Non-medical devices for chronic breathlessness: use, barriers and facilitators for patients, carers and clinicians - a scoping review

Background Non-medical devices such as the handheld fan (fan), mobility aids (wheeled walkers with seats) and inspiratory muscle training (IMT) devices offer benefits for patient management of chronic breathlessness. We examined the published evidence regarding patient, carer and clinician use of the fan, mobility aids and IMT devices for chronic breathlessness management, and the potential barriers and facilitators to day-to-day use in a range of settings. Methods MEDLINE, Embase, Scopus, EBSCO and the Cochrane Database of Systematic Reviews were searched. Papers were imported into EndNote and Rayyan for review against a priori eligibility criteria. Outcome data relevant to use were extracted and categorised as potential barriers and facilitators, and a narrative synthesis exploring reasons for similarities and differences conducted. Results Seven studies met the inclusion criteria (n=5 fan, n=2 mobility aids and n=0 IMT devices). All of the studies presented patient use of non-medical devices only. Patients found the fan easy to use at home. Mobility aids were used mainly for outdoor activities. Outdoor use for both devices were associated with embarrassment. Key barriers included: appearance; credibility; self-stigma; technical specifications. Common facilitators were ease of use, clinical benefit and feeling safe with the device. Conclusion The efforts of patients, carers and clinicians to adopt and use non-medical devices for the management of chronic breathlessness is impeded by lack of implementation research. Future research should improve knowledge of the barriers and facilitators to use. This would enhance understanding of how decision-making in patient–carer–clinician triads impacts on non-medical devices use for breathlessness management.


INTRODUCTION
People with progressive malignancy, cardiorespiratory and neurological conditions frequently experience disabling chronic breathlessness that seriously affects daily life despite optimum treatment of their underlying disease. 1 Limitations extend beyond the physical to social roles, emotional burden and functional impairment. 2 This frightening symptom is difficult to manage for patients, carers and clinicians. [3][4][5] Multidisciplinary 'breathlessness services' incorporating nonpharmacological interventions reduce the impact of the symptom, improve quality of life and promote self-efficacy. [6][7][8] Nonpharmacological interventions often support the patients' self-management of chronic breathlessness 7 and include non-medical devices such as the handheld battery-operated fan (fan), mobility aids and inspiratory muscle training (IMT) devices.

Review
A growing evidence base supports the use of cool facial airflow from a fan, both to reduce the sensation of breathlessness and to help self-efficacy. [9][10][11][12] Despite fan efficacy studies as early as 1987, 13 the mechanism of action is only partially understood. Stimulation of the lower branches of the trigeminal nerve, the nasal and upper airway flow receptors is thought to modulate central afferent respiratory centres, leading to decreased neural respiratory drive, and thereby also the perceived sensation of breathlessness. [13][14][15][16] Preliminary work also indicates that the fan can shorten recovery times from exertion-related breathlessness 11 17 and encourage increased physical activity 17 and less reliance on inhaled beta-agonists. 10 17 Wheeled mobility aids reduce breathlessness and increase walking distances. 18 19 Only wheeled walking frames are considered suitable for breathless patients, as the repeated upper arm elevation otherwise required incurs extra metabolic and ventilatory effort. 20 The forward lean posture and shoulder girdle support are thought to help respiratory muscles increase maximal force generating capacity 19 and thereby improving the efficiency of walking. 18 In addition, if the device provides a seat allowing breathlessness recovery, this may increase their selfconfidence to manage breathlessness particularly outside of the home. 21 A recent systematic review and meta-analysis of people with chronic obstructive pulmonary disease (COPD) found that using IMT devices decreases breathlessness and improves inspiratory muscle strength, exercise capacity and quality of life. 22 Its mechanisms of action are poorly understood, but may involve increased diaphragmatic strength and neural adaptations that facilitate the ability to recruit motor units during maximal voluntary activation of the diaphragm, thus lowering the load-capacity imbalance and perception of breathlessness during activity. 23 Despite review evidence, 8 22 24 25 demonstrating the effectiveness of various non-pharmacological interventions such as the fan, (including when delivered as a complex intervention) for the management of breathlessness, there are no reviews that explore implementation. Therefore, little is known about how this evidence-base leads to changes in care (implementation), how those changes become part of everyday practice (embedded) and sustained over time (integrated). Little is also known about the experiences of those who use or recommend the fan, IMT devices and mobility aids for the management of chronic breathlessness.
We aimed to examine the published evidence about patient, carer and clinician use of the fan, mobility aids and IMT devices for the management of chronic breathlessness, and to identify the potential barriers and facilitators to day-to-day use in a range of settings.

