Rating Dyspnea and Pain: "No" is Not Always "Zero".

Nurses routinely assess pain in hospitalized patients; similar assessment of dyspnea is increasing. Most nurses start with a yes-no question when assessing pain or dyspnea; many record "no" as a zero rating, skipping the rating scale. We tested the hypothesis that recording "no" answers as "zero" fails to detect the symptoms that would have been detected with a rating scale. Nurses asked 60 patients yes-no questions about the presence of dyspnea and pain, then asked patients to rate the symptoms using a 0-10 scale. All "yes" answers were followed by a concordant rating (i.e., greater than zero). More than 25% of "no" answers were followed by a discordant rating (> zero). Documenting "no" as "zero" missed information potentially useful in care planning; patients who rate dyspnea above zero are at greater risk of adverse outcomes. This information can also provide opportunity to start a discussion with patients who may benefit from symptom management.

Association of dyspnoea, mortality and resource use in hospitalised patients.

As many as one in 10 patients experience dyspnoea at hospital admission but the relationship between dyspnoea and patient outcomes is unknown. We sought to determine whether dyspnoea on admission predicts outcomes.We conducted a retrospective cohort study in a single, academic medical centre. We analysed 67 362 consecutive hospital admissions with available data on dyspnoea, pain and outcomes. As part of the Initial Patient Assessment by nurses, patients rated "breathing discomfort" using a 0 to 10 scale (10="unbearable"). Patients reported dyspnoea at the time of admission and recalled dyspnoea experienced in the 24 h prior to admission. Outcomes included in-hospital mortality, 2-year mortality, length of stay, need for rapid response system activation, transfer to the intensive care unit, discharge to extended care, and 7- and 30-day all-cause readmission to the same institution.Patients who reported any dyspnoea were at an increased risk of death during that hospital stay; the greater the dyspnoea, the greater the risk of death (dyspnoea 0: 0.8% in-hospital mortality; dyspnoea 1-3: 2.5% in-hospital mortality; dyspnoea ≥4: 3.7% in-hospital mortality; p<0.001). After adjustment for patient comorbidities, demographics and severity of illness, increasing dyspnoea remained associated with inpatient mortality (dyspnoea 1-3: adjusted OR 2.1, 95% CI 1.7-2.6; dyspnoea ≥4: adjusted OR 3.1, 95% CI 2.4-3.9). Pain did not predict increased mortality. Patients reporting dyspnoea also used more hospital resources, were more likely to be readmitted and were at increased risk of death within 2 years (dyspnoea 1-3: adjusted hazard ratio 1.5, 95% CI 1.3-1.6; dyspnoea ≥4: adjusted hazard ratio 1.7, 95% CI 1.5-1.8).We found that dyspnoea of any rating was associated with an increased risk of death. Dyspnoea ratings can be rapidly collected by nursing staff, which may allow for better monitoring or interventions that could reduce mortality and morbidity.

Air Hunger: A Primal Sensation and a Primary Element of Dyspnea.

The sensation that develops as a long breath hold continues is what this article is about. We term this sensation of an urge to breathe "air hunger." Air hunger, a primal sensation, alerts us to a failure to meet an urgent homeostatic need maintaining gas exchange. Anxiety, frustration, and fear evoked by air hunger motivate behavioral actions to address the failure. The unpleasantness and emotional consequences of air hunger make it the most debilitating component of clinical dyspnea, a symptom associated with respiratory, cardiovascular, and metabolic diseases. In most clinical populations studied, air hunger is the predominant form of dyspnea (colloquially, shortness of breath). Most experimental subjects can reliably quantify air hunger using rating scales, that is, there is a consistent relationship between stimulus and rating. Stimuli that increase air hunger include hypercapnia, hypoxia, exercise, and acidosis; tidal expansion of the lungs reduces air hunger. Thus, the defining experimental paradigm to evoke air hunger is to elevate the drive to breathe while mechanically restricting ventilation. Functional brain imaging studies have shown that air hunger activates the insular cortex (an integration center for perceptions related to homeostasis, including pain, food hunger, and thirst), as well as limbic structures involved with anxiety and fear. Although much has been learned about air hunger in the past few decades, much remains to be discovered, such as an accepted method to quantify air hunger in nonhuman animals, fundamental questions about neural mechanisms, and adequate and safe methods to mitigate air hunger in clinical situations. © 2021 American Physiological Society. Compr Physiol 11:1449-1483, 2021.

