Undiagnosed Hypertension in the ED Setting An Unrecognized Opportunity by Emergency Nurses

RESEARCH Undiagnosed Hypertension in the ED Setting An Unrecognized Opportunity by Emergency Nurses Authors: Paula Tanabe, RN, PhD, Rebecca Steinmann, RN, MS, Matt Kippenhan, MD, Christine Stehman, and Christopher Beach, MD, Chicago, Ill Paula Tanabe, Illinois ENA, is Post-Doctoral Fellow, Institute for Health Services Research and Policy Studies & Emergency Medicine; Matt Kippenhan is Clinical Instructor, Division of Emergency Medicine; Christine Stehman is a fourth-year medical student; and Christopher Beach is Assistant Professor, Division of Emergency Medicine, Northwestern University, Feinberg School of Medicine, Chicago, Ill. Rebecca Steinmann, Illinois ENA, is Clinical Educator, Children s Memorial Hospital, Chicago, Ill, and formerly an advanced practice nurse, Emergency Department, Northwestern Memorial Hospital, Chicago, Ill. This project was supported by an Excellence Academic Medicine grant from the State of Illinois and Northwestern Memorial Hospital and an endowed fund donated by Abra Prentice Wilkin to emergency medicine. Dr Tanabe is currently supported as a Ruth L. Kirschstein National Research Service Award postdoctoral fellow at the Institute for Health Services Research and Policy Studies of Northwestern University s Feinberg School of Medicine under an institutional award from the Agency for Healthcare Research and Quality. For reprints, write: Paula Tanabe, RN, PhD, 417 S Jefferson, #408, Chicago IL 60607; E-mail: p-tanabe@northwestern.edu. J Emerg Nurs 2004;30:225-9. 0099-1767/$30.00 Copyright n 2004 by the Emergency Nurses Association. doi: 10.1016/j.jen.2004.01.009 Introduction: Hypertension is often undiagnosed, untreated, undertreated, and poorly controlled. Many patients use the emergency department as their primary source ofhealth care, and the emergency department represents an opportunity to identify undiagnosed. We sought to (1) identify the prevalence ofelevated blood pressures in low-acuity patients and (2) describe the existing practice ofreassessment, treatment, and referral of abnormal vital signs in these patients. Methods: We conducted a retrospective study of88 ED patients at an academic medical center. All patients meeting Emergency Severity Index level 4 or 5 criteria (low acuity) were eligible. The following variables were recorded: triage level, medical history and medications, disposition, and all blood pressures. The investigators independently reviewed and reached consensus regarding the following outcome variables: the need for and actual treatment of elevated blood pressure, and the need for and referral for blood pressure recheck after discharge. Results: Thirty-seven patients (45%) had by definition on arrival. Systolic was more common. Ten ofthe patients (27%) with elevated blood pressures had documented rechecks prior to discharge in the emergency department, and only one patient was referred for follow-up. Twenty-seven out of37 low-acuity patients (73%) who presented with elevated blood pressures had no documentation ofthe blood pressure being rechecked and no documentation ofthe patient being referred. Conclusion: Our data suggest that important opportunities for education and follow-up of are being missed. June 2004 30:3 JOURNAL OF EMERGENCY NURSING 225

Approximately 25% of the US population or 50 million persons have diagnosed. 1 Despite the recognition of this epidemic and the existence of many guidelines (Table 1), largely remains undiagnosed, untreated, poorly controlled, and often undertreated. 2 Recent data suggest that of the 50 million persons with, 31% of the population are unaware they are hypertensive, 17% are aware they are hypertensive but have not been not treated, and only 23% of patients with are taking medications and have achieved blood pressure control. 3 Hypertension seems to be found commonly in the emergency department. In fact, the Centers for Disease Control and Prevention recently reported that only 30% of ED patient visits in 2001 were associated with a documented blood pressure of z140/90. 4 The hospital emergency department continues to serve as the primary place where many persons access health care. In 2000 there were more than 40 million ED visits (37%) for injury-related complaints. 5 These injuries occur primarily in a healthy population, many of whom may not have a primary physician. During the ED visit, every patient routinely has a blood pressure reading taken. The US Preventive Services Task Force found good evidence that blood pressure measurement can identify adults at increased risk for cardiovascular disease due to high blood pressure... 