Research questions
► How are non-medical devices (fan, mobility aids, IMT devices) used for the management of chronic breathlessness by patients, carers and clinicians? ► What are the potential barriers and facilitators for patients, carers and clinicians to the use of these non-medical devices for the management of chronic breathlessness?

METHODS
The scoping review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Scoping Reviews checklist extension. 26 We used an exploratory approach in which data extracted about the day-to-day use of non-medical devices were interpreted, summarised and classified by the authors to identify the potential barriers and facilitators that may influence patient, carer and clinician use of these devices for chronic breathlessness.

Study eligibility criteria
The eligibility criteria are reported in table 1.

Data sources and searches
A protocol was created and is available on request. ASP searched the following databases: MEDLINE, Embase, Scopus, EBSCO and the Cochrane Database of Systematic Reviews (inception to June 2020). The search strategy was developed from a previous Cochrane review protocol (Respiratory interventions for breathlessness in adults with advanced diseases 27 ) for MEDLINE and then adapted for the other databases. The searches were conducted during April to June 2020 and combined keywords and indexing terms where appropriate based on PEO (Population, Exposure, Outcome). Individual searches were performed for each search component in combination In addition, each individual search for each population (patient, carer and clinicians) and exposure were conducted in combination with keywords relating to breathlessness without the outcome component to improve sensitivity. Terms for patients included each of the diseases of interest.
Different terms were used to describe each of the non-medical devices to ensure the inclusion of all relevant papers. For the IMT device searches, further keywords relating to respiratory therapy were added to the search. The term 'complex intervention' was included to capture fan, mobility aid or IMT use, if the results for the non-medical devices were reported separately from the other components of the complex intervention (see online supplemental file 1; search strategy and terms).

Review
The search strategy did not include filters for date or study design. Filters for English language and full-text articles were used.

Study selection
The results of the searches were imported into EndNote and Rayyan and reviewed against the screening tool checklist, developed for the inclusion of studies, by two independent reviewers (ASP and GIL). Full papers were retrieved and screened where insufficient information was presented in the abstract to enable a decision. Any disagreements or queries for inclusion were resolved by consensus with recourse to FS as a third reviewer.

Data extraction
Data extraction was conducted by ASP with support from FS using a bespoke extraction sheet. Data were extracted on study design, participant characteristics, intervention details, method, data type and outcomes relevant to device use.

Analysis
ASP and FS interpreted and categorised the potential barriers and facilitators to non-medical device use from the outcome data extracted. A narrative approach to synthesis was used wherein ASP and FS compared and contrasted the barriers and facilitators identified in the different studies, systematically exploring any reasons for these discernible from the results. 28

RESULTS
A total of 5837 individual papers were identified from the searches. On title/abstract review, 5739 were excluded due to irrelevant content. After de-duplication, 41 full-texts were assessed for eligibility and 7 were included in the review (see figure 1). 29 The non-medical devices used was the fan in five studies 9-12 17 and mobility aids in two studies. 30 31 We decided to include two secondary analyses studies 10 17 in addition to the two primary papers included in the review as it permitted inclusion of fan data not published in the primary papers 11 12 and report an in-depth exploration of the benefits and factors associated with fan use. 10 None of the included studies investigated IMT; an IMT study that was initially included was later excluded due to too few data on the experience and use of the IMT device. 32 Similarly, none of the studies that tested a complex intervention such as the Breathlessness Intervention Service (BIS) studies 7 33 were Guidelines. Reviews. Opinion pieces.