Dyspnea, Acute Respiratory Failure, Psychological Trauma, and Post-ICU Mental Health: A Caution and a Call for Research.

Dyspnea is an uncomfortable sensation with the potential to cause psychological trauma. Patients presenting with acute respiratory failure, particularly when tidal volume is restricted during mechanical ventilation, may experience the most distressing form of dyspnea known as air hunger. Air hunger activates brain pathways known to be involved in posttraumatic stress disorder (PTSD), anxiety, and depression. These conditions are considered part of the post-intensive care syndrome. These sequelae may be even more prevalent among patients with ARDS. Low tidal volume, a mainstay of modern therapy for ARDS, is difficult to avoid and is likely to cause air hunger despite sedation. Adjunctive neuromuscular blockade does not prevent or relieve air hunger, but it does prevent the patient from communicating discomfort to caregivers. Consequently, paralysis may also contribute to the development of PTSD. Although research has identified post-ARDS PTSD as a cause for concern, and investigators have taken steps to quantify the burden of disease, there is little information to guide mechanical ventilation strategies designed to reduce its occurrence. We suggest such efforts will be more successful if they are directed at the known mechanisms of air hunger. Investigation of the antidyspnea effects of sedative and analgesic drugs commonly used in the ICU and their impact on post-ARDS PTSD symptoms is a logical next step. Although in practice we often accept negative consequences of life-saving therapies as unavoidable, we must understand the negative sequelae of our therapies and work to minimize them under our primary directive to "first, do no harm" to patients.

Silent hypoxaemia in COVID-19 patients.

The clinical presentation of COVID-19 due to infection with SARS-CoV-2 is highly variable with the majority of patients having mild symptoms while others develop severe respiratory failure. The reason for this variability is unclear but is in critical need of investigation. Some COVID-19 patients have been labelled with 'happy hypoxia', in which patient complaints of dyspnoea and observable signs of respiratory distress are reported to be absent. Based on ongoing debate, we highlight key respiratory and neurological components that could underlie variation in the presentation of silent hypoxaemia and define priorities for subsequent investigation.

'Scared to death' dyspnoea from the hospitalised patient's perspective.

Because dyspnoea is seldom experienced by healthy people, it can be hard for clinicians and researchers to comprehend the patient's experience. We collected patients' descriptions of dyspnoea in their own words during a parent study in which 156 hospitalised patients completed a quantitative multidimensional dyspnoea questionnaire. These volunteered comments describe the severity and wide range of experiences associated with dyspnoea and its impacts on a patients' life. They provide insights not conveyed by structured rating scales. We organised these comments into the most prominent themes, which included sensory experiences, emotional responses, self-blame and precipitating events. Patients often mentioned air hunger ('Not being able to get air is the worst thing that could ever happen to you.'), anxiety, and fear ('Scared. I thought the world was going to end, like in a box.'). Their value in patient care is suggested by one subject's comment: 'They should have doctors experience these symptoms, especially dyspnoea, so they understand what patients are going through.' Patients' own words can help to bridge this gap of understanding.

Intensive Care Nurses' Perceptions of Routine Dyspnea Assessment.

BACKGROUND: Dyspnea (breathing discomfort) is commonly experienced by critically ill patients and at this time is not routinely assessed and documented. Intensive care unit nurses at the study institution recently instituted routine assessment and documentation of dyspnea in all patients able to report using a numeric scale ranging from 0 to 10. OBJECTIVE: To assess nurses' perceptions of the utility of routine dyspnea measurement, patients' comprehension of assessment questions, and the impact on nursing practice and to gather nurses' suggestions for improvement. METHODS: Data were obtained from interviews with intensive care unit nurses in small focus groups and an anonymous online survey randomly distributed to nurses representing all intensive care units. RESULTS: Intensive care unit nurses affirmed the importance of routine dyspnea assessment and documentation. Before implementing the measurement tool, nurses often assessed for breathing discomfort in patients by using observed signs. Most nurses agreed that routine assessment can be used to predict patients' outcomes and improve patient-centered care. Nurses found the assessment tool easy to use and reported that it did not interfere with workflow. Nurses felt that patients were able to provide meaningful ratings of dyspnea, similar to ratings of pain, and often used patients' ratings in conjunction with observed physical signs to optimize patient care. CONCLUSION: Our study shows that nurses understand the importance of routine dyspnea assessment and that the addition of a simple patient report scale can improve care delivery and does not add to the burden of work-flow.

