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1 Usefulness of the modified 0-10 Borg scale in assessing the degree of dyspnea in patients with COPD and asthma Authors: Karla R. Kendrick, RN, MSN, Sunita C. Baxi, MD, and Robert M. Smith, MD, San Diego, Calif Introduction Rapid assessment and monitoring is essential for patients with acute bronchospasm. However, tools for measuring dyspnea or the state of being short of breath are often limited to peak flow, blood gas analysis, and asking patients multiple questions about their breathing at a time when they find speaking difficult. We thus decided to examine a tool called the modified Borg scale (MBS) that had the potential to provide quick, easy, and rapid information about a patient s subjective state of dyspnea. This 0 to 10 rated scale gave our ED patients a device they could use to measure and evaluate their dyspnea. For this reason, we added it to the triage assessment practice and included it in all posttreatment assessment notes on patients with exacerbations of asthma or chronic obstructive pulmonary disease (COPD) who were seen in the emergency department and urgent care clinic. Study questions (1) Can patients with acute bronchospastic asthma or COPD adequately communicate their level of dyspnea using the MBS? (2) Does subjective improvement in the patient s dyspnea using the MBS correlate with improvements in pulmonary functions as measured by the peak flow meter and cutaneous oxygen saturation (SaO 2 )? Methods Routine and triage assessment of subjective dyspnea using the MBS was instituted at a hospital emergency department serving adult veterans. Concurrently, the MBS was added to our standardized treatment protocol for management of patients with bronchospasm. ED and urgent care records were reviewed to collect baseline and postrespiratory treatment data on peak expiratory flow rates (PEFR), MBS scores, and SaO 2 percentages. Karla R. Kendrick, San Diego County Chapter, is Staff Nurse III and Quality Improvement Facilitator for the Emergency Department and Urgent Care Clinic, Veterans Administration San Diego HealthCare System, San Diego, Calif; Karlak@ix.netcom.com. Sunita C. Baxi is a staff physician in the Section of General Internal Medicine and Geriatrics, Veterans Administration San Diego HealthCare System, and Associate Clinical Professor of Medicine at UCSD, San Diego, Calif. Robert M. Smith is Associate Chief of Staff for Health Care Analysis at Veterans Administration San Diego HealthCare System and Associate Clinical Professor of Medicine at UCSD, San Diego, Calif. For reprints, write: Karla R. Kendrick, RN, MSN, 4982 Marin Dr, Oceanside, CA Copyright 2000 by the Emergency Nurses Association /2000 $ /1/ doi: /men Results Four hundred male veterans aged 24 to 87 years presented with a chief complaint of dyspnea. The assessing physician identified 102 of these patients as having acute bronchospasm; 42 were diagnosed with asthma, and 60 were diagnosed with COPD. All study patients with acute bronchospasm were able to use the MBS to rate their perception of severity of dyspnea. As the peak flow measurements increased, the MBS scores of difficulty breathing decreased. For the asthma groups, the mean MBS score decreased from 5.1 at triage baseline to 2.4 after treatment. This finding indicated that a significant correlation existed between the change in MBS scores and the change in PEFR from pretreatment to posttreatment scores (r =.31, P <.05). As the peak flow increased, the MBS scores decreased. SaO 2 only slightly improved in the asthma group compared with the COPD group. For patients with COPD, the mean MBS score decreased from 6.0 at triage baseline to 3.0 after treatment. This finding indicated that a significant correlation also existed between the change in MBS scores and the change in PEFR from pretreatment to posttreatment scores (r =.42, P <.001). Cutaneous oxygen saturation also improved in the COPD group after treatment. The modality of treatment ordered by the physician was metered dose inhaler or nebulizer. These treatment modalities had no effect on the aforementioned results in the asthma or COPD group. Conclusions The MBS is a valid and reliable assessment tool for dyspnea. This study demonstrated that it correlated well with other clinical parameters and could be useful when assessing and monitoring outcomes in patients with acute bronchospasm. Patients who used the MBS rated it with a high degree of satisfaction on ease of use and found that the language in this scale adequately expressed their dyspnea. The ED triage and primary care nursing staff rated the MBS as highly satisfactory, stating that it was quick and easy to use. Respiratory assessment in the triage notes and nursing notes were streamlined to consistently include 3 respiratory measures: PEFR, MBS, and SaO 2. Long respiratory narratives were found to be unnecessary in many cases. In addition, the MBS helped to include an important element of subjective assessment when evaluating the severity of dyspnea. (J Emerg Nurs 2000;26:216-22) 216 Volume 26, Number 3

