Blood pressure decrease prior to initiating pharmacological therapy in nonemergent hypertension

Emergency Department-Provided Home Blood Pressure Devices Can Help Detect Undiagnosed Hypertension

INTRODUCTION

Emergency departments (EDs) are critical sites for hypertension (HTN) screening. Home blood pressure (BP) monitoring (HBPM) is used routinely in outpatient settings, yet its utility after the ED visit for those with elevated BP in the ED is unclear.

AIM

In this pilot study, we assessed if HBPM could detect HTN in patients with elevated in-ED BP.

METHODS

From September 2014 to July 2017, we recruited adult patients at an urban, academic ED with a triage BP ≥ 120/80 mmHg and no history of HTN into this prospective cohort observational study. After their ED visit, participants obtained BP measurements for two weeks using a validated HBPM. HTN was considered probable if the average HBPM BP was ≥ 135/85 mmHg. We calculated the proportion of participants whose ED BP measurement accurately predicted HTN using HBPM after discharge.

RESULTS

Of 136 participants enrolled, 93 (68%) returned the HBPM with at least four home BP measurements [mean number of measurements obtained: 29 (SD: 17, range 4-59)]. Participants' median age was 40 years-old (IQR 34-48); 55% were female, 19% were black, and 58% were white. Forty-six percent of participants with elevated in-ED BP had HTN in follow-up.

CONCLUSIONS

For patients with elevated BP in the ED, HBPM could be valuable for determining which patients have HTN and require expedient follow-up.

National trends in the emergency department management of adult patients with elevated blood pressure from 2005 to 2015

Emergency department (ED)-based screening and referral of patients with elevated blood pressure (BP) are recommended by 2006 and 2013 American College of Emergency Physicians guidelines; however, it is unknown if these recommendations or disparities in care impact clinical practice. The objectives of the study were to assess temporal trends in antihypertensive prescriptions, outpatient follow-up referrals, and diagnosis of hypertension (HTN)/elevated BP and to identify potential disparities by patient characteristics. Using the 2005-2015 National Hospital Ambulatory Medical Care Survey, we examined the frequency and trends over time of antihypertensive prescriptions, outpatient follow-up referrals, and BP diagnoses for US ED visits by adult patients with an elevated triage BP and identified potential disparities in management by patient demography and socioeconomic status. Of the 594 million eligible ED visits by patients from 2005 to 2015, 1.2% (1.0%-1.4%) received antihypertensive prescriptions at discharge, 82.3% (80.0%-83.6%) outpatient follow-up referrals, and 2.1% (1.9%-2.4%) an HTN/elevated BP diagnosis. There were small annual increases over time in the odds of antihypertensive prescriptions at discharge (adjusted odds ratio [aOR] 1.05 [1.00-1.10]), follow-up referrals (aOR 1.04 [1.01-1.07]), and HTN/elevated BP diagnosis (aOR 1.05 [1.02-1.08]). For BPs ≥160/100 mm Hg, prescriptions were more common for Blacks (aOR 2.36 [1.93, 2.88]) and uninsured patients (aOR 1.81 [1.38, 2.38]), and diagnoses were more common for Blacks (aOR 1.95 [1.70, 2.24]) and uninsured patients (aOR 1.30 [1.09, 1.55]). These data suggest little change in and the need for improvement in the management of ED patients with elevated BP, despite the American College of Emergency Physicians guidelines, and raise concern about patient care disparities.

High-Risk Patients with Hypertension: Clinical Management Options

Hypertension, one of the most common human diseases worldwide, affects nearly 1 billion individuals. Complaints related to hypertension are commonly evaluated and treated in the acute care settings such as emergency departments and acute care medical clinics. The evaluation, treatment, and disposition of these patients require thorough knowledge of potential complications and treatment options. This manuscript details a structured approach to evaluating high-risk patients with acute hypertension-related complaints and provides recommendations for treatment and disposition.

Course of untreated high blood pressure in the emergency department

Introduction

No clear understanding exists about the course of a patient's blood pressure (BP) during an emergency department (ED) visit. Prior investigations have demonstrated that BP can be reduced by removing patients from treatment areas or by placing patients supine and observing them for several hours. However, modern EDs are chaotic and noisy places where patients and their families wait for long periods in an unfamiliar environment. We sought to determine the stability of repeated BP measurements in the ED environment.

Methods

A prospective study was performed at an urban ED. Research assistants trained and certified in BP measurement obtained sequential manual BPs and heart rates on a convenience sample of 76 patients, beginning with the patient arrival in the ED. Patients were observed through their stay for up to 2 hours, and BP was measured at 10-minute intervals. Data analysis with SAS PROC MIXED (SAS Institute, Cary, North Carolina) for regression models with correlated data determined the shape of the curve as BP changed over time. Patients were grouped on the basis of their presenting BP as normal (less than 140/90), elevated (140–160/90–100), or severely elevated (greater than 160/100) for the regression analysis.

