intervention, this testing can probably be deferred to the outpatient setting.
Yet, providers may consider screening tests in patients with poor follow up, particularly if the results of testing will change disposition. Certain testing may be needed in those patients in whom certain anti-hypertensives are considered, such as renal function and potassium in patients started on angiotensin converting enzyme inhibitors (ACE-I) or angiotensin II receptor blockers (ARBs).
Treatment
Referral to the ED is unnecessary for asymptomatic markedly elevated blood pressure. A 2016 retrospective cohort study of outpatients presenting with blood pressures >180/120 mmHg and no symptoms of end organ dysfunction found no difference in major cardiac or cerebrovascular effects within six months between patients referred to the hospital for treatment and those who were not [7]. Most asymptomatic hypertensive patients in this study were treated as outpatients, with a minority of the patients referred to the hospital, a total of 426 patients or 0.7% of the cohort. While patients treated on an outpatient basis were slightly more likely to have uncontrolled hypertension after the first month, the likelihood of MACE remained < 1% for both groups
Once a patient is in the ED, acute lowering of blood pressure in patients with asymptomatic severely elevated blood pressure is generally not necessary. This is supported by the ACEP clinical policy, noting that the deleterious consequences of hypertension occur over a period of years rather than acutely. Rapid lowering of blood pressure in hypertensive patients has been found in some studies to lead to deleterious outcomes [4,5]. Further, acute blood pressure lowering in the ED has not been found to result in significantly lower blood pressures at follow up [8]. No current evidence based or guideline recommendations exist for a blood pressure cut-off at which point an asymptomatic patient must be acutely treated.
Emergency providers may elect to treat patients with severely elevated blood pressures based on presence of other symptoms and patient and provider preferences. For example, some external facilities may require lowering blood pressure before accepting a patient (ex: a psychiatric unit). In this instance, one may choose a single oral dose of a quick-acting agent such as metoprolol tartrate (immediate release) 25 mg or carvedilol 12.5 mg. This is not an evidence-based practice, rather a relatively benign approach to get the patient to appropriate definitive care.
Further, if a patient has poor follow-up, the ED provider may initiate antihypertensive therapy. The JNC-8 guideline recommended first-line anti-hypertensives are listed in Table 3 below.
Hypertension is common in the ED and is usually not associated with an acute medical emergency. If the history and physical are not concerning for end organ dysfunction, acute testing and treatment in the ED is not routinely necessary. Should the patient lack outpatient follow up, one may elect to start an oral antihypertensive and refer the patient to a primary care physician. Thiazide diuretics and calcium channel blockers are first line for any race. ACE-inhibitors and angiotensin receptor blockers are also first line for non-black patients. The studies that serve as the basis for these racial recommendations found smaller blood pressure reductions in blacks compared with non-blacks [9]. A large retrospective cohort study also found worse outcomes in blacks on ACE-inhibitors compared with other anti-hypertensives [10]. Historically, hypertension in blacks is thought to be less dependent on angiotensin II, possibly due to renin suppression in blacks; however, some evidence supports that this difference is due to salt intake and individual salt-sensitivity [11].
Case Resolution
This patient falls into the category of asymptomatic markedly elevated blood pressure. You may recheck her blood pressures, as the blood pressure may trend down. After discussing with the patient that based on her current examination she is ACE-inhibitors and there is no need for diagnostic testing the ED, you engage in shared decision making about starting an anti-hypertensive today or following up with her primary care physician for close monitoring and treatment. She tells you she will call her doctor in the morning and she would like to defer treatment until she sees her primary care physician. You counsel her on the importance of long-term blood pressure control and include discharge instructions.
REFERENCES
- Zampaglione B, Pascale C, Marchisio M, Cavallo-Perin P. Hypertensive urgencies and emergencies: prevalence and clinical presentation. Hypertension. 1996;27(1):144-147.
- Chiang WK, Jamshahi B. Asymptomatic hypertension in the ED.Am J Emerg Med. 1998;16 (7):701-704.
- Masood S, Austin PC, Atzema CL. A Population-Based Analysis of Outcomes in Patients With a Primary Diagnosis of Hypertension in the Emergency Department. Ann Emerg Med. 2016;68(3):258–267.e5.
- Wolf SJ, Lo B, Shih RD, Smith MD, Fesmire FM. Clinical policy: Critical issues in the evaluation and management of adult patients in the emergency department with asymptomatic elevated blood pressure. Ann Emerg Med 2013;62(1):59–68.
- The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. National High Blood Pressure Education Program. Bethesda (MD): National Heart, Lung, and Blood Institute (US); 2004 Aug. Report No.: 04-5230
- Heath I. Hypertensive Urgency — Is This a Useful Diagnosis ? JAMA Intern Med 2016;8(1):13–4.
- Patel KK, Young L, Howell EH, et al. Characteristics and Outcomes of Patients Presenting With Hypertensive Urgency in the Office Setting. JAMA Intern Med. 2016;176(7):981–8.
- Nakprasert P, Musikatavorn K, Rojanasarntikul D, Narajeenron K, Puttaphaisan P, Lumlertgul S. Effect of predischarge blood pressure on follow-up outcomes in patients with severe hypertension in the ED. Am J Emerg Med. 2016;34(5):834–9.
- James PA, Oparil S, Carter BL et al. 2014 Evidence-Based Guideline for the Management of High Blood Pressure in Adults: Report From the Panel Members Appointed to the Eighth Joint National Committee (JNC 8). JAMA. 2014;311(5):507-520.
- Ogedegbe G, Shah NR, Phillips C et al. Comparative Effectiveness of Angiotensin-Converting Enzyme Inhibitor-Based Treatment on Cardiovascular Outcomes in Hypertensive Blacks Versus Whites. Journal of the American College of Cardiology. 66(11):1224-1233. 2015.
- Flack JM, Sica DA, Bakris G et al. Management of High Blood Pressure in Blacks: An Update of the International Society on Hypertension in Blacks Consensus Statement. Hypertension. 56(5):780-800. 2010.