Controlled Delivery of 80 mg Aerosol Furosemide Does Not Achieve Consistent Dyspnea Relief in Patients.

PURPOSE: Aerosol furosemide may be an option to treat refractory dyspnea, though doses, methods of delivery, and outcomes have been variable. We hypothesized that controlled delivery of high dose aerosol furosemide would reduce variability of dyspnea relief in patients with underlying pulmonary disease. METHODS: Seventeen patients with chronic exertional dyspnea were recruited. Patients rated recently recalled breathing discomfort on a numerical rating scale (NRS) and the multidimensional dyspnea profile (MDP). They then performed graded exercise using an arm-ergometer. The NRS was completed following each exercise grade, and the MDP was repeated after a pre-defined dyspnea threshold was reached. During separate visits, patients received either aerosol saline or 80 mg of aerosol furosemide in a randomized, double-blind, crossover design. After treatment, graded exercise to the pre-treatment level was repeated, followed by completion of the NRS and MDP. Treatment effect was defined as the difference between pre- and post-treatment NRS at end exercise, expressed in absolute terms as % Full Scale. "Responders" were defined as those showing treatment effect ≥ 20% of full scale. RESULTS: Final analysis included 15 patients. Neither treatment produced a statistically significant change in NRS and there was no significant difference between treatments (p = 0.45). There were four "responders" and one patient whose dyspnea worsened with furosemide; two patients were responders with saline, of whom one also responded to furosemide. No adverse events were reported. CONCLUSIONS: High dose controlled delivery aerosol furosemide was not statistically different from saline placebo at reducing exercise-induced dyspnea. However, a clinically meaningful improvement was noted in some patients.

A Multidimensional Profile of Dyspnea in Hospitalized Patients.

BACKGROUND: Dyspnea is prevalent among hospitalized patients but little is known about the experience of dyspnea among inpatients. We sought to characterize the multiple sensations and associated emotions of dyspnea in patients admitted with dyspnea to a tertiary care hospital. METHODS: We selected patients who reported breathing discomfort of at least 4/10 on admission (10 = unbearable). Research staff recruited 156 patients within 24 hours of admission and evaluated daily patients' current and worst dyspnea with the Multidimensional Dyspnea Profile; patients participated in the study 2.6 days on average. The Multidimensional Dyspnea Profile assesses overall breathing discomfort (A1), intensity of five sensory qualities of dyspnea, and 5 negative emotional responses to dyspnea. Patients were also asked to rate whether current levels of dyspnea were "acceptable." RESULTS: At the time of the first research interview, patients reported slight to moderate dyspnea (A1 median 4); however, most patients reported experiencing severe dyspnea in the 24 hours before the interview (A1 mean 7.8). A total of 54% of patients with dyspnea ≥4 on day 1 found the symptom unacceptable. The worst dyspnea each day in the prior 24 hours usually occurred at rest. Dyspnea declined but persisted through hospitalization for most patients. "Air hunger" was the dominant sensation, especially when dyspnea was strong (>4). Anxiety and frustration were the dominant emotions associated with dyspnea. CONCLUSIONS: This first multidimensional portrait of dyspnea in a general inpatient population characterizes the sensations and emotions dyspneic patients endure. The finding that air hunger is the dominant sensation of severe dyspnea has implications for design of laboratory models of these sensations and may have implications for targets of palliation of symptoms.

Prevalence of Dyspnea Among Hospitalized Patients at the Time of Admission.