Results

A statistically significant downward trend in systolic and diastolic BP was observed only for those patients presenting with severely elevated BPs (ie, greater than 160/100).

Conclusion

We demonstrate a statistically significant decline in systolic and diastolic BP over time spent in the ED only for patients with severely elevated presenting BPs.

Provider self-report and practice: reassessment and referral of emergency department patients with elevated blood pressure

BACKGROUND

We attempted to identify patient factors associated with blood pressure (BP) reassessment and to compare health-care provider self-reported reassessment and referral to actual practice in an emergency department (ED) setting.

METHODS

Provider reassessment and referral practices were determined through systematic review of 1,250 medical records at five EDs. Medical records were included if patients were > or =18 years, nonpregnant, presented with a systolic (SBP) > or =140 or diastolic BP (DBP) > or =90 mm Hg, and discharged. A separate questionnaire obtained self-reported practice patterns of health-care providers. Multivariate logistic regression identified factors associated with patient BP reassessment and referral.

RESULTS

Of 1,250 patients, only 57% underwent BP reassessment and 9% received a referral for outpatient management. The most significant independent variables related to a reassessment were as follows: treatment of elevated BP in the ED (odds ratio (OR): 6.05; 95% confidence interval (CI): 1.80-20.31), chest pain (OR: 3.90; 95% CI: 2.37-6.42), and presence of an ED reassessment protocol (OR: 2.49; 95% CI: 1.77-3.50). The most significant factors associated with a referral included treatment of elevated BP in the ED (OR: 5.55; 95% CI: 2.72-11.32), presence of a reassessment protocol (OR: 2.58; 95% CI: 1.32-5.05), and a BP reassessment (OR: 2.56; 95% CI: 1.34-4.89). For self-reported practice patterns, 379 (72%) health-care providers completed questionnaires. Providers consistently overestimated their referral practices, yet the mean referral threshold values reported (SBP, 150 mm Hg; DBP, 93 mm Hg) were lower than the mean BP values of patients who actually received a directed referral (SBP, 170 mm Hg; DBP, 97 mm Hg, P < 0.0001).

CONCLUSIONS

Reassessment and referral of discharged ED patients with elevated BP was infrequent and health-care providers overestimate their reassessment and referral efforts.

The validity of emergency department triage blood pressure measurements

OBJECTIVE

Automated blood pressure (ABP) devices are ubiquitous at emergency department (ED) triage. Previous studies failed to evaluate ABP devices against accepted reference standards or demonstrate triage readings as accurate reflections of blood pressure (BP). This study evaluated ED triage measurements made using an ABP device and assessed agreement between triage BP and BP taken under recommended conditions.

METHODS

A prospective study was conducted at an urban teaching hospital. Patients were enrolled by convenience sampling. Simultaneous automated and manual triage BPs were obtained using one BP cuff with a Y-tube connector. Research assistants were certified in obtaining manual BP as described by the British Hypertension Society (BHS). Patients were placed in a quiet setting, and manual BP was repeated by American Heart Association (AHA) standards. Data analysis was performed using methods described by Bland and Altman. The ABP device was assessed using Association for the Advancement of Medical Instrumentation (AAMI) and BHS criteria.

RESULTS

One hundred seventy-one patients were enrolled. Systolic BP (sBP) range was 81 to 218 mm Hg; diastolic BP (dBP) range was 43 to 130 mm Hg. Automated vs. manual sBP difference was 3.8 +/- 11.2 mm Hg (95% confidence interval [CI] = 2.1 to 5.4); dBP difference was 6.6 +/- 9.0 mm Hg (95% CI = -7.9 to -5.2). Manual triage BP vs. AHA standard SBP difference was 11.6 +/- 12.8 mm Hg (95% CI = 9.1 to 14.1); dBP difference was 9.9 +/- 10.4 mm Hg (95% CI = 7.9 to 12.0). The ABP device failed to meet AAMI criteria and received a BHS rating of "D." Poor operator technique and extraneous patient and operator movement appeared to hamper accuracy.

CONCLUSIONS

ABP triage measurements show significant discrepancies from a reference standard. Repeat measurements following AHA standards demonstrate significant decreases in the measured blood pressures.

Emergency department hypertension and regression to the mean

STUDY OBJECTIVE

To evaluate the importance of regression to the mean in the assessment of asymptomatic hypertension in the emergency department.

METHODS

This was an historical cohort study of patients in the adult ED of a large urban teaching hospital. THe main outcome was changed in diastolic blood pressure (DBP). Subjects were 195 consecutive hypertensive patients with two sets of vital signs. Patients with specified acute conditions potentially associated with abnormal blood pressure were excluded, as were patients given vasoactive medications.