Population
(1) Patients; adults with chronic breathlessness due to cardiorespiratory and neurological disease (chronic obstructive pulmonary disease, lung cancer, interstitial lung disease, chronic heart failure, motor neuron disease). Studies that included a broader range of conditions were included if the majority of participants were living with a cardiorespiratory or neurological disease.
(2) Mobility aids (three or four wheeled walker or rollator with or without a seat).
(4) 'Complex interventions'-which include any of the non-medical devices above as part of their management strategy if reported separately from the other components.
Context of exposure: (1) Patients and carers-use/experience of non-medical device(s) for the management of chronic breathlessness at home and outside in the community, eg, shopping.
(2) Clinicians-use/experience of non-medical device(s) for patient management of chronic breathlessness in the community, primary and secondary care; hospitals including Specialist Palliative Care Units,eg, hospice.
Spacers as a non-medical device due to a high prevalence of studies in the paediatric population.

Outcome
Quantitative or qualitative data regarding non-medical device use, and/or potential barriers and facilitators to use for the management of chronic breathlessness.
Review included due to the lack of data reported on the individual non-medical devices. All studies were regarding patient perceptions with none studying clinicians or carers, if carers were included in the study there were very few data on their experience or use of the devices.

Characteristics of included studies
See table 2 for characteristics of included studies.

Patient characteristics
In the intervention arm, the five fan studies recruited a mixed population with chronic breathlessness due to different types of diseases, including COPD (n=155), malignancy (n=75), heart failure (n=3), pulmonary fibrosis (n=6) and other causes (n=54). 9-12 17 Five patients in one study were described as having more than one cause of chronic breathlessness. 17 Both mobility aid studies recruited patients with COPD (n=58). 30 31 One study focused on moderateto-severe COPD. 31

Intervention characteristics
All of the fan studies provided patients with standardised verbal and written fan use advice. 9-12 17 Patients were given additional guidance on exercise and techniques for breathlessness management in two studies. 11 12 The length of intervention was 28 days in four studies, 10-12 17 and 6 months in one study. 9 The length of mobility aid intervention and follow-up varied in the two studies; 8 weeks 31 and 7 days. 30 The intervention in both studies was the rollator walker (with seat) and the patient population was previous mobility aid users. 30 31 One study requested patients to integrate the mobility aid into their daily life. 31

Outcome data
Four of the fan studies provided qualitative data [9][10][11][12] ; two studies conducted semi-structured interviews after day 28 regarding fan experience and use 11 12 while one study was a secondary analysis of 133 interviews from three RCTs and included both a quantitative and qualitative analysis of the data. 10 The remaining fan study presented qualitative data from an initial patient interview and quantitative results from follow-up questionnaires used over 6 months. 9 One study presented quantitative data only; a survey of fan use completed after 28 days from two RCTs. 17 None of the included fan studies were designed using implementation science methods to explore implementation as a primary outcome. 9-12 17 All the fan studies presented outcome data on fan use at home from a patient perspective, 9-12 17 with no studies presenting the carer or clinician perspective.
Luckett et al 10 presented data of a secondary analysis of three RCTs and explored factors associated with fan use, its analysis cannot be extracted from the individual studies, such as the data of the BIS, 7 thus it was included due to the usefulness of the analysis.
Both mobility aid studies presented various quantitative outcome data. 30 31 Gupta et al, 31 requested patients to complete a diary of rollator use over 8 weeks, that included the activities for which the device was used. At the end of the study (8 weeks) a standardised questionnaire was used to tabulate the number and percentage of participants agreeing with specific statements pertaining to the rollator. 31 Hill et al 30 presented data from an interview based on the Structured Rollator Utility Questionnaire, the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST) and general satisfaction of rollator use.
None of the mobility aid studies were designed using implementation science with implementation as a primary objective. 30 31 Both of the studies presented data from a patient perspective only with mobility  Review aid use and experience from the context of home use during a 7-day observational study 30 and an 8-week RCT. 31

Use of non-medical devices
Non-medical devices use and potential facilitators and barriers to use (see online supplemental file 2; table 3).

