An investigation into the immediate impact of breathlessness management on the breathless patient: randomised controlled trial

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1 Physiotherapy 91 (2005) An investigation into the immediate impact of breathlessness management on the breathless patient: randomised controlled trial Jennifer K. Hochstetter, Jeremy Lewis, Lorna Soares-Smith Therapy Department, Chelsea and Westminster NHS Healthcare Trust, 369 Fulham Road, London SW109NH, UK Abstract Objective Physiotherapy breathlessness management is considered to be a major component in the treatment of breathlessness; however, evidence of the efficacy of this practice is lacking. This clinical study aimed to identify the immediate impact of breathlessness intervention on perceived breathlessness. Design A pragmatic randomised controlled study. Setting Collection of data took place over a 4-month period within an in-patient setting in a National Health Service acute teaching hospital. Participants Thirty-one subjects participating in the study were recruited over 3 consecutive days and were randomly allocated to the intervention or control groups. Intervention Physiotherapy breathlessness management including pursed lip and diaphragmatic breathing, blow-as-you-go, positioning and pacing techniques were taught to the individuals in the intervention group on an individual basis during a 45-minute training session. Main outcome measure The Borg scale was the primary outcome measure. Measurements were taken before, during and after a stair climbing exercise. Results Data were collected from 30 subjects (mean age 75.2 years) with a variety of cardiopulmonary conditions. The results suggested that the intervention group reported a reduction in breathlessness during stair climbing (P = 0.02) and after descending the stairs (P = 0.02) following a session of breathlessness management. No change was observed in the control group. Conclusion The findings of the current investigation suggest that individuals with dyspnoea are able to incorporate techniques taught as part of a breathlessness management package of care, and that in the short term, these techniques have a positive effect on the perception of breathlessness. Future studies should look at the long-term benefit of these procedures Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved. Keywords: Borg Scale; Breathing control; Breathlessness; Physiotherapy management Introduction An increase in the effort or work of breathing is a sensation frequently experienced by those with cardiorespiratory conditions, and shortness of breath is a common symptom associated with restriction of pulmonary airflow [1]. Poor control of breathlessness or dyspnoea may impair function and have a detrimental effect on an individual s quality of life [2]. Individuals who are breathless have been encouraged to control their dyspnoea to improve function [3] and it is believed that breathlessness management can positively Corresponding author. Tel.: ; fax: addresses: jenny@hstraining.fslife.co.uk (J.K. Hochstetter), jeremy.lewis@chelwest.nhs.uk (J. Lewis). influence this by affecting breathing rate, lung volume and energy conservation [1] during exercise or functional activity. It is encouraging that pulmonary rehabilitation programmes have been shown to reduce dyspnoea, reduce the length of hospitalisation, and improve quality of life [4 6]. These interventions have been multi-modal and have included: relaxation classes, psychosocial intervention, inhaler techniques, nutritional advice, exercise drills and physiotherapy breathlessness management [7,8]. Physiotherapy breathlessness management has included: breathing control, positioning, and techniques to reduce unnecessary muscle activity [1,9 12]. Both diaphragmatic and pursed lip breathing have been shown to result in lower oxygen costs in individuals with chronic obstructive pulmonary disease [13], reducing the work of breathing. Education has also been advocated as an /$ see front matter 2004 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved. doi: /j.physio

2 J.K. Hochstetter et al. / Physiotherapy 91 (2005) important component in the management of breathlessness, increasing both confidence and awareness [1,11,13]. Dyspnoea is a subjective sensation and the adapted Borg scale is a tool that allows an individual to communicate their perception of breathlessness in a simple and practical manner [23]. It has been used to identify a level of breathlessness in individuals suffering from a wide range of pathologies, as well as in research investigating the efficacy of pulmonary and cardiac rehabilitation programmes [14 20]. The use of the adapted Borg scale has been reported to be reliable and valid [14 19,21,22]. Wilson and Jones [14] reported that the Borg scale was more reliable for measuring perceived breathlessness during exercise than a visual analogue scale. The National Institute for Clinical Excellence (NICE) in 2004 [7] stated that individuals with chronic obstructive pulmonary disease commonly experience breathlessness and this impacts negatively on their activities of daily living, such as stair climbing. Guidelines produced by NICE [7] state that respiratory physiotherapy is a specialised area of care with three main aims: (i) to reduce the work of breathing associated with respiratory disease, (ii) to help restore maximal function, and (iii) to help improve peripheral and respiratory muscle weakness. Increasing physical activity has been suggested as a method to improve quality of life in individuals with chronic obstructive pulmonary disease [24,25], and others have recommended that increased