Non-pharmacological interventions for breathlessness in people with cancer

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.

A Mixed Methods Evaluation of a Pilot Multidisciplinary Breathlessness Support Service

Breathlessness support services have demonstrated benefits for breathlessness mastery, quality of life and psychosocial outcomes for people living with breathlessness. However, these services have predominantly been implemented in hospital and home care contexts. This study aims to evaluate the adaptation and implementation of a hospice-based outpatient Multidisciplinary Breathlessness Support Service (MBSS) in Ireland. A sequential explanatory mixed methods design guided this study. People with chronic breathlessness participated in longitudinal questionnaires (n = 10), medical record audit (n = 14) and a post-discharge interview (n = 8). Caregivers (n = 1) and healthcare professionals involved in referral to (n = 2) and delivery of (n = 3) the MBSS participated in a cross-sectional interview. Quantitative and qualitative data were integrated deductively via the pillar integration process, guided by the RE-AIM framework. Integration of mixed methods data enhanced understanding of factors influencing the reach, adoption, implementation and maintenance of the MBSS, and the potential outcomes that were most meaningful for service users. Potential threats to the sustainability of the MBSS related to potential preconceptions of hospice care, the lack of standardized discharge pathways from the service and access to primary care services to sustain pharmacological interventions. This study suggests that an adapted multidisciplinary breathlessness support intervention is feasible and acceptable in a hospice context. However, to ensure optimal reach and maintenance of the intervention, activities are required to ensure that misconceptions about the setting do not influence willingness to accept referral to MBSS services and integration of services is needed to enable consistency in referral and discharge processes.

The impact of unpredictability of dyspnea offset on dyspnea perception, fear, and respiratory neural gating

Dyspnea is a debilitating and threatening symptom in various diseases. Affected patients often report the unpredictability of dyspnea episodes being particularly anxiety-provoking and amplifying the perception of dyspnea. Experimental studies testing dyspnea unpredictability together with related neural processes, physiological fear responses, and dyspnea-related personality traits are sparse. Therefore, we investigated the impact of unpredictability of dyspnea offset on dyspnea perception and fear ratings, respiratory neural gating and physiological fear indices, as well as the influence of interindividual differences in fear of suffocation (FoS). Forty healthy participants underwent a task manipulating the offset predictability of resistive load-induced dyspnea including one unloaded safety condition. Respiratory variables, self-reports of dyspnea intensity, dyspnea unpleasantness, and fear were recorded. Moreover, respiratory neural gating was measured in a paired inspiratory occlusion paradigm using electroencephalography, while electrodermal activity, startle eyeblink, and startle probe N100 were assessed as physiological fear indices. Participants reported higher dyspnea unpleasantness and fear when dyspnea offset was unpredictable compared to being predictable. Individuals with high levels of FoS showed the greatest increase in fear and overall higher levels of fear and physiological arousal across all conditions. Respiratory neural gating, startle eyeblink, and startle probe N100 showed general reductions during dyspnea conditions but no difference between unpredictable and predictable dyspnea conditions. Together, the current results suggest that the unpredictable offset of dyspnea amplifies dyspnea perception and fear, especially in individuals with high levels of FoS. These effects were unrelated to respiratory neural gating or physiological fear responses, requiring future studies on underlying mechanisms.

The Impact of Unpredictability on Dyspnea Perception, Anxiety and Interoceptive Error Processing

Dyspnea is a prevalent interoceptive sensation and the aversive cardinal symptom in many cardiorespiratory diseases as well as in mental disorders. Especially the unpredictability of the occurrence of dyspnea episodes has been suggested to be highly anxiety provoking for affected patients. Moreover, previous studies demonstrated that unpredictable exteroceptive stimuli increased self-reports and electrophysiological responses of anxiety such as the startle probe N100 as well as amplified the processing of errors as reflected by greater error-related negativity (ERN). However, studies directly examining the role of unpredictability on dyspnea perception, anxiety, and error processing are widely absent. Using high-density electroencephalography, the present study investigated whether unpredictable compared to predictable dyspnea would increase the perception of dyspnea, anxiety and interoceptive error processing. Thirty-two healthy participants performed a respiratory forced choice reaction time task to elicit an interoceptive ERN during two conditions: an unpredictable and a predictable resistive load-induced dyspnea condition. Predictability was manipulated by pairing (predictable condition) or not pairing (unpredictable condition) dyspnea with a startle tone probe. Self-reports of dyspnea and affective state as well as the startle probe N100 and interoceptive ERN were measured. The results demonstrated greater dyspnea unpleasantness in the unpredictable compared to the predictable condition. Post hoc analyses revealed that this was paralleled by greater anxiety, and greater amplitudes for the startle probe N100 and the interoceptive ERN during the unpredictable relative to the predictable condition, but only when the unpredictable condition was experienced in the first experimental block. Furthermore, higher trait-like anxiety sensitivity was associated with higher ratings for dyspnea unpleasantness and experimental state anxiety ratings. The present findings suggest that unpredictability increases the perception of dyspnea unpleasantness. This effect seems related to increased state and trait anxiety and interoceptive error processing, especially when upcoming dyspnea is particularly unpredictable, such as in early experimental phases. Future studies are required to further substantiate these findings in patients suffering from dyspnea.