Fan use
There was substantial variability in the way the fan was used in practice by the patients in terms of the timing, frequency, duration and location of fan use. The timing of fan use was between 1-10 min 9 10 with 4-5 min being the most common duration 10 and used 4-5 times a day. 10 17 Three-quarters (75%-76%) of patients used the fan at least one time per day over a 28-day study period 11 17 and people with COPD were more likely to use the fan every day; 61% (n=19) than other patients 39% (n=12) (OR 5.94 (CI 0.63 to 56.21) p=0.017). 17 In the one study with longer-term follow-up, fan use dropped to 40% (n=16/33) after 2 months with only nine patients still using the fan daily and seven patients using it occasionally. 9 Fan use over 28 days was tailored to individual preferences and the patients' daily routine. 11 17 It was used early in the morning or during the evening 17 and was incorporated with exercise advice as part of a complex intervention to self-manage breathlessness. 12 The fan was used before, during and as part of recovery from exertion, as well as a routine prophylactic measure and for acute episodes of breathlessness. 10 12 The fan was also used as a replacement or adjunct to beta-agonist inhalers [10][11][12] and was considered a first-line strategy to reduce breathlessness. 10 One study included table top fans in the analysis, which were placed in different locations where most likely needed. 10 Patients perceived the fan as a helpful device 9 that reduced recovery time from exertional breathlessness 10-12 and supported them staying active. 17 One study reported that carers had similar perceptions of the fan to patient-participants, but no data were presented. 10

Barriers to fan use
Two of the fan studies identified potential barriers to fan use 9 10 but three studies reported none. 11 12 17 Some patients struggled to believe that the fan could be a clinical intervention, 9 10 commenting that it looked like a toy. 9 Some patients were less likely to use the fan outside as they were concerned about attracting unwanted attention, especially in the winter months. 10 Sensitivity or irritation by the cold airflow, 9 particularly in winter, as well as concerns about breathing dust if the fan was not cleaned properly were cited as issues preventing use. 10 Technical barriers revolved around the inability to vary airflow rate to suit individual need, 10 reliability 9 and robustness of the fan, the level of noise, the safety of the blades and operability issues, such as difficulty with battery changes and the need for patients to use their hands to hold and operate the fan. 10

Facilitators to fan use
Facilitators to fan use were identified in all five studies. 9-12 17 In general, fans were acceptable to patients, and the device seen as a helpful management strategy for breathlessness [9][10][11][12] which could be readily integrated into and support daily activities. 11 12 The ease of use 10 and the portability allowed patients to tailor to individual needs [10][11][12] in different contexts. 10 12 Perceived benefits along with a lack of side-effects 10 12 were strong drivers of fan use such as reduced recovery time from exertional breathlessness 10-12 and increased activity. 17 The improved confidence to manage breathlessness 10-12 allowed patients to reclaim control 12 and promoted independence. 10 Regular fan use was identified as 'making life easier'. 9 The possibility of a nonpharmacological alternative replacement for inhalers or oxygen was welcomed by patients. [10][11][12]

Mobility aid use
The mean duration of rollator use in patients who already used the device over 8 weeks was 26±4 (range 5-60) days. 31 Two different types of mobility aid users were identified; frequent users, patients who used the rollator at least three times a week and infrequent users, patients who used the mobility aid less than three times a week. Frequent users (n=10) reported rollator use range 25-60 days and infrequent users (n=8) range 5-15 days over 8 weeks. 31 Hill et al 30 reported 59% daily rollator use in patients who already used the device over 7 days, with 30% using the device at least once a week and 11% using the rollator less than once a month. 30 The activities and reasons for rollator use varied with all patients, 100% (n=27), 30 or most 81% (n=13) 31 reporting rollator use for outdoor walking, or activities outside of the home such as recreation and shopping. Patients reported least rollator use walking inside the home; 30% (n=8) 30 to 31% (n=5), 31 and doing activities inside the home 6% (n=1) 31 to 30% (n=8). 30 Other activities that the rollator was used for included; transition from inside to outside the home; 31% (n=5) 31 to 50% (n=14), 30 getting to and from the car; 38% (n=6) 31 to 60% (n=16), 30 and walking indoors, but not at home; 81% (n=13) 31 to 90% (n=24) 30 or activities not at home 63% (n=10). 31 Patients also reported that they appreciated the seat (86%) and felt less breathless (71%) with rollator use. 31 Neither study reported any carer data or details of how mobility aid us related specifically to the management of breathlessness.