physical activity should be combined with physiotherapy breathlessness management [11,12]. Although physiotherapy breathlessness management is considered to be a major component in the management of the breathless patient as an intervention to improve functional performance, research evidence investigating its efficacy as a sole intervention is lacking. The aim of this study was to investigate the immediate effect of this management on breathlessness during the functional activity of stair climbing. Method Design A pragmatic randomised, controlled repeated measures study was performed to investigate the immediate effects of breathlessness management on perceived breathlessness. Data collection took place over 4 months in a National Health Service acute teaching hospital. Participants The participants in this study were in-patients suffering from cardiovascular, palliative, surgical or respiratory pathology. They were referred by medical staff, nurse specialists and physiotherapists working on the medical and surgical wards of the hospital. The Adapted Functional Abilities Questionnaire [11] was administered to all potential subjects, and those describing an increase in breathlessness during stair climbing fulfilled the inclusion criteria. As the subject population included elderly patients who may experience reduced memory attention, the Abbreviated Mental Test (AMT) was also completed to assess the individual s level of cognition [26]. Antonelli Incalzi et al. [27] have stated that an AMT score greater than six reliably rules out dementia. This instrument aims to screen subjects for mental deterioration and to ensure a study population with a normal level of attention and memory. Inclusion and exclusion criteria The inclusion criteria included: subjective reporting of shortness of breath during stair climbing, an AMT score of greater than six, in-patient status for at least 3 consecutive days, able to fully communicate in English, and independently mobile with or without a walking stick. The exclusion criteria included: previous physiotherapy intervention for shortness of breath, resolution of shortness of breath due to medical intervention, being medically unstable, contraindications to stair climbing, and an individual standard distance score (refer to Procedure section) varying by more than two levels over the 3 days. Ethical considerations Individuals invited to participate in the study received a detailed information sheet and verbal explanation of the purpose of the study. Those willing to participate, who fulfilled the inclusion criteria and were not excluded, completed informed consent documents. Subjects were aware of their right to withdraw from the study at any stage of the intervention. Power analysis Lewis et al. [28] reported a standard deviation of 0.5 for the resting Borg score in 22 patients diagnosed with chronic obstructive pulmonary disease. Based on this, it was determined that the number of subjects required for a significance level of alpha = 0.05 and a power of 90% was 13 in each group [29]. This was increased to 15 per group in case of subject withdrawal from the study and any potential missing data. Statistical analysis Data analysis was performed using Statistical Package for the Social Sciences, version 12.0 software (SPSS, Woking, UK). The main outcome measure was the adapted Borg Scale which is an ordinal scale. Sim and Wright [29] have stated (p232) that the Sign test should be used for ordinal data in preference to the Wilcoxon signed-ranks test. Therefore, the Sign test and the two-tailed Mann Whitney U test were used in the statistical analysis. Due to the ordinal nature of the primary outcome measure, medians and inter-quartile ranges are reported. Statistical significance was set at the 5% level.

3 180 J.K. Hochstetter et al. / Physiotherapy 91 (2005) Procedure Subjects participating in the study were recruited for 3 consecutive days. Random number tables were used to allocate participants to the breathlessness intervention group or the control group. Individuals were recruited once they were referred, had time to read the information sheet and had the opportunity to ask questions relating to the investigation. Therefore, the number of days since hospital admission to the commencement of the study for each individual varied. Demographic data were recorded for each subject at the start of the investigation, including information on medication. Health professionals referring subjects were requested to recruit subjects who were medically stable and capable of performing the stair climbing exercise. During the data collection period, each subject s medical notes were reviewed daily to ensure that there was no substantial fluctuation in the individual s medical condition. In addition to this, and to reduce the potential confounding effect of an alteration in the subject s shortness of breath brought about by medication or natural variation in underlying pathology, both the intervention and the control group subjects walked an individual standard distance (S) and the Borg rating was recorded following this walk. Subjects who reported a change of two points or more in either direction from their baseline S score were withdrawn from the study. In this manner, it was hoped that the subject s baseline level of dyspnoea would remain consistent during the 3 days of data collection. Subjects in the experimental group were requested not to use the intervention techniques taught to control breathlessness during this walking test. The subjects were shown the Borg scale, which is a vertical visual analogue scale with verbal descriptors ranging from 1 at the top, which