2 Kendrick, Baxi, and Smith/JOURNAL OF EMERGENCY NURSING Figure 1 Modified Borg scale. (Note: The word breathlessness was added in our version of the scale for clarification.) (From Burdon JGW, Juniper EF, Killian KJ, Hargrave FE, Campbell EJM. The perception of breathlessness in asthma. Am Rev Respir Dis 1982;126: Official Journal of the American Thoracic Society. by the American Lung Association.) The symptom of shortness of breath or dyspnea is one of the most common and significant complaints of patients with respiratory disease. The sensation of dyspnea is a sensory experience that is perceived, interpreted, and rated by the individual. 1-3 The nursing narrative assessment of a patient who comes to the emergency department with dyspnea usually includes counting the respiratory rate, characterizing the rhythm of respiration, and identifying the use of accessory muscles of respiration, skin color, the ability to speak in full sentences, and what triggered this episode. 4,5 Many nurses still use the question/answer type of narrative in their respiratory assessment and require patients to answer such questions as How far can you walk? and What relieves your shortness of breath? even if the patients are having great difficulty breathing. Many triage nurses have included additional objective information in their assessment, such as peak expiratory flow rate (PEFR) or forced expiratory volume (FEV 1 ) and/or cutaneous oxygen saturation measurement (SaO 2 ). However, ED patients are not routinely asked to actively participate in rating their dyspnea by either the ED nurse or the ED physician. Subjective assessment of dyspnea was not mentioned in the recent National Institutes of Health expert panel report for the diagnosis and management of asthma. 6 In sharp contrast, if a patient comes to the emergency department with chest or abdominal pain, the patient is often asked to rate his or her pain on a scale of 1 to 10. After assessing the origin of the pain, medication is ordered and administered on the basis of the patient s subjective pain response. We wanted to study whether a similar self-rating scale could be used for patients with varying levels of dyspnea. If such a scale is useful, how accurate is it? The literature includes a variety of studies that have attempted to understand how patients measure the sensation of dyspnea or shortness of breath. 1,7,8 Burdon et al. 9 used the modified Borg scale (MBS) with a group of patients with asthma to determine their perceived dyspnea as it related to specific pulmonary changes in air flow obstruction. These patients were shown the MBS, which is a vertical scale from 0 to 10 in which numbers are anchored with corresponding verbal expressions of progressively increasing intensity. The patients were asked to rate their dyspnea by selecting the number with the corresponding words that most appropriately described their sensation of breathlessness (Figure 1). Belman et al 10 found that the MBS was a reliable tool for quantifying dyspnea in subjects with COPD who were undergoing a 6-minute treadmill walk. Simon et al. 11 found that when patients were asked to June

3 JOURNAL OF EMERGENCY NURSING/Kendrick, Baxi, and Smith Figure 2 Protocol for management of patients with acute bronchospasm at the Emergency Department and Urgent Care Clinic at the VA San Diego HealthCare System, San Diego, Calif. describe their symptoms of breathlessness, they used a variety of expressions such as out of breath, can t breath, or chest tightness, which suggested that each patient was having a different sensory experience rather than a single experience. Using normal volunteers, Simon et al. 9 tested whether persons with induced dyspnea could distinguish between levels of breathlessness using the MBS. Their study found that subjects could distinguish between different sensations of breathlessness and that the term breathlessness may encompass multiple sensations. A study by Mador et al 12 measured dyspnea in patients with COPD during a 5-week exercise program. These investigators reported a strong linear relationship between MBS ratings and respiratory effort when combined with exercise. Wilson and Jones 13 compared use of a visual analogue scale and the MBS to measure dyspnea in healthy young volunteers during exercise. These investigators similarly reported that good correlation exists between the intensity of breathlessness described by MBS and the amount of work done during exercise. The literature review clearly showed that the MBS was a valid and reliable tool when used in pulmonary medicine and in exercise physiology studies. However, no data existed on its effectiveness when used as a triage and ongoing assessment tool in the emergency department. This study was conducted to test whether dyspnea as reported by ED patients with acute bronchospasm could accurately reflect their degree of cardiopulmonary dysfunction, as measured by the PEFR and 218 Volume 26, Number 3