Barriers to mobility aid use
Although most patients preferred the rollator, nearly half (n=8/18) used it fewer than three times a week. 31

Review
Indoor rollator use in particular was associated with problems such that 59%, (n=16) did not use the device inside the home, although some found it helpful to support other daily activities of living such as washing and dressing, bending and carrying. Patients felt it was too bulky, they had difficulty pushing the device across floor coverings or they were unable to use it due to the stairs. 30 In addition, less than half (41%) of women were able to lift the device in and out of a car compared with 80% of men. 30 Embarrassment also featured as barrier to rollator use outside with 48% (n=13). 30 In addition, while 31% (n=4) of patients felt they were only embarrassed for the first few weeks, 69% (n=9) reported persistent embarrassment. 30

Facilitators to mobility aid use
As with the fan, perceived benefits encouraged use. All of the patients (100%, n=45) felt improved exercise endurance and reported feeling safe and stable using the rollator. 30 31 In addition, 71% (n=32) reported decreased breathlessness with rollator use and improvements in quality of life were noted in both frequent (86%, n=9) and infrequent (91%, n=7) rollator users. 31 There was high patient satisfaction with the rollator according to QUEST. 30 This indicates that rollator specifications met the needs of the patient in terms of mobility device dimension, comfort, effectiveness, safety, security and ease of use and adjustment, despite the weight that hindered device use for women 30

DISCUSSION
This scoping review draws together the available evidence for the use of non-medical devices for the management of chronic breathlessness. Seven papers met the scoping review criteria; five fan (n=327) and two mobility aid (n=58) studies.
We found that patients associate fan and mobility aid use with relief of breathlessness, improved exercise capacity 11 17 31 and confidence. 9 11 12 30 31 The fan was readily integrated into patients' breathlessness management and was easily tailored to daily needs around the home and different breathlessness situations. [10][11][12] In contrast, mobility aids were mainly used for breathlessness management with outdoor activities. Barriers around the home, such as bulk and weight reduced the usefulness of the device for breathlessness management indoors, instead patients used the mobility aid to help with other daily activities of living such as washing and dressing. 30 31 However, both fan and mobility aid use in public places were associated with embarrassment 30 and could attract unwanted attention. 10 It is possible that illness perception, that is, the patient's beliefs about the health threats posed by their illness which form the cognitive basis for their adaptive coping responses, 34 35 may influence non-medical device use outside. In people with COPD, high illness perception scores in relation to how they evaluate living with their disease are associated with more breathlessness, 34 poorer ability to cope with symptom management and reduced patients' quality of life. 36 37 In addition, stigma is already established as a reason to deter patients from using a mobility aid. 38 39 This is important as a high illness perception score coupled with the stigma felt from device use outside may prevent patients using these interventions and limit any breathlessness benefits to activities inside the home.
The current commercial design of the fan may also act as a barrier to device use in public. Patients were sceptical of the intervention 9 10 and, other problems such as the operability, safety of the blades, noise, robustness, difficulty with battery change and the lack of airflow rate variability were all highlighted as potential issues that could compromise use. 10 These concerns may explain the results of a longitudinal study which reported a drop in adherence in fan use after 2 months, 9 and suggest that long-term maintenance of fan use for breathlessness management could be compromised by the appearance and technical specifications of the device.
In contrast the appearance of the mobility aid was not identified as a specific barrier to outdoor use. This may relate to public recognition of a non-medical device to support disability. It is possible that the embarrassment experienced by patients from using a mobility aid relates more to the visual signal that the person has an illness, rather than its appearance. Use outside was instead compromised by the lack of portability of the mobility aid in terms of weight and bulk.
This review provides valuable insights into patients' experiences and use of non-medical devices for the management of chronic breathlessness. It also highlights significant gaps in the research evidence about barriers and facilitators for patients, carers and clinicians to routine device use.
Despite broad population inclusion criteria, there were no directly reported data on carers' perspectives on non-medical device use. Carers have an important role in patients' breathlessness management 4 and are acknowledged as driving decisions about the prescription of oxygen., 40 therefore it is essential that future research considers the patient-carer dyad as a unit 4 to understand how carers may influence patient use of non-medical devices for chronic breathlessness.
Chronic breathlessness is recognised as a challenging symptom for clinicians to manage and is often a cause of communication difficulty leading to symptom 'invisibility' between clinicians and patients. 3 41 42 Yet, importantly, the way a clinician delivers an intervention is known to influence outcome. 43 However none of the included studies explored clinicians' perspectives and recommendation of non-medical device use for chronic breathlessness management. This information is crucial to understand as the clinicians' perception Review and delivery may represent a hidden barrier to patient use of non-medical devices for breathlessness management; a possible problem for the fan in particular given the commercial variability in appearance.
It is likely that the perception and credibility of nonmedical devices will vary widely across patients, carers and clinicians. Indeed given the tendency of some clinicians to assume a biomedical focus on disease, 44 it is possible that drug and surgical interventions are considered the default management with a higher cultural status, 21 while non-pharmacological interventions such as the fan are labelled as 'non-clinical activities' 21 ; a perception reflected by the review results as patients were sceptical about the credibility of the fan. 9 10 The review was unable to identify any studies that investigated the use of IMT devices. It is possible that IMT is overlooked as a usual component to include for the management of chronic breathlessness despite the commercial availability and low cost of the device. Given that evidence reports that these devices decrease breathlessness, improve inspiratory muscle strength, exercise capacity and quality of life, 22 the uptake and use of IMT devices should also be considered a priority to explore in future studies.
Finally, none of the included studies used an implementation science theory or framework to focus enquiry and enable findings to contribute to emerging interdisciplinary knowledge about implementation, 45 Given the Medical Research Council framework for complex intervention's 46 emphasis on the need for refinement and ongoing modelling in conjunction with testing in practice, an implementation theory or framework, for example, process evaluation 47 could provide a valuable structure to identify mediators and measure outcomes that inform optimisation of both intervention and implementation. Also, from the behavioural sciences, the Theoretical Domains Framework could be used to drive research into factors that impact on individuals' uptake of non-medical devices, their adoption into routine behaviour, and the maintenance of their use over time. 48 To extend research beyond the individual, a social science theory such as Normalisation Process Theory provides significant scope for investigating how the interactions of patient-carer-clinician triads impact on the implementation, embedding and integration of non-medical devices into complex social systems. 47 49 50 By extending the focus further to the level of a unit, organisation or system, a framework from the organisational sciences such as Promoting Action on Research in Health Services can structure research into the significant broader issues that impact on implementation. 51 52 If research into pain and symptom management is to learn from and contribute to interdisciplinary scientific understanding about implementation then, in common with research conducted in other fields, it must draw on implementation theory. 53