represents not breathless, to 10 at the bottom, which represents maximal breathlessness, on each occasion their perception of breathlessness was recorded. Standard prompts were given to each subject on each occasion that the Borg scale was used to ensure that the subjects remained familiar with the scale. The stair climbing procedure involved wheeling the subject to the base of a flight of stairs in a standard hospital wheelchair. There were 12 steps in total and each step was 16 cm in height. When positioned at the base of the stairs, each subject was asked to stand. After standing, the first Borg rating measurement was taken. This measurement was designated B1a (Borg measurement, day 1, base of stairs prior to ascent). Subjects were then requested to ascend the stairs. As soon as the subject had ascended the stairs, the second Borg rating was taken. This was designated B1b (Borg measurement, day 1, top of stairs). Patients were permitted to stop and rest at the top of the stairs if required. They were instructed not to talk and, when able, to descend the stairs. At the base of the stairs, the third Borg rating was taken. This was designated B1c (Borg measurement, day 1, base of stairs after descent). At this stage, the patient returned to the chair. Throughout the activity, the investigator recorded the number of stops during the ascent and descent in addition to any walking aid requirement. The same procedure was performed on the third day of the investigation. On this day, the Borg measurements taken were designated B3a (Borg measurement, day 3, base of stairs prior to ascent), B3b (Borg measurement, day 3, top of stairs) and B3c (Borg measurement, day 3, base of stairs after descent). The second day of the study involved subject education and rehabilitation for the subjects randomised to the experimental group. This involved providing breathlessness information in addition to demonstrating and practicing methods to reduce dyspnoea. Standard methods were taught to each patient within a 45-minute session which took place 24 hour prior to data collection on the stairs on day 3. Based on the current literature and clinical specialist advice to reduce and prevent dyspnoea [9,11,12], four main clinical procedures were identified as common practice in physiotherapy breathlessness management. These included: positioning, breathing techniques, energy conservation, and pacing. The positions used to reduce breathlessness were demonstrated in lying, sitting, standing and walking (Figs. 1 3). Once in these positions, breathing techniques were practised. Each subject was taught both diaphragmatic and pursed lip methods of breathing with the aim of reducing the subject s respiratory Fig. 1. Forward lean sitting.

4 J.K. Hochstetter et al. / Physiotherapy 91 (2005) Fig. 2. Side leaning and fixing shoulder girdle against wall. Fig. 3. Forward lean standing. rate and any overuse of accessory muscles. Techniques were then taught to prevent breathlessness. The importance of energy conservation during activities was explained and the skill blow-as-you-go was taught. This involved breaking up functional tasks into sections of movement in combination with patients synchronising expiration whilst performing each section of the task; for example, breathing out each time an ascent or descent of one step was made. Encouraging expiration during these activities aimed to facilitate, relaxation of the inspiratory muscles of respiration. This technique was demonstrated and practiced in three functional tasks: (i) during sitting to standing, (ii) reaching for an object, and (iii) ascending and descending a flight of stairs. Finally subjects were taught how to pace themselves when walking or stair climbing in order to control breathing. The physiological rationale underpinning the skills that were taught was explained to each subject during the practical session. Instructions on how to recognise signs and symptoms of breathlessness were emphasised. An education sheet was provided to each subject to reinforce the theoretical and practical information. The investigator met individually with the subjects in the control group in order to: (i) measure the S, and (ii) monitor the participant s medical status. These subjects were taught the same breathless intervention methods once the clinical data collection had been completed on the third day. Results Thirty-one patients who met the inclusion criteria were enrolled in the study. One subject in the intervention group was withdrawn after the second individual walking test (S) conducted on day 3, due to a decrease greater than two on the Borg scale. The control group consisted of 10 males and five females with a mean age of 76.9 years (S.D. = 15.4 years) and a mean AMT score of 9.3 (S.D. = 0.87, range 7 10). The experimental group consisted of seven males and eight females with a mean age of 74.3 years (S.D. = 15.6 years) and a mean AMT score of 8.5 (S.D. = 0.99, range 7 10) (Table 1). A respiratory origin of the breathlessness was identified in the majority (70%) of subjects, and almost half the population (40%) had underlying chronic obstructive respiratory disease (Table 2). The mean number of stops for the control group was 0.9 (range 0 5) for day 1 and 1.3 (range 0 6) for the final data collection (day 3). The corresponding results for the intervention group were 1.6 (range 0 6) for day 1 and 3.6 (range