6 The majority of patients with are asymptomatic. We believe the ED setting may be an ideal setting in which to identify an entirely new group of patients with potentially undiagnosed. This group of patients otherwise would have their remain undetected for many years and be placed at an increased risk of cardiovascular and renal disease. Emergency physicians and nurses may play an important role in the identification of undiagnosed and can provide important education and referral for these patients, as well as for patients with previously diagnosed but poorly controlled. The primary purpose of our study was to: (1) identify the prevalence of patients with elevated blood pressures during an unrelated ED visit, and (2) describe the existing practice of reassessment, treatment, and referral for these patients. Methods STUDY DESIGN We performed a population-based, retrospective, crosssectional study of 88 Emergency Severity Index (ESI ) level 4 and 5 (low-acuity) ED patients who presented to our emergency department from May through October 2001. This sample was selected as a subset of patients from a larger triage study of 402 patients. The study was reviewed and approved by our Institutional Review Board with exemption from patient consent. STUDY SETTING AND POPULATION The study was conducted at a large academic urban emergency department with more than 70,000 patient visits and a 25% admission rate. All patient visits during the study period meeting ESI level 4 or 5 criteria were eligible for inclusion. STUDY PROTOCOL Patient records were selected from a larger data set of 402 ED visits by using the following process: patient records (10 admitted and 10 discharged records) were selected from the ED log for every tenth day beginning with May 1, 2001, through Oct 1, 2001. For each day, every tenth patient was selected until 10 admitted and 10 discharged patients were selected for each day. From this sample (N = 402), all patient records assigned ESI level 4 or 5 were reviewed (N = 88). MEASURES The following independent variables were abstracted from the medical record: demographics, chief complaint, medical history, antihypertensive medication use, discharge diagnosis, disposition, referral instructions, and all blood pressure readings obtained during the ED visit. At our institution, vital signs are routinely obtained at triage for all patients, including ESI level 4 and 5 patients. 7,8 After review of the literature and discussion and consensus agreement among the investigators, was defined as systolic blood pressure z140 or diastolic blood pressure z90. These criteria meet the definition of stage 1 226 JOURNAL OF EMERGENCY NURSING 30:3 June 2004

TABLE 1 Classification and management of blood pressure for adults aged 18 years or older BP classification or 2, as defined in the seventh report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure 2 (Table 1). The investigators reviewed the record of each patient with an elevated blood pressure upon presentation and determined the following: injury-related versus illnessrelated complaint, need for ED treatment of blood pressure, actual treatment of the elevated blood pressure, need for referral after discharge from the emergency department, and actual referral for blood pressure check follow-up. Blood pressures that were not rechecked and found to be abnormal initially were considered to need outpatient referral. Actual referral was considered to have occurred only if documentation was noted in the medical record. Consensus of the need for treatment was reached by individual case-by-case discussion by the investigators as a group. DATA ANALYSIS Data were entered into Microsoft Access and analyzed with SPSS version 11.5. Descriptive statistics were used to analyze the data. Chi-square statistic and odds ratio were calculated to determine the odds of having a blood pressure z140/90 given a past medical history of. Results Systolic BP, mm Hg Diastolic BP, mm Hg Lifestyle modifications Normal <120 and <80 Encourage Pre 120-139 or 80-89 Yes Stage 1 140-59 or 90-99 Yes Stage 2 z160 or z100 Yes BP, Blood Pressure. Reprinted with permission from The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. JAMA 2003;289:2560-72. Of the 402 patients reviewed, records from 88 patients met inclusion criteria. Data were analyzed for 83 patients with complete data. The sample mean age was 37.0 years TABLE 2 Odds of ED blood pressure z140/90 with a history of * Hypertension in emergency department No in emergency department Total + History of 8 2 10 History of 29 43 72 Total 37 45 82 * P =.037; OR = 5.93. Most patients with blood pressure z 140/90 in the emergency department did not have a history of, although patients with a history of were almost 6 times