RESULTS

A statistical formula was used to predict the average blood pressure for hypertensive patients, using the observed mean and standard deviation of an all-patient sample. Given a threshold of 90 mm Hg, the expected mean DBP for hypertensive patients was 102.7 mm Hg, compared with an observed value of 104.5 mm Hg. Given an observed correlation coefficient of .73 between first and second measurements, a formula for regression to the mean predicted a spontaneous blood pressure decline of 7.2 mn Hg. A mean decline if 11.6 mm Hg was observed. The decline of 4.4 mm Hg more than expected among asymptomatic hypertensives was similar to the spontaneous decline of 3.7 mm Hg observed in the all-patient sample.

CONCLUSION

Patients who present with asymptomatic hypertension in the ED on average experience a spontaneous decline in blood pressure after they arrive. Most of this effect can be explained by regression to the mean. A small amount of this drop may represent attenuation of an initial alerting reaction.

Dose-response evaluation of oral labetalol in patients presenting to the emergency department with accelerated hypertension

STUDY OBJECTIVE

Dose-response evaluation of oral labetalol (100, 200, or 300 mg) on heart rate and systemic blood pressure in emergency department patients with hypertensive urgency (diastolic blood pressure, 110 to 140 mm Hg, and no end-organ evidence of hypertensive emergency).

METHODS

This acute-treatment, dose-ranging study used a randomized, double-blind, parallel design. Patients with supine diastolic blood pressure of 110 to 140 mm Hg after 30 minutes of bedrest received an oral dose of labetalol. Supine blood pressure and heart rate were measured manually and recorded hourly for four hours after dose. Diastolic blood pressure of 100 mm Hg or less or a 30-mm Hg reduction in diastolic blood pressure was considered a treatment success.

RESULTS

Two hundred fifty-five patients were evaluated for inclusion, and 36 patients (19 women and 17 men; mean age, 44 years; age range, 23 to 67 years) were studied. The most frequent reason for exclusion was a spontaneous decrease in diastolic blood pressure to less than 110 mm Hg (31%) with bedrest. There were 12 patients in each treatment group. Compared with baseline, the 100-mg dose significantly (P less than .05) reduced heart rate at three and four hours after dose, and the 300-mg dose significantly (P less than .05) reduced heart rate at one, two, and three hours after dose; the 200-mg dose did not significantly affect heart rate. All doses produced a significant decrease in systolic and diastolic blood pressures at one, two, three, and four hours after dose compared with baseline. There were no statistically significant differences between treatment groups with regard to systolic or diastolic blood pressure or heart rate at baseline or one, two, three, or four hours after dose. At two hours after dose, diastolic blood pressure control was observed in 75%, 58%, and 67% of patients receiving 100, 200, and 300 mg, respectively (P = .903). At four hours after dose, diastolic blood pressure control was observed in 50%, 64%, and 67% of patients receiving 100, 200, and 300 mg, respectively (P = .755). A comparison of treatment success rates between the two time periods showed a waning of response with the 100-mg dose of labetalol at hour 4 compared with hour 2 (P less than .05). No adverse effects were observed.

CONCLUSION

Labetalol provides safe and effective treatment for hypertensive urgencies when administered orally in doses of 100 to 300 mg.

Evaluation of drug therapy for treatment of hypertensive urgencies in the emergency department

Oral nifedipine (N) and clonidine (C) are often used in the treatment of hypertensive urgencies; however, until recently, there were no comparative studies using the same patient population. The authors reviewed the records of hypertensive patients treated in the emergency department between October 1, 1987 and September 30, 1988. Selected patients had a diastolic blood pressure (DBP) of greater than 115 mm Hg without evidence of acute end organ damage. Patients were stratified into three treatment groups: N, C, and group 3 (G3). G3 received a variety of drug therapies but not exclusively N or C. Systolic blood pressure (SBP), DBP, mean arterial pressure (MAP), percent decrease in MAP (%MAP), time to lower blood pressure, admissions, and discharges were evaluated. Efficacy and safety were defined as reaching a DBP less than 110 mm Hg but %MAP of no greater than either 25% or 40%, respectively. Thirty-five N, 32 C, and 27 G3 patients were identified with no statistical difference between groups in race, gender, pretreatment SBP, DBP, or MAP. N, C, and G3 significantly reduced SBP, DBP, and MAP (P less than .01). Comparing N, C, and G3, no differences were observed in %MAP, admissions, discharges, efficacy, or safety. Time required to decrease blood pressure differed between all three groups (44 +/- 32 N v 77 +/- 57 C v 152 +/- 94 min G3) (p less than .05). These results indicate that N, C, and a variety of drug therapies are equally effective and safe in the treatment of hypertensive urgencies.