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.

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.

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.

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.

Physiologic changes and clinical correlates of advanced dyspnea.

PURPOSE OF REVIEW: To discuss the pathophysiology of dyspnea as it relates to patients suffering with chronic respiratory illness or end-stage disease. RECENT FINDINGS: There are several publications highlighting important new concepts in this field including a new multidimensional model of dyspnea, similar to that developed for pain, that sheds new insight into the pathophysiology. Research in pulmonary rehabilitation, exercise testing and distractive auditory stimulation has also contributed to our understanding. Finally, there are new data on the emotional response of laboratory-induced dyspnea. SUMMARY: Dyspnea is a complex symptom widely prevalent in advanced disease that involves multiple causes and pathophysiologies. The sensation of dyspnea is subjective and often evokes discomfort, fear, and anxiety. We recommend that this symptom be evaluated whenever vital signs are taken.