more likely to have blood pressure z 140/90 in the emergency department. with a standard deviation of 19 and a range of 1 to 93 years. The sample included 30 women and 58 men. Ethnic distribution is described as follows: white, 43%; African American, 32%; Hispanic, 10%; Asian, 0; other, 10%; and missing data, 5%. Thirty-seven patients (45%) presented with either an elevated systolic or diastolic blood pressure. There were 34 incidences of elevated systolic blood pressure and 15 incidences of elevated diastolic blood pressure. Twentynine of the patients (78%) presented with a chief complaint that was injury related. Reassessment practices were poor in our sample. Ten (27%) of the patients with elevated blood pressures had documented rechecks prior to discharge from the emergency department. Only 10 of the 37 patients with elevated blood pressures had a previous history of. However, patients with a history of were 5.93 times more likely to to have blood pressure z 140/ 90 in the emergency department (OR = 5.93; P =.037) (Table 2). Only 7 of the 37 patients with elevated blood pressure were currently taking antihypertensive medications. These patients had a prior history of. No patients were treated or admitted for their blood pressure while in the emergency department. One patient who specifically presented to the emergency department for a refill of his blood pressure medicine was given a follow-up appointment and a prescription. There was no evidence of referral for blood pressure recheck or any June 2004 30:3 JOURNAL OF EMERGENCY NURSING 227

follow-up instructions in any discharge instructions for any other patient. Discussion Our data demonstrate that 45% of patients with low-acuity complaints presented to our emergency department with by definition. Based on the documentation, these blood pressures were infrequently reassessed prior to discharge from the emergency department, and there was no documented referral of patients for follow-up. Our data verify recent findings in which only 36.8% of patients with elevated blood pressures were rechecked prior to discharge and only 2% received follow-up instructions for blood pressure recheck. 9 The clinical relevance of this finding in our sample is unknown. The elevated blood pressure may have been overlooked and not reassessed because of a perceived negligible clinical impact based on the patients complaint and physician or nurse perception of the importance of the finding. Patients with injury-related complaints may have an elevated blood pressure response because of pain or anxiety, 4 and, in the past, the clinical impact has been thought to be low. Elevated systolic blood pressures in a clinic setting have been described as white coat. 1 Initially, elevated blood pressures rechecked after treatment in the emergency department have been found to decrease, and this phenomenon has been described as a regression to the mean. 10 More recent data dispute this explanation. Backer and Decker 11 demonstrated findings similar to our data and were able to report the significance of a single elevated blood pressure reading in the emergency department. Patients identified in the emergency department with received follow-up blood pressure checks within 6 months. Seventy-six percent of those who received a follow-up blood pressure check again demonstrated elevated pressures on recheck. Pain was not found to contribute to increases in blood pressure. The investigators recommend blood pressure follow-up checks for any patient who presents with a single abnormal blood pressure reading. A second study by Chernow et al 12 also demonstrated similar findings; 59% of men and 78% of women seen in the emergency department with elevated blood pressures were again found to have either significant or borderline on a followup visit. Again, pain was not found to contribute to increases in blood pressure. The overall proportion of patients with a painful diagnosis was 71%, 71%, and 70%, respectively, in groups identified as having significant, borderline, and normal blood pressure on follow-up. We believe it is important that all abnormal vital signs, in particular blood pressures, be rechecked prior to patient discharge. Nurses can take an active role in patient counseling and recommend blood pressure follow-up. This also gives the nurse an opportunity to perform important patient teaching on the significance of. A recent survey of ED patients investigated patients interest in preventive health education. Fortytwo percent of the sample expressed the desire to receive blood pressure screening information. 