4 Kendrick, Baxi, and Smith/JOURNAL OF EMERGENCY NURSING Figure 3 The response to therapy measured by the peak expiratory flow rate (PEFR) in the asthma and COPD group demonstrated that both groups had an increase in peak flow from pretreatment to posttreatment. No significant degree of change in the patients PEFR reading occurred when they were treated with a metered dose inhaler with spacer device (MDI) compared with a handheld nebulizer (NEB). Figure 4 The response to therapy measured by modified Borg scale (MBS) in the asthma and COPD group revealed that dyspnea scores decreased after respiratory treatments. No significant degree of change occurred in the patients MBS scores when they were treated with meter dose inhaler with spacer device (MDI) compared with a handheld nebulizer (NEB). SaO 2. Although subjective symptoms can be misleading, we hypothesized that a subjective component of pulmonary function exists that can be measured, and we believed that the principle of self-rating to describe the degree of dyspnea could be an important link in quantifying the complex feeling of being short of breath or having dyspnea in the acute environment. To determine the effectiveness of the MBS, we asked 2 questions: (1) Can patients with acute bronchospastic asthma or COPD adequately communicate their level of dyspnea using the MBS? (2) Does subjective improvement in the patient s breathlessness using the MBS correlate with improvements in pulmonary function as measured by the peak flow meter and SaO 2? Methods This retrospective chart review study was conducted at the emergency department and urgent care clinic at the VA San Diego Health Care System in San Diego, Calif. The MBS was added to the clinical protocol for management of patients with acute bronchospasm (Figure 2). According to the protocol, the MBS was administered by the triage nurse and again 30 minutes after respiratory treatments. The MBS procedure was explained to patients by the triage nurse and recorded as a fraction (patients rating number over the total possible; for example, 5/10). An attending physician evaluated all patients and ordered β 2 -agonist albuterol with anticholinergic agent ipratropium bromide delivered by either metered dose inhaler (MDI) with a spacer device or a handheld nebulizer (NEB). Patients with a complaint of dyspnea were selected based on review of the ED log. Among those with dyspnea, patients who met the following criteria were included in this study: (1) they had a history of asthma or COPD and were not oxygen dependent, (2) they received emergent treatment for bronchospasm and were diagnosed with either asthma or COPD, and (3) they were discharged from the emergency department to home after receiving treatment. Demographic information was limited to age and gender. A 3- way analysis of variance was used to examine the effect of diagnosis, treatment modality, and time on MBS, PEFR, and SaO 2. Next we examined the relationships between the change in PEFR readings and the change in MBS scores with treatment. We also examined whether there was a change in SaO 2 percentage and a change in MBS scores, which were analyzed by linear regression using the Pearson correlation coefficient (r). Changes were considered to be significant when P was less than.05. To describe the prescores and postscores (change scores), we looked at the relationship between the intensity of breathlessness scores June

5 JOURNAL OF EMERGENCY NURSING/Kendrick, Baxi, and Smith 199), bronchitis (n = 29), congestive heart failure (n = 33), and pneumonia (n = 37). Participants were all men between the ages of 24 and 87 (mean age, 59 years). Forty-two patients were diagnosed with asthma and 60 had COPD. The attending ED physician evaluated all patients after they were triaged and ordered β 2 -agonist albuterol with ipratropium bromide delivered by either a handheld nebulizer or a metered dose inhaler through a spacer device according to the protocol (Figure 2). Figure 5 The response to therapy measured by cutaneous oxygen saturation (SaO 2 ) in the asthma and COPD group increased from before to after respiratory treatment. A greater increase in SaO 2 occurred in the COPD than in the asthma group; concurrently, the post COPD group had slightly higher SaO 2 percentages when using a handheld nebulizer (NEB) than when using a metered dose inhaler with spacer device (MDI). and PEFR and between breathlessness scores and SaO 2 readings before and after therapy. Data are presented as mean ± SEM. Triage Patients who had a chief complaint of being short of breath or of experiencing dyspnea were shown an enlarged copy of the MBS and were asked to rate their dyspnea (Figure 1). Documentation on the ED record by the triage nurse included the following: PEFR, personal best peak flow if known by the patient, SaO 2 in percentage, and MBS in fraction format with the patient rating listed over the maximum possible (eg, 5/10). Respiratory narratives were optional and left to the discretion of the individual triage nurse. If the patient had a known history of asthma or COPD, a copy of the protocol for management of patients with acute bronchospasm was attached to the ED record (Figure 2). All 102 patients who met inclusion criteria were able to communicate their level of dyspnea to the triage nurse using the enlarged MBS. Reassessment by the primary care nurse was also easily and uniformly accomplished using the aforementioned method following postrespiratory treatment. Results Of the 400 charts initially selected for complaint of dyspnea, 102 patients met the