5 182 J.K. Hochstetter et al. / Physiotherapy 91 (2005) Table 1 Subject characteristics of the control and intervention groups Control group Intervention group Mean S.D. Range Mean S.D. Range Age (years) Height (cm) Weight (kg) Peripheral oxygen saturation (%) Table 2 Descriptive data for the control and intervention groups Control group Intervention group Number Percentage Number Percentage Pathology Respiratory Cardiac Palliative Surgical Chronic obstructive pulmonary disease Yes No Oxygen requirements Yes No Smoker Yes Ex-smoker No Walking stick Yes No ) for day 3. These results suggest that during the final stair climbing activity, the intervention group paused on a greater number of occasions than the control group. The median Borg scores at the base of the stairs, at the top of the stairs after the ascent, and at the base of the stairs after the descent were the same for both groups on the first day of data collection (Table 3). The median score was the same for both groups at the base of the stairs prior to the ascent on day 3 of the data collection period. However, at the top of the stairs on day 3, the median Borg score was seven for the control group and five for the intervention group. At the base of the stairs after the descent on day 3, the median scores were seven and five for the control and intervention groups, respectively. These results suggest a lower perception of dyspnoea in the intervention group on day 3 during and after the stair climbing activity. The results suggest that there was no significant difference in the Borg scores between days 1 and 3 (Table 4)atthe base of the stairs prior to the ascent in either group. There were also no significant differences in Borg score at the top of the stairs or at the bottom of the stairs after the descent in the control group. In contrast, there was a significant difference at the top of the stairs between days 1 and 3, and at the bottom of the stairs after the descent in the intervention group. Furthermore, there was no significant difference in the number of stops in the control group between the two trials, whereas there was a significant difference for the intervention group. No significant differences were found in Borg scores between the groups at the base of the stairs before the ascent, at the top of the stairs, or at the base of the stairs after the descent for the first day of the investigation (Table 5). Neither was there a significant difference between the groups at the base of the stairs before the ascent on day 3 of the investigation. However, a significant difference was reported between the groups at the top of the stairs on day 3 and at the base of the stairs after the descent. There was also a significant difference between the groups for the number of stops on day 3. A box plot details the within and between group changes for the Borg scores at the various stages of the stair climbing activity over the data collection period (Fig. 4). Table 3 Borg scores at each data collection stage for the two data collection days for both groups Time point Control group Intervention group Median IR a Range Median IR a Range Day 1 B1a: base of stairs before ascent B1b: top of stairs after ascent B1c: base of stairs after descent Day 3 B3a: base of stairs before ascent B3b: top of stairs after ascent B3c: base of stairs after descent a Inter-quartile range.

6 J.K. Hochstetter et al. / Physiotherapy 91 (2005) Table 4 Results of comparison between the results for days 1 and 3 for control and treatment groups Variable Comparison Control group (P value a ) Treatment group (P value a ) Borg score Base of stairs prior to ascent, day 1 vs. day 3 (1a:3a) Top of stairs after ascent, day 1 vs. day 3 (1b:3b) Base of stairs after descent, day 1 vs. day 3 (1c:3c) Number of stops Day 1 vs. day a Sign test. Table 5 Results of comparison between control and treatment groups Time point Variable Mann Whitney U test (two-tailed) (P) Day 1 Borg scale Bottom of stairs prior to ascent Top of stairs after ascent Bottom of stairs after descent Number of stops Day 3 Borg scale Bottom of stairs prior to ascent Top of stairs after ascent Bottom of stairs after descent Number of stops Fig. 4. Box plot highlighting changes in perceived breathlessness (Borg score) at the different stages during stair climbing. Key: 1a: base of stairs prior to ascent, day 1; 1b: top of stairs after ascent, day 1; 1c: base of stairs after descent, day 1; 3a: base of stairs prior to ascent, day 3; 3b: top of stairs after ascent, day 3; 3c: base of stairs after descent, day 3. Discussion The findings of the current investigation suggest that one session of physiotherapy training has a significant effect on reducing a patient s level of perceived breathlessness. The baseline measurements (B1a, B3a and Borg S) taken on days 1 and 3 of the investigation suggested that the level of dyspnoea experienced by subjects in both the control and experimental groups remained stable during the data collection period. This suggested that the improvement in perceived breathlessness experienced during the stair climbing activity recorded for the subjects in the experimental group may be attributed to implementation of the breathlessness management training provided on day 2 of the investigation. The subjects participating in this study were drawn from an inpatient population in an acute hospital and the underlying causes of their breathlessness were varied. The findings of this investigation suggest that the techniques used to control

