Dyspnea relief: More than just the perception of a decrease in dyspnea
Introduction
Dyspnea is a multidimensional subjective experience of breathing discomfort encompassing sensory, affective and cognitive dimensions. Furthermore, dyspnea is mostly associated with physiological but also behavioural changes, including avoiding or adaptive strategies. As dyspnea is phylogenetically a very ancient sensation, it has presumably provided evolutionary advantages. Indeed, by its unpleasant nature, dyspnea acts as a preventative alarm signal, or at least to minimize harm to the integrity of the body by preserving it from asphyxia. Thereby, dyspnea has, like pain, potentially life-saving properties. The most popular illustration of this fact is that absent or impaired dyspnea perception may lead to severe or even life-threatening asthma exacerbation (Barnes, 1994). Most frequently however, rather than providing any advantage, dyspnea turns out to be a very distressful, and most predominant symptom in a large variety of different diseases and thereby a major cause of suffering. It follows that relief of dyspnea is a crucial concern in clinical practice, which in turn has generated an important number of clinical studies assessing the way of action, but predominantly, the outcome, in terms of decrease in dyspnea scores, of all the numerous different therapeutic interventions for dyspnea management. Much less work has been done on dyspnea relief as such i.e. a specific and highly complex construct. Indeed, like relief in general, dyspnea relief encompasses two different components, predominantly, the perception of offset of, or at least decrease in its underlying inherent unpleasant physical or mental stimulus, but also a positive valenced emotion i.e. pleasantness or euphoria and thus the perception of an hedonic switch from unpleasant to pleasant. Moreover, unlike for pain, and more recently for dyspnea, virtually nothing is currently known about central integration and more specifically, potential consequences of dyspnea relief on behaviour.
All these different aspects of relief will be addressed in the present paper. In the first part, after a brief overview and comments concerning current knowledge of the mechanisms of action of presently available and recognized therapeutic interventions for dyspnea, I shall consider relief in the larger framework of psychological models relative to human perception and emotion and current results from imaging studies. More specifically, I support the view, in the light of emerging results from specific albeit preliminary studies including personal work, that relief is a specific sensori-emotional experience, which basically is more complex than the mere perception of a decrease in dyspnea and that it involves characteristic neural substrates.
Section snippets
Dyspnea relief in the clinical context
In the first part of this section, I shall review the numerous and obvious reasons why dyspnea is a major concern, and its management an important challenge in clinical practice. In the second part, I present an integrative overview of the general mechanisms of action and impacts of current treatment strategies for dyspnea rather than to detail each of them. Indeed, both traditional and alternative interventions for dyspnea, especially regarding COPD, have been thoroughly addressed in several
General considerations about relief
Relief, basically the perception of offset of, or at least decrease in, noxious and/or unpleasant physical or mental stimuli, is a fundamental quite familiar subjective experience since it may be experienced in a large variety of different situations such as pain, moral or mental suffering, escape from danger or threat, thirst, hunger, heat or cold, and of course dyspnea. Regarding dyspnea, besides its predominant occurrence in the clinical context, relief can be easily experienced in normal
Concluding remarks
Much work remains to be done towards a more complete understanding of dyspnea relief, which given the burden of dyspnea, is before all, a major clinical concern. Yet, at the present state, new conceptual frameworks and recent, albeit preliminary results of current research suggest that dyspnea relief, despite its inherent and absolute dependence on preceding dyspnea (without dyspnea, no relief), encompasses specificity, both in terms sensori-emotional experience and neural substrates.
References (55)
- et al.
Cognitive and emotional influences in anterior cingulate cortex
Trends Cogn. Sci.
(2000) - et al.
The symptom burden of seriously ill hospitalized patients. SUPPORT Investigators. Study to understand prognoses and preferences for outcome and risks of treatment
J. Pain Symptom Manage.
(1999) The pathophysiology of hyperventilation disorders
Chest
(1996)- et al.
Ethnic differences: word descriptors used by African–American and white asthma patients during induced bronchoconstriction
Chest
(2000) - et al.
Postsurgical pain outcome assessment
Pain
(2002) The validity and reliability of pain measures in adults with cancer
J. Pain
(2003)- et al.
Effects of inhaled furosemide on CO(2) ventilatory responsiveness in humans
Pulm. Pharmacol. Ther.
(2002) - et al.
Temporal difference models and reward-related learning in the human brain
Neuron
(2003) - et al.
Complementary and alternative medicine in the management of pain, dyspnea, and nausea and vomiting near the end of life. A systematic review
J. Pain Symptom Manage.
(2000) - et al.
Verbal descriptors of dyspnea in patients with COPD at different intensity levels of dyspnea
Chest
(2007)
The language of breathlessness differentiates between patients with COPD and age-matched adults
Chest
PET activation study. Analgesia by electrostimulation of the trigeminal ganglion in patients with trigeminopathic pain: a PET activation study
Pain
Dyspnea: mechanisms, assessment, and management. A consensus statement
Am. J. Respir. Crit. Care Med.
The relationship between the visual analog pain intensity and pain relief scale changes during analgesic drug studies in chronic pain patients
Anesthesiology
Breathlessness in humans activates insular cortex
Neuroreport
Blunted perception and death from asthma
N. Engl. J. Med.
Imaging pain modulation in health and disease
Curr. Opin. Neurol.
Color vision in the comb frequency domain
Biol. Res.
Physiological role of pleasure
Science
Respiratory symptoms as predictors of 27 year mortality in a representative sample of British adults
Br. Med. J.
Coping and self-management strategies for dyspnea
Evidence for limbic system activation during CO2-stimulated breathing in man
J. Physiol.
A new view of pain as a homeostatic emotion
Trends Neurosci.
The language of breathlessness: use by patients of verbal descriptors
Am. Rev. Respir. Dis.
BOLD fMRI identifies limbic, paralimbic, and cerebellar activation during air hunger
J. Neurophysiol.
In vivo imaging of human limbic responses to nitrous oxide inhalation
Anesth. Analg.
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2015, Murray and Nadel's Textbook of Respiratory Medicine: Volume 1,2, Sixth EditionLung/chest expansion contributes to generation of pleasantness associated with dyspnoea relief
2012, Respiratory Physiology and NeurobiologyCitation Excerpt :These findings indicate that an increase in VT after removal of respiratory loading plays a crucial role in generation of ‘respiratory pleasure’ that is a specific sensory-emotional experience. As pointed out by the previous studies (Peiffer et al., 2008; Peiffer, 2009), a sudden decrease in dyspnoea observed immediately following the removal of respiratory loading is not necessarily synonymous with ‘respiratory pleasure’ since the decrease in dyspnoea and ‘respiratory pleasure’ may be different sensor experiences. Our finding that a considerable difference exists between time latencies of respiratory pleasure and dyspnoea decrease supports the concept that the dyspnoea decrease and the respiratory pleasure are two individual sensory experiences.
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