inclusion criteria. The patients who were excluded had diagnoses of flu (n = Response to therapy As expected by the pathophysiology of the underlying illness, analysis of variances revealed a greater effect of treatment on pulmonary function as assessed by PEFR in patients with asthma compared with those who had COPD (P <.0001). As has been suggested in other studies, there was no significant difference in the degree of change in the patients PEFR when treated with a handheld nebulizer compared with a metered-dose inhaler using a spacer device in either the asthma or COPD group (P =.24) (Figure 3). Dyspnea improved, as measured by a decrease in MBS from triage to discharge in both the asthma and COPD groups. This improvement was found to correlate well with the increase in overall PEFR (r = -0.42, P <.0001) (Figure 4). Again, the method of respiratory treatment (MDI with a spacer device versus handheld NEB) did not affect the magnitude of the change in MBS in either patient group (P =.29). Oxygen saturation increased with treatment in both the asthma group and the COPD group (P <.0001). A significantly greater increase in SaO 2 was found in the COPD group than in the asthma group (P =.0438); this greater increase in SaO 2 is attributed to the fact that the COPD group started at a lower percentage. It is interesting to note that the benefit of NEB over MDI using a spacer device was not found to be significant in either the asthma or COPD group (P =.1495) (Figure 5). Pearson correlation in the asthma group In the asthma patient group, the mean MBS rating decreased from 5.1 at baseline to 2.4 after treatment. The mean PEFR increased from 286 at baseline to 414 after treatment, and the mean SaO 2 increased minimally (from 95% to 96%). In the asthma group, there was a significant negative correlation between change score in MBS and change scores in the PEFR from prescores to postscores (r =.31, P <.05). As the peak flow score increased, the MBS score decreased; thus the better the patients peak flow scores, the lower the patients dyspnea ratings. Similarly, there was a significant negative correlation between change in scores in MBS and the 220 Volume 26, Number 3

6 Kendrick, Baxi, and Smith/JOURNAL OF EMERGENCY NURSING change in pulse oximetry readings (r =.26, P <.05). As the MBS score decreased, the SaO 2 increased. Pearson correlation in the COPD group In the COPD group, the mean MBS decreased from 6.0 at baseline to 3.0 after treatment. Over the same interval, the mean PEFR increased from 183 to 252 and the mean oxygen saturation increased from 92% to 94% on room air. In the COPD group, there was a significant negative correlation between the change scores in MBS and change in PEFR from prescores to postscores (r =.42, P <.001). However, there was no correlation between change in MBS and the change in SaO 2 readings (r =.10, P <.30) in the COPD group. This finding was attributed to the fact that members of the COPD group were in varying states of hypoxia when oxygen saturation readings were taken. An interesting finding was that in the COPD group oxygen saturation was slightly higher after nebulizer treatment than with MDI treatment with a spacer device (Figure 5). We offer no explanation for this finding other than to report it. Discussion Our data suggest that the MBS can be used in the emergency department as an accurate tool to measure subjective dyspnea in patients with acute bronchospasm. In addition, we demonstrated that it correlated well with other clinical parameters often used in the emergency department. An unintentional discovery in this study was that the type of respiratory treatment prescribed by the physician(s) did not influence the patients subjective rating of dyspnea. This fact further strengthened our belief that patient-rating tools could be a good indicator, regardless of the treatment used. Most emergency departments are continuing to look for means to quickly assess and deliver rapid treatment to patients with respiratory problems. However, unless a patient is exhibiting acute respiratory distress, we have no sliding scale for early recognition that the patient will need a treatment in X period of time after they arrive in the emergency department. Therefore, should not triage nurses use all the tools at their disposal, including the patient as an indicator? Our study has had the following results: We have taken the information learned from this study and have incorporated the MBS into our practice in the emergency department and urgent care clinic. We now use the MBS as a part of triage assessment. This information provides baseline data to measure the effectiveness of treatment(s). We use the MBS to triage patients with respiratory complaints and have found it to be especially useful in patients who are too dyspneic to perform objective testing such as peak flow. We found that the MBS is effective in assessing and monitoring treatments in both the nonacute and the acute environment. This has been a practical and effective way to provide documentation and continuity of care information between the two areas. We teach both patients and medical staff to use the MBS. It has provided a common language to describe