CONTEXT: Dyspnea is an uncomfortable and distressing sensation experienced by hospitalized patients. OBJECTIVES: There is no large-scale study of the prevalence and intensity of patient-reported dyspnea at the time of admission to the hospital. METHODS: Between March 2014 and September 2016, we conducted a prospective cohort study among all consecutive hospitalized patients at a single tertiary care center in Boston, MA. During the first 12 hours of admission to medical-surgical and obstetric units, nurses at our institution routinely collect a patient's 1) current level of dyspnea on a 0-10 scale with 10 anchored at "unbearable," 2) worst dyspnea in the past 24 hours before arrival at the hospital on the same 0-10 scale, and 3) activities that were associated with dyspnea before admission. The prevalence of dyspnea was identified, and tests of difference were performed across patient characteristics. RESULTS: We analyzed 67,362 patients, 12% of whom were obstetric patients. Fifty percent of patients were admitted to a medical-surgical unit after treatment in the emergency department. Among all noncritically ill inpatients, 16% of patients experienced dyspnea in the 24 hours before the admission. Twenty-three percent of patients admitted through the emergency department reported any dyspnea in the past 24 hours. Eleven percent experienced some current dyspnea when interviewed within 12 hours of admission with 4% of patients experiencing dyspnea that was rated 4 or greater. Dyspnea of 4 or more was present in 43% of patients admitted with respiratory diagnoses and 25% of patients with cardiovascular diagnoses. After multivariable adjustment for severity of illness and patient comorbidities, patients admitted on the weekend or during the overnight nursing shift were more likely to report dyspnea on admission. CONCLUSION: Dyspnea is a common symptom among all hospitalized patients. Routine documentation of dyspnea is feasible in a large tertiary care center.

Aerosol furosemide for dyspnea: High-dose controlled delivery does not improve effectiveness.

Published studies have shown great variability in response when aerosolized furosemide has been tested as a palliative treatment for dyspnea. We hypothesized that a higher furosemide dose with controlled aerosol administration would produce consistent dyspnea relief. We optimized deposition by controlling inspiratory flow (300-500mL/s) and tidal volume (15% predicted vital capacity) while delivering 3.4µm aerosol from either saline or 80mg of furosemide. We induced dyspnea in healthy subjects by varying inspired PCO2 while restricting minute ventilation. Subjects rated "Breathing Discomfort" on a Visual Analog Scale (BDVAS, 100% Full Scale≡intolerable). At the PETCO2 producing 60% BDVAS pre-treatment, furosemide produced a clinically meaningful reduction of BDVAS (i.e., >20% FS) in 5/11 subjects; saline reduced dyspnea in 3/11 subjects; neither treatment worsened dyspnea in any subject. Furosemide and saline treatment effects were not statistically different. There were no significant adverse events. Higher furosemide dose and controlled delivery did not improve consistency of treatment effect compared with prior studies.

Aerosol furosemide for dyspnea: Controlled delivery does not improve effectiveness.

Aerosolized furosemide has been shown to relieve dyspnea; nevertheless, all published studies have shown great variability in response. This dyspnea relief is thought to result from the stimulation of slowly adapting pulmonary stretch receptors simulating larger tidal volume. We hypothesized that better control over aerosol administration would produce more consistent dyspnea relief; we used a clinical ventilator to control inspiratory flow and tidal volume. Twelve healthy volunteers inhaled furosemide (40mg) or placebo in a double blind, randomized, crossover study. Breathing Discomfort was induced by hypercapnia during constrained ventilation before and after treatment. Both treatments reduced breathing discomfort by 20% full scale. Effectiveness of aerosol furosemide treatment was weakly correlated with larger tidal volume. Response to inhaled furosemide was inversely correlated to furosemide blood level, suggesting that variation among subjects in the fate of deposited drug may determine effectiveness. We conclude that control of aerosol delivery conditions does not improve consistency of treatment effect; we cannot, however, rule out placebo effect.

Routine dyspnea assessment and documentation: Nurses' experience yields wide acceptance.