Strengths and limitations
The scoping review included both quantitative and qualitative data. The inclusion of the qualitative data allows for an in-depth exploration of the participant's perspective and enriches the results. We view our decision to include two secondary analyses as a strength as these studies 10 17 report unpublished and additional data as well as an in-depth qualitative analysis not included in the primary papers.
Strengths also include the blinding of the two independent reviewers during the full-text screening and the data extraction review by a second author which helps to reduce selection and information bias.
Limitations include the lack of quality appraisal of the included studies and the searches were limited to English language and full-text articles.

CONCLUSIONS
We found limited data on non-medical device use for the management of chronic breathlessness, all of which focused on the fan and mobility aids rather than IMT devices and the perspective of patients rather than carers or clinicians. None of the studies applied implementation science theory. The fan and mobility aids were identified as useful components of breathlessness management that were tailored to different patient activities. The fan was used around the home, whereas the mobility aid was suited mainly to outside activities. Patient use of the fan and mobility aid in public places was limited. Key barriers were the appearance, credibility of the device, self-stigma and the technical specifications. Common facilitators were ease of use and feeling safe and secure with the device.

Recommendations
Future research should be underpinned by implementation science theory or framework and must not only improve understanding of barriers and facilitators for patients, but also carers and clinicians. This would provide much needed data on how carers and clinicians perceive and use the interventions and help explore the interplay between patients', carers and clinicians' use of non-medical devices and ultimately if this influences the benefits for patient management of chronic breathlessness.

Implications for clinical practice
It is essential that clinicians consider not only the importance of the delivery of non-medical devices for breathlessness management, but the follow-up as well. How patients are using (or not using) non-medical devices for the self-management of breathlessness can be assessed easily by demonstrating its use rather than merely recommending it, asking about intervention use at routine appointments and raising awareness of these non-pharmacological interventions among the multidisciplinary team. This may serve to highlight potential problems that will compromise patient