7 184 J.K. Hochstetter et al. / Physiotherapy 91 (2005) breathlessness were beneficial over this range of pathologies, and may be considered by clinicians as part of the short-term management of the breathless patient suffering from these pathologies. The combined mean age for the subjects in this study was 75.2 years, which reflects findings of epidemiological studies that suggest the elderly are prone to chronic breathlessness [30]. The findings of this study should only be extrapolated for this age group. Ascending and descending stairs are activities where breathlessness would be expected to worsen in people suffering from dyspnoea if breathing control intervention strategies are not implemented. One of the strategies that has been recommended [11] is pacing the activity and stopping when necessary. The subjects in the experimental group significantly increased the number of stops that they took on day 3 when ascending and descending the stairs, suggesting that the subjects utilised the advice given on day 2 to help control their breathlessness during stair climbing and descent. Using this strategy of stopping and pacing the activity to control breathlessness, it is hoped that this may allow the individual to perform more of that activity, which may potentially result in maintaining cardiovascular function during episodes of breathlessness. This is speculative and the prolonged effect of this strategy on cardiovascular function requires investigation, particularly because it cannot be assumed that an increase in the number of pauses taken by the intervention group was purely due to the introduction of new techniques; it is possible that these procedures had an unmeasured effect on the cardiovascular system. The breathlessness management approach used in this study included a number of techniques: positioning, pacing, pursed lip breathing, diaphragmatic breathing, advice, and the blow-as-you-go technique. The inclusion of this package of care appears to benefit subjects with dyspnoea in the short term. Although these findings support those of the American Thoracic Society [1], which recommend patient education as an essential component in managing breathlessness, the independent effect of each technique utilised in the current investigation is not available from the data analysis. This would be a worthwhile focus of future research. The Borg scale was developed as a method of communicating the individual and subjective sensation of breathlessness. It has been shown to be a reliable instrument, its use has been recommended extensively in clinical guidelines and it has been used widely in clinical research [31 35]. The aim of this pragmatic investigation was to add to the body of evidence required to determine the benefit of clinical procedures aimed at reducing breathlessness in individuals with dyspnoea. With this in mind, it was considered that the Borg scale would provide useful information to add to this knowledge base. It is noteworthy that a correlation between the perception of breathlessness and respiratory-metabolic factors associated with breathing has been reported [22]. It is acknowledged that the Borg scale represents only one of a number of psychophysical measuring methods [36]. It is also acknowledged that other parameters could have been included in the investigation such as respiratory rate, heart rate, oxygen saturation, vital capacity and minute volume. These measurements would have added to a better understanding of the physiological response to the intervention. However, they would not have added to the main aim of this investigation, that being the response of the intervention to the perception of breathlessness. In addition to this, NICE has produced guidelines which recommend that breathless individuals should be questioned about their ability to perform the activities of daily living and how breathless they become while performing these activities [7, p31], which reflects the primary aim of the current investigation. The time taken to ascend and descend the stairs was not recorded in this study. Booker [37] has questioned the value of timed functional measurements for breathless individuals and recommended investigating breathlessness management in a non-timed environment. The rationale for this is that Booker [37] reported that subjects appeared more concerned in completing the task in a reduced time, rather than implementing the strategies taught to control breathlessness. It was hoped that by relying on the individual subject s perception of breathlessness at each stage of data collection, a true reflection of the subject s breathlessness status was reported and used in the analysis of data. However, it is acknowledged that a major limitation of the current investigation is the lack of blinded assessment and this study would have benefited from an assessor blinded to group allocation. This was however beyond the financial constraints of this investigation and the inclusion of blinded assessment in future studies is strongly recommended. Conclusion Shortness of breath can detrimentally impact on the quality of an individual s life and reduce functional ability. Interventions aimed at reducing breathlessness have the potential to help the individual control breathing during episodes of breathlessness and during a functional activity where breathlessness impacts negatively on that activity. In previous investigations, physiotherapy breathlessness management as part of a pulmonary rehabilitation programme has been shown to be effective. The findings of the current investigation suggest that individuals with dyspnoea are able to incorporate techniques taught as part of a physiotherapy breathlessness management package of care, and that as a sole intervention, these techniques have a positive effect on the perception of breathlessness in the short term. Future studies should look at the long-term benefit of these procedures. Acknowledgements The authors would like to acknowledge the physiotherapists who assisted in this investigation.

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