BACKGROUND: Dyspnea (breathing discomfort) is a common and distressing symptom. Routine assessment and documentation can improve management and relieve suffering. A major barrier to routine dyspnea documentation is the concern that it will have a deleterious effect on nursing workflow and that it will not be readily accepted by nurses. Nurses at our institution recently began to assess and document dyspnea on all medical-surgical patients upon admission and once per shift throughout their hospitalization. A year after dyspnea measurement was implemented we explored nurses' approach to dyspnea assessment, their perception of patient response, and their perception of the utility and burden of dyspnea measurement. METHODS: We obtained feedback from nurses using a three-part assessment of practice: 1) a series of recorded focus group interviews with nurses, 2) a time-motion observation of nurses performing routine dyspnea and pain assessment, and 3) a randomized, anonymous on-line survey based, in part, on issues raised in focus groups. RESULTS: Ninety-four percent of the nurses surveyed reported administering the dyspnea assessment is "easy" or "very easy". None of the nurses reported that assessing dyspnea negatively impacted workflow and many reported that it positively improved their practice by increasing their awareness. Our time-motion data showed dyspnea assessment and documentation takes well less than a minute. Nurses endorsed the importance of routine measurement and agreed that most patients were able to provide a meaningful rating of their dyspnea. Nurses found the patient report very useful, and used it in conjunction with observed signs to respond to changes in a patient's condition. CONCLUSIONS: In this study, we have demonstrated that routine dyspnea assessment and documentation was widely accepted by the nurses at our institution. Our nurses fully incorporated routine dyspnea assessment and documentation into their practice and felt that it improved patient-centered care.

The Effect of Aerosol Saline on Laboratory-Induced Dyspnea.

PURPOSE: In the 'placebo arm' of a recent study, we found that aerosol saline (sham treatment) produced substantial relief of laboratory-induced dyspnea (Breathing discomfort-BD) in nearly half the subjects. The sham intervention included a physiological change, and instructions to subjects could have produced expectation of dyspnea relief. In the present study, we attempted to discover whether the response to sham aerosol was driven by behavioral or physiological aspects of the intervention. METHODS: Dyspnea (air hunger) was evoked by constraining tidal volume during graded hypercapnia. We measured [Formula: see text] versus BD relationship before and after aerosol saline. To minimize subjects' expectations of dyspnea relief, participants were clearly instructed that we would only deliver saline aerosol. In Protocol 1, we delivered aerosol saline with a ventilator (mimicking our prior study); in Protocol 2, we delivered aerosol without a ventilator. RESULTS: Administration of aerosol saline had little effect on BD in this group of subjects with one exception: one subject experienced appreciable reduction in BD in Protocol 1. This treatment effect was less in Protocol 2. The two most likely explanations are (a) that procedures surrounding ventilator administration of aerosol produced a psychological placebo treatment effect even though the subject knew a drug was not given; (b) there were behavioral changes in breathing undetected by our measurements of respiratory flow and volume that altered the subjects comfort. CONCLUSION: When the expectation of treatment effect is minimized, a significant reduction in dyspnea in response to saline placebo is uncommon but not impossible.

Prevalence and Predictive Value of Dyspnea Ratings in Hospitalized Patients: Pilot Studies.

BACKGROUND: Dyspnea (breathing discomfort) can be as powerfully aversive as pain, yet is not routinely assessed and documented in the clinical environment. Routine identification and documentation of dyspnea is the first step to improved symptom management and it may also identify patients at risk of negative clinical outcomes. OBJECTIVE: To estimate the prevalence of dyspnea and of dyspnea-associated risk among hospitalized patients. DESIGN: Two pilot prospective cohort studies. SETTING: Single academic medical center. PATIENTS: Consecutive patients admitted to four inpatient units: cardiology, hematology/oncology, medicine, and bariatric surgery. MEASUREMENTS: In Study 1, nurses documented current and recent patient-reported dyspnea at the time of the Initial Patient Assessment in 581 inpatients. In Study 2, nurses documented current dyspnea at least once every nursing shift in 367 patients. We describe the prevalence of burdensome dyspnea, and compare it to pain. We also compared dyspnea ratings with a composite of adverse outcomes: 1) receipt of care from the hospital's rapid response system, 2) transfer to the intensive care unit, or 3) death in hospital. We defined burdensome dyspnea as a rating of 4 or more on a 10-point scale. RESULTS: Prevalence of burdensome current dyspnea upon admission (Study 1) was 13% (77 of 581, 95% CI 11%-16%). Prevalence of burdensome dyspnea at some time during the hospitalization (Study 2) was 16% (57 of 367, 95% CI 12%-20%). Dyspnea was associated with higher odds of a negative outcome. CONCLUSIONS: In two pilot studies, we identified a significant symptom burden of dyspnea in hospitalized patients. Patients reporting dyspnea may benefit from a more careful focus on symptom management and may represent a population at greater risk for negative outcomes.