13 Patient education is a critical role of the ED nurse. None of the elevated blood pressures in our sample required treatment in the emergency department. This finding reflects current, generally accepted practices that caution against attempting to lower blood pressure without evidence of organ damage to the heart, brain, retina, aorta, or kidneys. 14 Treatment based on a single blood pressure recording in the emergency department, for the majority of asymptomatic patients who present with nonhypertensive-related complaints, is impractical and unsafe. There is also general agreement that patients with elevated blood pressures should be referred for primary care follow-up. 14 What is the significance of our findings? Whereas it has been recognized that initially elevated blood pressures in the emergency department may not just be related to pain and may remain elevated when re-evaluated in several months, the ultimate number of patients with actual that can be identified through ED screening has not been identified. Could the identification and early screening of these patients help recognize undiagnosed? Should emergency physicians and nurses be expected to identify potential undiagnosed in the emergency department? The impact of early detection of could be dramatic. If ED physicians and nurses begin to recognize and refer patients for blood pressure recheck and follow-up, 228 JOURNAL OF EMERGENCY NURSING 30:3 June 2004

thousands of patients every year could potentially be diagnosed earlier and begin antihypertensive therapy. We also recommend further research in this area to determine the effect of a formalized screening and referral process. Limitations and Future Directions A significant limitation of this study was the retrospective collection of data; we relied only on what was documented in the medical record. The physician or nurse may have noted and discussed the elevated blood pressure with the patient and instructed them to recheck their blood pressure or to seek follow-up with their primary care physician. Our data may exaggerate the lack of referral because it was not charted. A second limitation is our small sample size and the limited generalizability because data were collected only at one site. Conclusions 7. Wuerz R, Milne L, Eitel D, Travers D, Gilboy N. Reliability and validity of a new five level triage instrument. Acad Emerg Med 2000;7:236-42. 8. Wuerz R, Travers D, Gilboy N, Eitel D, Rosenau A. Implementation and refinement of the emergency severity index. Acad Emerg Med 2001;8:170-6. 9. Garrett R, Brice J. The management of asymptomatic patients with elevated blood pressures in the emergency department [abstract]. 8th Annual UNC Emergency Medicine Research Forum, Chapel Hill, NC; April 16, 2003. 10. Pitts S, Adams R. Emergency department and regression to the mean. Ann Emerg Med 1998;31:214-8. 11. Backer H, Decker L, Ackerson L. Reproducibility of increased blood pressure during an emergency department or urgent care visit. Ann Emerg Med 2003;41:507-12. 12. Chernow S, Iserson K, Criss R. Use of the emergency department for screening: a prospective study. Ann Emerg Med 1987;16:180-2. 13. Llovera I, Ward M, Ryan J, LaTouche T, Sama A. A survey of the emergency department population and their interest in preventive health education. Acad Emerg Med 2003;10:155-60. 14. Shayne P, Pitts S. Severely increased blood pressure in the emergency department. Ann Emerg Med 2003;41:513-29. A significant number of patients with low-acuity complaints presented to the emergency department with elevated blood pressures that were infrequently reassessed, and patients were not referred for blood pressure followup. Emergency nurses and physicians can play a more important role in the identification and education of patients with previously undetected. REFERENCES 1. US Department of Health and Human Services Agency for Healthcare Research and Quality. Evidence report/technology/ assessment. Utility of blood pressure monitoring outside the clinical setting. Publication no. AHRQ 03-E004, November 2002. 2. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. JAMA 2003;289:2560-72. 3. Hyman D, Pavlik V. Characteristics of patients with uncontrolled in the United States. N Engl J Med 2001;345:479-86. 4. McCaig L, Burt C. National Hospital Ambulatory Medical Care Survey: 2001 Emergency Department Survey. Advance Data from Vital and Health Statistics, US Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics 2003;335. 5. McCaig L, Nghi L, Statistics DoHC. National hospital ambulatory medical care survey: 2000 emergency department summary. Adv Data Vital Health Stat 2002;326:1-31. 6. Sheridan S, Pignone M, Donahue K. Screening for high blood pressure, a review of the evidence for the U.S. preventive services task force. Am J Prev Med 2003;25:151-8. June 2004 30:3 JOURNAL OF EMERGENCY NURSING 229