the subjective sensation called dyspnea in measurable terms. We have also found the MBS to be useful in assessing patients with other acute or chronic medical problems (eg, congestive heart failure, pneumothorax, pneumonia, lung cancer, and/or chronic bronchitis). Our Telephone Advice nurses have found the MBS to be a valuable tool when interviewing and evaluating respiratory problems by phone. The Hospital Home Based Primary Care nursing staff have found the MBS to be an important adjunct tool when assessing patients with respiratory problems in their homes. In many cases, these homebound patients are unable to give an adequate peak expiratory effort to measure their PEFR, and portable cutaneous oxygen saturation devices are not usually available. Many of our ED attending physicians use the MBS baseline data obtained at the time of triage to assist in decision making regarding whether to continue respiratory treatment; these data are also used to make a decision about whether to discharge or admit the patient. Poststudy feedback Patients gave the MBS tool a high satisfaction rating on ease of use. They reported that the language used in the scale adequately expressed their dyspnea. Discharged ED and urgent care clinic patients were also given a laminated, wallet-sized copy of the MBS to use on return visits. The emergency triage and primary care nursing staff rated the MBS highly satisfactory and found it quick and easy to use. Triage respiratory assessment notes and nursing notes were streamlined to include primarily the PEFR, MBS, and SaO 2. Time-consuming and detailed respiratory narratives were found to be unnecessary in most cases. The triage nurse and primary nurses also indicated that adding the MBS to the triage notes added another dimension when evaluating the level of acuity and/or treatment needs for each patient. June

7 JOURNAL OF EMERGENCY NURSING/Kendrick, Baxi, and Smith We are also looking into a means of adopting the use of the initials MBS to document dyspnea. We believe that MBS could be easily integrated into hospitals and clinics as an accepted abbreviation. Conclusion This study was limited to a relatively small group of adult men with bronchospasm who were treated and released from an emergency department or urgent care clinic. An expanded study with a general population might reveal even higher correlation scores and could generate valuable outcome measures that could have a positive impact on how we assess, treat, and document the common sensory description of having dyspnea or shortness of breath. We believe that the MBS can be an invaluable clinical indicator for patients whose respiration is compromised. Today, health care models are incorporating tools that measure or evaluate outcome-based care. Nield and Patel 2 thought that respiratory tools can play an important role in maximizing positive outcomes from therapy. Using outcome-based measurements to guide health care delivery is spreading throughout the field of medicine, and most emergency departments are streamlining their protocols and treatment plans to reflect outcome-based care. Therefore, building on the standard of our nursing practice compels us to seek out tools that can measure and improve care. By incorporating the principles of self-rating, the patient is able to contribute valuable information to the medical and nursing treatment plan. Acknowledgment We thank Marty Shively, RN, PhD, for her endless support and encouragement. References 1. Elliott MW, Adams L, Cockcroft A, Macrae KD, Murrhy K, Guz A. The language of breathlessness. Am Rev Respir Dis 1991;144: Nield M, Kim MJ, Patel M. Use of magnitude estimation for estimating the parameters of dyspnea. Nurs Res 1989;38: Borg G. Psychophysical bases of perceived exertion. Med Sci Sports Exerc 1982;14: Corbin AL. The patient with bronchospasm: assessment, triage, and teaching adjuncts. J Emerg Nurs 1992;18: Stromborg MF. Instruments of clinical nursing research. Boston: Jones & Bartlett Publishers; p National Asthma Education and Prevention Program. Expert Panel Report 2: Guidelines for the diagnosis and management of asthma (NIH publication A). Washington: National Institutes of Health; Mahler D, Wells C. Evaluation of clinical methods for rating dyspnea. Chest 1988;93: Harris D, Booker H, Rehaln M, Collins J. Measurement and perception of disability in chronic airways obstruction. Am Rev Respir Dis 1983;127(Suppl): Burdon JGW, Juniper EF, Killian KJ, Hargrave FE, Campbell EJM. The perception of breathlessness in asthma. Am Rev Respir Dis 1982;126: Belman MJ, Brooks LR, Ross DJ, Mohsenifar Z. Variability of breathlessness measurement in patients with chronic obstructive pulmonary disease. Chest 1991;99: Simon PM, Schwartzstein RM, Weiss JW, Lahive K, Fencl V, Teghtsoonian M, et al. Distinguishable sensation of breathlessness induced in normal volunteers. Am Rev Respir Dis 1989;140: Mador MJ, Rodis A, Magalang UJ. Reproducibility of Borg scale measurements of dyspnea during exercise in patients with COPD. Chest 1995;107: Wilson RC, Jones PW. A comparison of the visual analogue scale and modified Borg scale for the measurement of dyspnea during exercise. Clin Sci 1989;76: Volume 26, Number 3